# Modeled Attainment Test Software

April 2014 Prepared for Office of Air Quality Planning and Standards U.S. Environmental Protection Agency Research Triangle Park, NC Brian Timin, Project Manager Prepared by Abt Associates Inc. 

# User's Manual Abt Associates Inc. 4550 Montgomery Avenue Bethesda, MD 20814 www.abtassociates.comAbt Associates Inc. April 2014 2 

# Table of Contents

Chapter 1 Welcome to MATS, the Modeled Attainment Test Software 9

10 1.1 How to Use this Manual 11 1.2 Computer Requirements 11 1.3 Installing MATS 14 1.4 Installing an Updated Version of MATS 14 1.5 Uninstalling MATS 15 1.6 Contact for Comments and Questions


## Chapter 2 Terminology & File Types 16

16 2.1 Common Terms 17 ASR File 2.1.1 17 BMP File 2.1.2 17 Class I Area 2.1.3 17 Configuration File 2.1.4 18 CSV File 2.1.5 18 Deciviews 2.1.6 18 Design Value 2.1.7 19 Domain 2.1.8 19 Extinction 2.1.9 19 FRM Monitors 2.1.10 19 Gradient Adjustment 2.1.11 19 IMPROVE Monitors 2.1.12 19 Interpolation 2.1.13 20 Inverse Distance Weights 2.1.14 21 Log File 2.1.15 22 Output Navigator 2.1.16 22 Output File 2.1.17 22 Point Estimate 2.1.18 22 RRF 2.1.19 22 SANDWICH 2.1.20 22 Scenario Name 2.1.21 23 SMAT 2.1.22 23 Spatial Field 2.1.23 24 Spatial Gradient 2.1.24 24 STN Monitors 2.1.25 24 Temporal Adjustment 2.1.26 24 VNA 2.1.27 24 VNA - Detailed Description 28 2.2 File TypesContents

Abt Associates Inc. April 2014 3 

## Chapter 3 Overview of MATS Components 29

29 3.1 Start 30 Annual PM Analysis 3.1.1 36 Daily PM Analysis 3.1.2 43 Ozone Analysis 3.1.3 48 Visibility Analysis 3.1.4 52 3.2 Output Navigator 54 3.3 Map View 54 3.4 Help


## Chapter 4 Annual PM Analysis: Quick Start Tutorial 56

56 4.1 Step 1. Start MATS 57 4.2 Step 2. Output Choice 59 4.3 Step 3. Output Choice - Advanced 60 4.4 Step 4. Data Input 61 4.5 Step 5. Species Fractions Calculation Options 63 4.6 Step 6. Species Fractions Calculation Options - Advanced 64 4.7 Step 7. PM2.5 Calculation Options 65 4.8 Step 8. Model Data Options 66 4.9 Step 9. Final Check 70 4.10 Step 10. Map Output 78 4.11 Step 11. View Output


## Chapter 5 Annual PM Analysis: Details 82

83 5.1 Output Choice 84 Scenario Name 5.1.1 86 Standard Analysis 5.1.2 86 Step 1: Baseline Quartelry Average PM2.5 Calculation 87 Step 2: Baseline Quarterly Average Species Calculation 94 Step 3: Forecasted Quarterly Average Species Calculation 96 Step 4: Forecasted Design Value Calculation 97 Output Description 98 Quarterly Model Data 5.1.3 100 Species Fractions 5.1.4 100 Species Fractions Calculation 101 Output Description 102 5.2 Output Choice - Advanced 104 Spatial Field Estimates 5.2.1 104 Gradient-Adjustment- ("Fused fields")Abt Associates Inc. April 2014 4 106 Output Description - Interpolate FRM & Speciation Monitor Data to Spatial Field
108 Output Description - Interpolate Gradient-Adjusted FRM & Speciation Monitor Data to Spatial Field 109 Miscellaneous Output 5.2.2 109 Quarterly Average Files 113 Output Description - High County Sites 113 Species Fractions Spatial Field 115 Output Description - Quarterly Average Speciated Monitors 116 Design Value Periods 116 Neighbor Files 118 5.3 Data Input 120 Species Data Input 5.3.1 122 PM2.5 Monitor Data Input 5.3.2 122 Unofficial Daily PM2.5 Monitor Data Input 124 Official Quarterly PM2.5 Monitor Data Input 125 Model Data Input 5.3.3 126 5.4 Species Fractions Calculation Options 127 Monitor Data Years 5.4.1 128 Delete Specifed Data Values 5.4.2 129 Minimum Data Requirements 5.4.3 131 5.5 Species Fractions Calculation Options - Advanced 131 Interpolation Options for Species Fractions Calculation 5.5.1 133 Miscellaneous Options 5.5.2 133 Internal Precision of the Calculations 5.5.3 134 5.6 PM2.5 Calculation Options 135 PM2.5 Monitor Data Years 5.6.1 135 Design Values 5.6.2 136 Completion Code Use 137 Valid FRM Monitors 5.6.3 137 NH4 Future Calculation 5.6.4 137 5.7 Model Data Options 138 5.8 Final Check


## Chapter 6 Daily PM Analysis: Quick Start Tutorial 140

140 6.1 Step 1. Start MATS 141 6.2 Step 2. Output Choice 143 6.3 Step 3. Output Choice - Advanced 143 6.4 Step 4. Data Input 144 6.5 Step 5. Species Fractions Calculation Options 146 6.6 Step 6. Species Fractions Calculation Options - Advanced 148 6.7 Step 7. PM2.5 Calculation Options 148 6.8 Step 8. Model Data Options 149 6.9 Step 9. Final Check 153 6.10 Step 10. Map Output 159 6.11 Step 11. View OutputContents

Abt Associates Inc. April 2014 5 

## Chapter 7 Daily PM Analysis: Details 162

162 7.1 Output Choice 164 Scenario Name 7.1.1 165 Standard Analysis 7.1.2 166 Step 1: Baseline Top 32 Ranked PM2.5 Calculation 166 Step 2: Baseline Top 32 Ranked Species Calculation 174 Step 3: Calculate Relative Response Factors 174 Step 4: Forecasted Peak Species Calculation 177 Step 5: Forecasted Design Value Calculation 180 Output Description 181 Quarterly Peak Model Data 7.1.3 182 Species Fractions 7.1.4 183 Species Fractions Calculation 183 Output Description 184 7.2 Output Choice - Advanced 185 Miscellaneous Outputs 7.2.1 186 Daily Files 189 Output Description - High County Sites 190 Design Value Periods 190 Output Description - Quarterly Average Speciated Monitors 191 Neighbor Files 192 7.3 Data Input 194 Species Data Input 7.3.1 196 PM2.5 Monitor Data Input 7.3.2 196 Unofficial Daily PM2.5 Monitor Data Input 198 Official Daily PM2.5 Monitor Data Input 199 Model Data Input 7.3.3 201 7.4 Species Fractions Calculation Options 202 Monitor Data Years 7.4.1 203 Delete Specifed Data Values 7.4.2 203 Minimum Data Requirements 7.4.3 205 7.5 Species Fractions Calculation Options - Advanced 206 Using Monitor Data to Calculate Species Fractions 7.5.1 209 Interpolation Options for Species Fractions Calculation 7.5.2 210 Miscellaneous Options 7.5.3 211 Internal Precision of the Calculations 7.5.4 211 7.6 PM2.5 Calculation Options 212 PM2.5 Monitor Data Years 7.6.1 212 Valid FRM Monitors 7.6.2 213 NH4 Future Calculation 7.6.3 213 7.7 Model Data Options 214 7.8 Final Check


## Chapter 8 Ozone Analysis: Quick Start Tutorial 216

216 8.1 Step 1. Start MATSAbt Associates Inc. April 2014 6 217 8.2 Step 3. Data Input 219 8.3 Step 2. Output Choice 220 8.4 Step 4. Filtering and Interpolation 221 8.5 Step 5. RRF & Spatial Gradient 222 8.6 Step 6. Final Check 224 8.7 Step 7. Load & Map Output 231 8.8 Step 8. View & Export Output


## Chapter 9 Ozone Analysis: Details 236

236 9.1 Choose Desired Output 237 Scenario Name 9.1.1 239 Point Estimates 9.1.2 239 Baseline Ozone 239 Temporally-Adjust Baseline Ozone 240 Spatial Field 9.1.3 241 Baseline - interpolate monitor data to spatial field 242 Baseline - interpolate gradient-adjusted monitor data to spatial field

242 Forecast - interpolate monitor data to spatial field. Temporally-adjust ozone levels
243 Forecast - interpolate gradient-adjusted monitor data to spatial field. Temporally-adjust ozone levels 243 Design Value Periods 9.1.4 244 Ozone Output Variable Description 9.1.5 244 Ozone Monitors -- monitor data, temporally adjusted 2015.csv

245 Ozone Monitors -- county high monitoring sites, temporally adjusted 2015.csv
245 Spatial Field -- interpolated monitor data, temporally adjusted; gradient-adjusted monitor data, temporally adjusted 2015.csv 246 9.2 Data Input 247 Monitor Data 9.2.1 248 Model Data 9.2.2 249 EPA Default Model Data 249 Using Model Data 9.2.3 251 Nearby Monitor Calculation - Example 1 253 9.3 Filtering and Interpolation 253 Choose Ozone Design Values 9.3.1 254 Valid Ozone Monitors 9.3.2 254 Minimum Number Design Values 255 Required Design Values 255 Default Interpolation Method 9.3.3 256 9.4 RRF and Spatial Gradient 257 RRF Setup 9.4.1 259 RRF Calculation - Example 1 260 RRF Calculation - Example 2 263 RRF Calculation - Example 3 266 RRF Calculation - Example 4 267 RRF Calculation - Example 5 269 RRF Calculation Spatial Gradient with Backstop Threshold - Example 6 272 Spatial Gradient Setup 9.4.2Contents

Abt Associates Inc. April 2014 7 273 Spatial Gradient Calculation - Example 1 275 Spatial Gradient Calculation - Example 2 277 Spatial Gradient Calculation - Example 3 279 9.5 Final Check 280 Running MATS in Batch Mode 9.5.1


## Chapter 10 Visibility Analysis: Quick Start Tutorial 281

281 10.1 Step 1. Start MATS 282 10.2 Step 2. Output Choice 284 10.3 Step 3. Data Input 285 10.4 Step 4. Filtering 286 10.5 Step 5. Final_Check 289 10.6 Step 6. Load and Map Results 298 10.7 Step 7. Working with Configuration File


## Chapter 11 Visibility Analysis: Details 304

304 11.1 Choose Desired Output 305 Scenario Name 11.1.1 307 Forecast Visibility at Class I Areas 11.1.2 309 Old IMPROVE Equation 310 New IMPROVE Equation 312 Choose Model Grid Cell 312 Visibility Output Variable Description 11.1.3 313 Forecasted Visibility Data.csv 314 Forecasted Visibility - all design values.csv 315 Class 1 Area and IMPROVE Monitor Identifiers and Locations.csv 316 Used Model Grid Cells - Base/Future Data.csv 316 11.2 Data Input 317 Monitor Data Input 11.2.1 318 Monitor Data Description (Old Equation) 319 Monitor Data Description (New Equation) 321 Linkage between Monitors & Class I Areas 322 Model Data Input 11.2.2 324 Using Model Data for Temporal Adjustment 329 11.3 Filtering 330 Example Valid Visibility Monitors 11.3.1 332 11.4 Final Check 334 Running MATS in Batch Mode 11.4.1


## Chapter 12 Output Navigator 335

338 12.1 Add Output Files to Map 340 12.2 View FilesAbt Associates Inc. April 2014 8 340 Configuration File 12.2.1 342 Log File 12.2.2 343 Output Files 12.2.3 347 12.3 Extract Files


## Chapter 13 Map View 350

350 13.1 Loading Variables 352 Loading with Taskbar 13.1.1 355 13.2 Plotting a Value 358 Plotting Options 13.2.1 362 13.3 Zoom Options & Pan View 364 13.4 Standard Layers 365 13.5 Exporting Maps & Data Files 367 Exporting CSV Data File 13.5.1


## Chapter 14 Frequently Asked Questions 369

369 14.1 Where is there a description of output variables? 369 14.2 Removing Data


## Chapter 15 References 371Welcome to MATS, the Modeled Attainment Test Software

April 2014 Abt Associates Inc. 9 

## 1 

# Welcome to MATS, the Modeled Attainment Test Software 1

The Modeled Attainment Test Software (MATS) is primarily intended as a tool to implement the modeled attainment tests for particulate matter (PM 2.5 

### ) and ozone (O 3 

### ), and to perform the uniform rate of progress analysis for regional haze (visibility). Detailed information on the attainment tests can be found in U.S. EPA's modeling guidance, "Guidance on the Use of Models and Other Analyses for Demonstrating Attainment of the Air Quality Goals for Ozone, PM 2.5 

### , and Regional Haze." The modeling guidance can be found at http://www.epa.gov/ttn/scram/guidance_sip.htm

. This Chapter provides a brief description of how to use this manual, computer requirements, steps to install and uninstall MATS, and contact information for comments and questions: How to Use this Manual Computer Requirements Installing MATS Uninstalling MATS Contact for Comments and Questions

.Welcome to MATS, the Modeled Attainment Test Software

April 2014 Abt Associates Inc. 10 

## 1.1 How to Use this Manual This manual provides step-by-step instructions on how to use MATS. New users should start with the Overview of MATS Components chapter, which is very short, but provides a good overview of the model and how it works. You can then use tutorial chapters to get started using the model. There are separate tutorials for Annual and DailyParticulate Matter (PM), Ozone , and Visibility . In addition to these relatively simple tutorials, you can go on to learn more on each subject in the chapters on Annual PM Analysis: Details , Daily PM Analysis: Details , Ozone Analysis: Details , and Visibility Analysis: Details . Use the rest of the manual to answer any specific questions you may have. There is a chapter on the Output Navigator , which is the starting point for examining your results. The Map Viewchapter details how to map results. Finally, the Frequently Asked Questionschapter reviews and answers some of the common questions that arise when using MATS. In sections that provide instructions on navigating the model, the following conventions are observed: menu items, buttons, and tab and selection box labels are in bold type; prompts and messages are enclosed in quotation marks; and drop-down menu items, options to click or check, and items that need to be filled in or selected by the user are italicized. Common terms are defined in the Terminology and File Types chapter. The Referencesection provides citations for documents relevant to MATS.Welcome to MATS, the Modeled Attainment Test Software

April 2014 Abt Associates Inc. 11 

## 1.2 Computer Requirements MATS requires a Windows platform, and can be used on machines running Windows2000, as well as more recent versions of Windows. In particular, MATS requires a computer with:

· Windows 2000 or greater.

· 512 megabytes of RAM or greater.

· Intel® or compatible processor, Pentium 166 MHz or higher. 1 GHz processor or greater recommended for optimum performance

.

· A CD-ROM drive for CD based installation. Alternatively, a high speed internet connection can be used to download the installer. The installer package can be found at:

· At least 3 GB free space recommended. 

## 1.3 Installing MATS Load the installation file (MATS_Setup.exe) onto your hard drive. Double-click the file. This will initiate the installation process, which takes about five to ten minutes, depending on the speed of your computer.Welcome to MATS, the Modeled Attainment Test Software

April 2014 Abt Associates Inc. 12 

### Click the Nextbutton. This will bring up the MATS - InstallShield Wizard

.Welcome to MATS, the Modeled Attainment Test Software

April 2014 Abt Associates Inc. 13 

### Click the Installbutton. After the installation of MATS, a final window will appear to complete the process.Welcome to MATS, the Modeled Attainment Test Software

April 2014 Abt Associates Inc. 14 

### Click the Finishbutton. Note that some problems have occurred in the past, when trying to install MATS from a network drive. If this problem occurs, move the MATS_Setup.exe file to your local hard drive. 

## 1.4 Installing an Updated Version of MATS If a previous version of MATS is already installed on your computer, you will need to uninstall the old version using the Windows Control Panel prior to installing the new version (see next section). Note that uninstalling MATS will notdelete your MATS output files. 

## 1.5 Uninstalling MATS To uninstall MATS, go to Control Panel, Add/Remove Programs and highlight MATS.Welcome to MATS, the Modeled Attainment Test Software

April 2014 Abt Associates Inc. 15 

### Click the Remove button. This will bring up a window asking you to confirm the removal.

Note that removing the software will not remove the files that you have generated with MATS. For example, the Output folder will remain with any files ( e.g. , *.ASR files) that you have created. 

## 1.6 Contact for Comments and Questions For comments and questions, please contact Brian Timin at the United States Environmental Protection Agency. Address: C339-01, USEPA Mailroom, Research Triangle Park, NC 27711 Email: timin.brian@epa.gov Telephone: 919-541-1850.Terminology & File Types

April 2014 Abt Associates Inc. 16 

## 2 

# Terminology & File Types 2
The first section of this chapter explains Common Terms used in this user ’ s manual and in the model, and references, where possible, other sections in this manual to find more detailed information. The second section describes the File Types used in MATS. 

## 2.1 Common Terms The following include terms commonly used in MATS: ASR File BMP File Class I Area Configuration File CSV File Deciviews Design Value Domain FRM Monitors Gradient Adjustment IMPROVE Monitors Interpolation Inverse Distance Weights Log File Output Navigator Output File Point Estimate RRF SANDWICH Scenario Name SMAT Spatial FieldTerminology & File Types

April 2014 Abt Associates Inc. 17 

### Spatial Gradient STN Monitors Temporal Adjustment VNA


## 2.1.1 ASR File An ASR File contains three types of results from a MATS run: Log File , Configuration File , and Output Files . The extension .ASR is used after the Scenario Name . The data in an .ASR file can viewed and extracted using the O utput Navigator

. 

## 2.1.2 BMP File BMP is a standard file format for computers running the Windows operating system. The format was developed by Microsoft for storing bitmap files in a device-independent bitmap (DIB) format that will allow Windows to display the bitmap on any type of display device. The term "device independent" means that the bitmap specifies pixel color in a form independent of the method used by a display to represent color. *

* See : http://www.prepressure.com/formats/bmp/fileformat.htm

. 

## 2.1.3 Class I Area A Class I Area is defined by the Clean Air Act to include national parks greater than 6,000 acres, wilderness areas and national memorial parks greater than 5,000 acres, and international parks that existed as of August 1977. * The Regional Haze rule requires visibility improvements in 156 specific Class I areas. The MATS visibility analysis will calculate visibility values for these areas.

* See : http://views.cira.colostate.edu/web/Glossary.aspx 

## 2.1.4 Configuration File A Configuration File stores the choices that you have made when using MATS. A useful feature of a Configuration File is that it is reusable. You can use an existing Configuration File, make some minor changes to generate a new set of results, without having to explicitly set each of the choices you made in the previous Configuration. The section on the Output Navigatorprovides additional details on accessing and viewing a Configuration File.Terminology & File Types

April 2014 Abt Associates Inc. 18 

## 2.1.5 CSV File A comma separated values (CSV) file (*.csv) can be read using a text editor, or by various spreadsheet and database programs, such as Microsoft Excel. Note: Detailed formatting in .csv files such as leading zeroes and "" cannot be seen in Excel. To see formatting of MATS input files, open .csv files with a text editor, such as WordPad.



## 2.1.6 Deciviews The deciview index is a measure of visibility. EPA selected the deciview index as the standard metric for tracking progress in EPA's regional haze program, largely because it provides a linear scale for perceived visual changes over a wide range of conditions. On a particle-free, pristine day, the deciview index has a value of zero (Slant Visual Range (SVR)=391 km). On a relatively clear day in the Great Smoky Mountains the deciview index might be about 16 (SVR=79 km) and on a relatively hazy day the deciview index might be about 31 (SVR=201 km). For each 10 percent increase in light-extinction, the deciview index goes up by one. So, higher deciview values mean worse visibility. Under many scenic conditions, a change of one deciview is considered to be just perceptible by the average person.


## 2.1.7 Design Value The design value is the monitored reading used by EPA to determine an area's air qualityTerminology & File Types

April 2014 Abt Associates Inc. 19 

### status; e.g., for ozone, the 3 year average of the annual fourth highest reading measured at each monitor is the design value. Ozone design values are calculated in accordance with 40 CFR Part 50.10, and Appendix I to Part 50. The calculation of annual and 24-hour average PM 2.5 

### design values can be found in 40 CFR Part 50, Appendix N.


## 2.1.8 Domain A Domain (or Model Domain) refersto the coverage of an air quality model, or the area of the country for which there are model values. MATS calculates design values and/or spatial fieldsfor an area encompassed by the coordinates given within a MATS input file.


## 2.1.9 Extinction Light extinction is the sum of the light scattering and light absorption by particles and gases in the atmosphere, and is measured in inverse megameters (Mm-1), relating how much light is extinguished per megameter. Higher extinction values mean worse visibility.


## 2.1.10 FRM Monitors Federal Reference Method (FRM) monitors used to determine attainment or nonattainment.The term "FRM" is frequently used to describe the network of PM 2.5 

### mass monitors.


## 2.1.11 Gradient Adjustment A gradient adjustment is used to scale, or adjust, monitor data when using monitor data to estimate air pollution levels in unmonitored areas. It is calculated as the ratio of the model value in the unmonitored area to the value in the monitored area. In MATS, gradient adjustments can be used for PM Analyses (daily or annual) and Ozone Analyses

. 

## 2.1.12 IMPROVE Monitors Interagency Monitoring of PROtected Visual Environments (IMPROVE) is a collaborative monitoring program established in the mid-1980s. IMPROVE objectives are to provide data needed to assess the impacts of new emission sources, identify existing man-made visibility impairment, and assess progress toward the national visibility goals that define protection of the 156 Class I areas

. *

* See : http://views.cira.colostate.edu/web/Glossary.aspx 

## 2.1.13 Interpolation Interpolation is theprocess of estimating the air quality level in an unmonitored area by using one or more nearby air quality monitors. The technique used in MATS is called Voronoi Neighbor Averaging (VNA)

.Terminology & File Types

April 2014 Abt Associates Inc. 20 

## 2.1.14 Inverse Distance Weights Inverse distance weights is a weighting scheme where the weight given to any particular monitor is inversely proportional to its distance from the point of interest. Example, Inverse Distance Weights Assume there are four monitors (A, B, C, and D) that are a varying distance from a point E. Assume the distances are 10, 15, 15, and 20 kilometers respectively. The weights will be as follows:

Example, Inverse Distance Squared Weights Assume there are four monitors (A, B, C, and D) that are a varying distance from a point E. Assume the distances are 10, 15, 15, and 20 kilometers respectively. The weights will be as follows:Terminology & File Types

April 2014 Abt Associates Inc. 21 

## 2.1.15 Log File A Log File provides information on a variety of technical aspects regarding how a results file (*.ASR) was created. This includes the version of MATS, the date and time the *.ASR filewas created.Terminology & File Types

April 2014 Abt Associates Inc. 22 

## 2.1.16 Output Navigator The Output Navigator in MATS allows you to load results files that you have previously created. You can then view these data in maps and in tables, or export the data to text files, which you can then load into a program such as Excel. Additional details are in the Output NavigatorChapter.


## 2.1.17 Output File An Output File is one of the file types within a *.ASR results file . The types of Output Files available depend on the type of analysis (PM, Ozone , or Visibility ) and the output choices that you have specified in the Configuration File

. 

## 2.1.18 Point Estimate A point estimate is a calculation within MATS that is performed at (or near) the location of ambient air monitors. The output files will contain base and/or future year results at each valid monitoring location.


## 2.1.19 RRF The relative response factor is the ratio of the future year modeled concentration predicted near a monitor (averaged over multiple days) to the base year modeled concentration predicted near the monitor (averaged over the same days).


## 2.1.20 SANDWICH The SANDWICH process is used to adjust STNand IMPROVEmonitor data so that it is consistent with FRM monitor data. SANDWICH stands for S ulfates, A djusted Nitrates, D erived W ater, Inferred C arbonaceous mass, and estimated aerosol acidity ( H + ). *

* For more details, see : Frank, N., 2006: “ Retained Nitrate, Hydrated Sulfates, and Carbonaceous Mass in Federal Reference Method Fine Particulate Matter for Six Eastern U.S. Cities ” J. Air Waste Mange. Assoc., 56, 500-511. 

## 2.1.21 Scenario Name The Scenario Name is given to a set of results generated by MATS. The Scenario Name is used in several ways: (1) the results file ( *.ASR ) uses the Scenario Name; (2) an output folder, containing results extracted from a *.ASR file, is given the Scenario Name; and (3) the Output Filenames begin with the Scenario Name. The Scenario Name is specified when choosing the desired output, such as in the case of an ozone analysis.Terminology & File Types

April 2014 Abt Associates Inc. 23 

## 2.1.22 SMAT The Speciated Modeled Attainment Test (SMAT) is used to forecast PM 2.5 

### values. The main steps are as follows:

· Derive quarterly mean concentrations for each component of PM 2.5 

### by multiplying FRM PM 2.5 

### by fractional composition of each species;

· Calculate a model-derived relative response factor (RRF) for each species;

· Multiply each RRF times each ambient PM 2.5 

### component (for each quarter) to get the future concentrations;

· Sum the future quarterly average components; and

· Average the four mean quarterly future PM 2.5 

### concentrations.


## 2.1.23 Spatial Field A Spatial Field refers to air pollution estimates made at the center of each grid cell in a specified modeling domain. For example, MATS might calculate ozone design values forTerminology & File Types

April 2014 Abt Associates Inc. 24 

### each grid cell in the modeling domain. Several types of Spatial Fields can be calculated for ozone and PM. (See the sections for ozoneand PM for additional details.)


## 2.1.24 Spatial Gradient A Spatial Gradient is the ratio of mean model values at an unmonitored location over the mean model values at a monitor. Spatial Gradients can be used in the calculation of Spatial Fieldsfor ozone and PM. (See the sections for ozoneand PM for additional details.)


## 2.1.25 STN Monitors In meeting the requirements to monitor and gather data on the chemical makeup of fine particles, EPA established a Speciation Trends Network (STN). These STN monitors were placed at various national air monitoring stations (NAMS) and State and local air monitoring stations (SLAMS) across the Nation.


## 2.1.26 Temporal Adjustment A temporal adjustment refers to multiplying ambient monitor data with a model derived relative response factor (RRF) in order to generate an estimated future year concentration.


## 2.1.27 VNA Voronoi Neighbor Averaging (VNA) is an algorithm used by MATS to interpolate air quality monitoring data to an unmonitored location. MATS first identifies the set of monitors that best “surround” the center of the population grid cell, and then takes an inverse-distance weighted averageof the monitoring values.

2.1.27.1 VNA - Detailed Description Voronoi Neighbor Averaging (VNA) algorithm uses monitor data directly or in combination with modeling data. MATS first identifies the set of monitors that best “surround” the point of interest, and then takes an inverse-distance weighted average of the monitoring values.Terminology & File Types

April 2014 Abt Associates Inc. 25 

### In particular, MATS identifies the nearest monitors, or “neighbors,” by drawing a polygon, or “Voronoi” cell, around the center of the point of interest. The polygons have the special property that the boundaries are the same distance from the two closest points.Terminology & File Types

April 2014 Abt Associates Inc. 26 

### MATS chooses those monitors that share a boundary with the center of grid-cell “E.” These are the nearest neighbors, we use these monitors to estimate the air pollution level for this grid-cell.Terminology & File Types

April 2014 Abt Associates Inc. 27 

### To estimate the air pollution level in each grid-cell, MATS calculates an inverse-distance weighted average of the monitor values. The further the monitor is from the grid cell, the smaller the weight. In the figure below, the weight for the monitor 10 miles from the center of grid-cell E is calculated as follows:

The weights for the other monitors are calculated in a similar fashion. MATS then calculates an inverse-distance weighted average for grid-cell E as follows: Estimate = 0.35*80 ppb + 0.24*90 ppb+ 0.24*60 ppb + 0.18*100 ppb = 81.2 ppbTerminology & File Types

April 2014 Abt Associates Inc. 28 

## 2.2 File Types The primary results file generated by MATS has a .ASRextension, which is specific to MATS. To view the results you have generated in other programs (e.g., MS Excel), you can export .CSV files using the Output Navigator

.Overview of MATS Components

April 2014 Abt Associates Inc. 29 

## 3 

# Overview of MATS Components 3
Upon starting MATS for the first time, you will see the following main window.

There are three main tabs: Start , Map View , and Output Navigator . The Starttab allows you to calculate Annual and Daily PM, Ozoneand Visibilitylevels. The Map Viewtab allows to map your results. The Output Navigatortab allows you to view your results either as tables or maps. Finally, the Helpmenu at the top of the main window provides explanations and examples of all of the functionality in MATS. This Chapter gives a brief description of each of these items. All of these topics are covered in greater detail in subsequent chapters of this manual. 

## 3.1 Start The Start tab gives you the choice to analyze Particulate Matter (PM) , Ozoneor Visibility

. To begin, click on one of the three buttons. One of the key features of MATS is the Configuration. This is a reusable file that stores the choices that you have made when using MATS. You can use an existing Configuration File, make some minor changes to generate a new set of results, without having to explicitly set each of the choices you made in the previous Configuration.Overview of MATS Components

April 2014 Abt Associates Inc. 30 

### When you click on one of the analysis buttons, you will be asked whether you want to create a new Configuration, or whether you want to use an existing Configuration.

Make your choice and then click Go . MATS will then take you through a series of windows specifying the options available for each analysis.


## 3.1.1 Annual PM Analysis With the Standard Analysis, MATS can forecast annual PM2.5 design values at monitor locations. MATS can also calculate quarterly model data files and a species fractions file. The Choose Desired Outputwindow lets you specify the type of calculation(s) that you would like MATS to perform. These different assumptions are discussed in the Output Choicesection of the Annual PM Analysis: Details chapter.

In the Output Choice Advancedwindow, MATS lets you choose from among two main options: Spatial Field Estimatesand Miscellaneous Output that is generally used for quality assurance (QA). Within each of these two main options there are a number ofOverview of MATS Components

April 2014 Abt Associates Inc. 31 

### choices. Details regarding these choices are in the Output Choice - Advancedsection of the Annual PM Analysis: Details chapter.

In the Data Inputwindow, you specify the MATS input files that are used in each scenario. There are three main types of files which must be specified. These include ambient PM2.5 species data, ambient total PM2.5 data (FRM and IMPROVE), and gridded model output data (e.g. CMAQ or CAMx data). There is specific terminology that is used on the Data Input page. "Official" data refers to PM2.5 FRM data that can be used to determine official design values for compliance purposes (comparison to the NAAQS). Other datasets which may not have rigid regulatory significance are sometimes referred to as "unofficial" data. The format for the data is in the Data Inputsection of the Annual PM Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 32 

### The Species Fractions Calculation Optionshas two main sections. One involving speciated monitor data (e.g., STN and IMPROVE monitors) and the other total PM2.5 monitor data (FRM and IMPROVE). For each type of data you can specify the years of interest , whether you want to delete certain data , and the minimum amount of datafor a monitor to be considered "valid" (and thus included in the calculations). Details on these options arein the Species Fractions Calculation Options section of the Annual PM Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 33 

### The Species Fractions Calculation Options - Advancedscreen allows you to make relatively advanced choices for your analysis. Generally speaking, the default options settings are consistent with the EPA modeling guidance document (note: the start and end years should always be set to match the relevant base modeling year). One set of options allows you to specify the interpolation weighting that you want to use and whether the interpolation involves a maximum distance or not. The second set of options involves choices regarding ammonium, blank mass, and organic carbon. Details on these options
arein the Species Fractions Calculation Options - Advancedsection of the Annual PM Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 34 

### The PM2.5 Calculation Optionswindow allows you to specify the particular years of monitor data that you want to use from the input file you specified in the Data Input section. You can specify whether to use "official" or "custom" design values and whether monitors should have a minimum number of design values or a design value for a particular year. You can also specify how to calculate future NH4 levels. Details on these options arein the PM2.5 Calculation Optionssection of the Annual PM Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 35 

### You also can use the Model Data Optionsto specify how to use the model data. This is described in the Model Data Options section of the Annual PM Analysis: Details chapter.

The last step is to verify the inputs to the analysis.Overview of MATS Components

April 2014 Abt Associates Inc. 36 

## 3.1.2 Daily PM Analysis With the Standard Analysis, MATS can forecast daily PM2.5 design values at monitor locations. MATS can also calculate quarterly model data files and a species fractions file. The Choose Desired Outputwindow lets you specify the type of calculation(s) that you would like MATS to perform. These different assumptions are discussed in the Output Choicesection of the Daily PM Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 37 

### In the Output Choice Advancedwindow, MATS lets you choose from among a variety of options that are generally used for quality assurance (QA). Details regarding these choices are in the Output Choice - Advancedsection of the Daily PM Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 38 

### In the Data Inputwindow, you specify the MATS input files that are used in each scenario. There are three main types of files which must be specified. These include ambient PM2.5 species data, ambient total PM2.5 data (FRM and IMPROVE), and gridded model output data (e.g. CMAQ or CAMx data). There is specific terminology that is used on the Data Input page. "Official" data refers to PM2.5 FRM data that can be used to determine official design values for compliance purposes (comparison to the NAAQS). Other datasets which may not have rigid regulatory significance are sometimes referred to as "unofficial" data. The format for the data is in the Data Inputsection of the Daily PM Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 39 

### The Species Fractions Calculation Optionshas two main sections. One involving speciated monitor data (e.g., STN and IMPROVE monitors) and the other total PM2.5 monitor data (FRM and IMPROVE). For each type of data you can specify the years of interest , whether you want to delete certain data , and the minimum amount of datafor a monitor to be considered "valid" (and thus included in the calculations). Details on these options arein the Species Fractions Calculation Options section of the Daily PM Analysis: Detailschapter.Overview of MATS Components

April 2014 Abt Associates Inc. 40 

### The Species Fractions Calculation Options - Advancedscreen allows you to make relatively advanced choices for your analysis. Generally speaking, the default options settings are consistent with the EPA modeling guidance document (note: the start and end years should always be set to match the relevant base modeling year). A first set of options provides different options for choosing peak monitor days. A second set of options allows you to specify the interpolation weighting that you want to use and whether the interpolation involves a maximum distance or not. The third set of options involves choices regarding ammonium, blank mass, and organic carbon. Details on these options
arein the Species Fractions Calculation Options - Advancedsection of the Daily PM Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 41 

### The PM2.5 Calculation Optionswindow allows you to specify the particular years of monitor data that you want to use from the input file you specified in the Data Input section. You can specify whether monitors should have a minimum number of design values or a design value for a particular year. You can also specify how to calculate future NH4 levels. Details on these options arein the PM2.5 Calculation Optionssection of the Daily PM Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 42 

### You also can use the Model Data Optionsto specify how to use the model data. This is described in the Model Data Options section of the Daily PM Analysis: Details chapter.

The last step is to verify the inputs to the analysis.Overview of MATS Components

April 2014 Abt Associates Inc. 43 

## 3.1.3 Ozone Analysis MATS can forecast ozone design values at monitor locations -- these forecasts are referred to as Point Estimates . MATS can also use a variety of approaches to calculate design values for a Spatial Field . The Choose Desired Outputwindow lets you specify the type of calculation(s) that you would like MATS to perform. These different assumptions are discussed in the Choose Desired Outputsection of the Ozone Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 44 

### The Data Inputwindow lets you specify the data files that you want to use. MATS comes populated with default data sets, but you can use your own data if you choose. The format for the data is in the Data Inputsection of the Ozone Analysis: Detailschapter. The Data Inputwindow also lets you choose how to use model data when calculating a temporal adjustment at a monitor. This is discussed in detail in the Using Model Data section of the Ozone Analysis: Detailschapter.Overview of MATS Components

April 2014 Abt Associates Inc. 45 

### The Filtering and Interpolationwindow lets you specify the years of data that you want to use, any restrictions you want to apply when choosing valid monitors ( i.e. , monitors that MATS use in its calculations), and options on the interpolationmethod. This is discussed in detail in the Filtering and Interpolationsection of the Ozone Analysis: Detailschapter.Overview of MATS Components

April 2014 Abt Associates Inc. 46 

### The RRF and Spatial Gradientwindow lets you set parameters used in the calculation of relative response factors (RRF) and spatial gradients . This is discussed in detail in the RRF and Spatial Gradient section of the Ozone Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 47 

### The last step is to verify the inputs to the analysis.Overview of MATS Components

April 2014 Abt Associates Inc. 48 

## 3.1.4 Visibility Analysis MATS can forecast visibility in Class I Areas - these forecasts are referred to as Point Estimates . In addition to specifying the Scenario Name , you can choose the version of the IMPROVE Algorithmthat you want to use. You can also choose whether to use model data at the monitor linked to each Class I Area, or whether to use model data closest to the Class I Area centroid. These different assumption are discussed in the Desired Output section of the Visibility Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 49 

### The Data Inputwindow lets you specify the data files that you want to use. MATS comes populated with default input data, but you can use your own data if you choose. The format for the data is in the Data Inputsection of the Visibility Analysis: Details chapter. The Data Inputwindow also lets you choose how to use model data when calculating a temporal adjustment at a monitor. This is discussed in detail in the Using Model Data section of the Visibility Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 50 

### The Filteringwindow lets you specify the years of data that you want to use, and any restrictions you want to apply when choosing valid monitors ( i.e. , monitors that MATS use in its calculations). This is discussed in detail in the Filteringsection of the Visibility Analysis: Details chapter.Overview of MATS Components

April 2014 Abt Associates Inc. 51 

### The last step is to verify the inputs to the analysis.Overview of MATS Components

April 2014 Abt Associates Inc. 52 

## 3.2 Output Navigator
The Output Navigatorallows you to load results files ( i.e. , ASR files ) that you have previously created in MATS. You can view these data in maps and in tables, or export the data to text files that you can then work with in a program such as Excel. To start, just click on the Output Navigatortab. Then click on the Loadbutton to choose the file that you want to examine. You can click the Extract Allbutton, and MATS will create a folder with all of the files that MATS has generated. (A default name for the folder is the Scenario Nameyou have chosen.)

The files generated by MATS are of two types: (1) Configurationand Logfiles; and (2) Outputfiles containing the results of the MATS calculations.

Another option is to right-click on a particular file, and then you can choose whether to use data to Add to Map , View , or Extract

.Overview of MATS Components

April 2014 Abt Associates Inc. 53 

### The Viewoption lets you examine the data and then to export it to a CSVfile, which you can then load into another program such as Microsoft Excel.Overview of MATS Components

April 2014 Abt Associates Inc. 54 

### Choosing the Extract option will allow you to immediately export the data to a CSV file. The default file name for the CSV file is the same one that you see in the Output Navigator window ( e.g. , Example O3 - Ozone Monitors -- monitor data.csv ). Finally, choosing the Add to Mapoption allows you to create a map of your results. 

## 3.3 Map View
The Map Viewallows you to perform a variety of mapping tasks. You can zoom in to a particular location; choose particular colors to map your data, export the maps you have created to BMP files , among other things. These various options are discussed in detail in the Map Viewchapter.



## 3.4 Help The Help dropdown menu has the User Manual for MATS and version information.Overview of MATS Components

April 2014 Abt Associates Inc. 55Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 56 

## 4 

# Annual PM Analysis: Quick Start Tutorial 4
In this tutorial you will forecast annual PM2.5 design values at monitors in the Eastern United States. The steps in this analysis are as follows:

· Step 1. Start MATS . Start the MATS program and choose to do an Annual PM analysis.

· Step 2. Output Choice . Choose the output to generate. In this example, you will do two things: forecast annual PM2.5 levels at monitor locations and output a species fractions file (which you can subsequently reuse, as discussed here ).

· Step 3. Output Choice - Advanced . With these advanced options, you can generate spatial fields and a variety of files useful for quality assurance. Simply review these options and then uncheck them all. (If you are interested, these options are all described here .)

· Step 4. Data Input . Choose the particular years of data and monitors to use in this analysis.

· Step 5. Species Fractions Calculation Options . Specify how to generate the relative response factors (RRFs) used in the forecasts.

· Step 6. Species Fractions Calculation Options - Advanced . This window allows you to make relatively advanced choices for your analysis, such as choosing different ways to interpolate the monitor data.

· Step 7. PM2.5 Calculation Options . Among other things you can specify the particular years of monitor data that you want to use.

· Step 8. Model Data Options . Choose how to use the model data, such as determining the maximum distance the model data can be from a monitor.

· Step 9. Final Check . Verify the choices you have made.

· Step 10. Map Output . Prepare maps of your forecasts.

· Step 11. View & Export Output . Examine the data in a table format.

Each step is explained below. Additional details are provided in the section Annual PM Analysis: Details

. 

## 4.1 Step 1. Start MATS Double-click on the MATS icon on your desktop, and the following window will appear:Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 57 

### Click the Annual PM Analysisbutton on the main MATS window. This will bring up the Configuration Managementwindow.

A Configurationallows you to keep track of the choices that you make when using MATS. For example, after generating results in MATS, you can go back, change one of your choices, rerun your analysis, and then see the impact of this change without having to enter in all of your other choices. For this example, we will start with a New Configuration

. Choose Create New Configurationand click the Gobutton. This will bring up the Choose Desired Outputwindow. 

## 4.2 Step 2. Output Choice
The Choose Desired Outputwindow allows you to choose the output that you would likeAnnual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 58 

### to generate. MATS allows you to conduct a Standard Analysis (i.e., forecast Point Estimates at ambient monitors), output quarterly model data, and output a species fractions file.

· In the Scenario Namebox type “ Tutorial Annual PM ”

–this will be used to keep track of where your results are stored and the variable names used in your results files.

· Standard Analysis . Leave the box checked next to "Interpolate monitor data to FRM monitor sites. Temporally-adjust." MATS will create forecasts for each monitor in the monitor file. (Additional details are in the Standard Analysissection.)

· Quarterly Model Data . Uncheck these options. (If checked, MATS generates quarterly model files that MATS generates from daily data that you have provided. This is useful if you want to reuse model files -- the quarterly files are much smaller and MATS will run faster if it can skip the step of creating quarterly data from the daily. These files are described here .)

· Species Fraction . Check the box next to Output species fractions file . This will generate a reusable file described here

.

· Actions on run completion . Check the box next to Automatically extract all selected output files . Upon completing its calculations, MATS will extract the results into a folder with the name of your scenario.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 59 

### When your window looks like the window above, click Next . This will bring you to the Output Choice - Advancedwindow. 

## 4.3 Step 3. Output Choice - Advanced With the advanced options in the Output Choice - Advancedwindow, you can generate spatial fields and a variety of files useful for quality assurance. Simply review these options and then uncheck them all. (If you are interested, these options are all described here .)Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 60 

### When your window looks like the window above, click Next . This will bring you to the Data Inputwindow. 

## 4.4 Step 4. Data Input
The Data Inputwindow allows you to choose the species and PM2.5 monitor data and the model data that you want to use. As discussed in more detail in the following chapter (see Standard Analysis ), MATS calculates the ratio of the base and future year model data to calculate a relative response factor ( RRF) for each PM species. MATS uses the PM2.5 monitor data and interpolated species monitor data to estimate species values at each FRM site, multiplies the species values from the monitor data with the species-specific RRFs, and then estimates a future-year design value. (Additional details on Data Input are available here .) Use the default settings in the Data Inputwindow. The window should look like the following:Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 61 

### When your window looks like the window above, click Next . This will bring you to the Species Fractions Calculation Options window. 

## 4.5 Step 5. Species Fractions Calculation Options
TheSpecies Fractions Calculation Optionswindow has several functions related to the IMPROVE-STN (species) monitor data and the (unofficial) PM2.5 monitor data. These functions include identifying the years of monitor data that you want to use, deleting any specific data values, and choosing the minimum data requirements of monitors you want in your analysis.

· Monitor Data Years

. Choose the years of monitor data that you want to use. The default is to use the three-year period 2006-2008. (That is, for both IMPROVE-STN and PM2.5 monitor data, the Start Yearis 2006 and the End Yearis 2008 .) The default period is based on a modeling year of 2007. The start and end years should be changed to applicable time periods, depending on the base modeling year.

· Delete Specified Data Values

. The default is to delete the observations specified by EPA. As described in the Data Input section , valid data are given a value of "0" and observations that should be deleted are given a value of "1" to "10". (Leave unchecked theoption for the user to flag data.)

· Minimum Data Requirements

. There are three sets of minimum data requirements: 1. Minimum number of valid days per valid quarter . This is the minimum number of site-days per valid quarter. The default is 11 days, which corresponds to > 75% completeness for monitors on a 1 in 6 day schedule. This is a minimum number of samples that is routinely used in calculations of quarterly averageAnnual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 62 

### concentrations. 2. Minimum number of valid quarters required for valid season . This number of years of data (within the start year and end year specified) for which we have valid quarters for a given season. The default value is 1 year. If the value is set = 2, then there will need to be 2 years of valid data from quarter1 in order for quarter one to be considered complete (and the same for the other 3 quarters). 3. Minimum number of valid seasons required for valid monitor . This is the number of valid seasons that are needed in order for a particular monitor's data to be considered valid. The default is 1 for IMPROVE-STN monitor data and the range is 1-4. For example, if the value is = 1, then a monitor's data will be used in the species fractions calculations if it has at least one valid season. If the value = 4, then the site must have all 4 seasons of valid data to be used. The default for PM2.5 depends on whether the data are used in point calculations (default = 4) or spatial field calculations (default = 1). Use the default settings pictured in the screenshot below. (All of these options are described in detail here .)Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 63 

### When your window looks like the window above, click Next . This will bring you to the Species Fractions Calculation Options window. 

## 4.6 Step 6. Species Fractions Calculation Options - Advanced
The Species Fractions Calculation Options - Advancedscreen allows you to make relatively advanced choices for your analysis. Generally speaking, the default options settings are consistent with the EPA modeling guidance document. One set of options allows you to specify the interpolation weighting that you want to use and whether the interpolation involves a maximum distance or not. The second set of options involves choices regarding ammonium, blank mass, and organic carbon.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 64 

### Use the default settings pictured in the screenshot below. (All of these options are described in detail here .)

When your window looks like the window above, click Next . This will bring you to the PM2.5 Calculation Optionswindow. 

## 4.7 Step 7. PM2.5 Calculation Options
The PM2.5 Calculation Optionswindow allows you to specify the particular years of monitor data that you want to use from the input file you specified in Step 4(Data Input). Keep the default settings:

· PM2.5 Monitor Data Years

. Start Year = 2005and End Year = 2009

.

· Official vs. Custom Values . Specify "official" design values, which is the recommended default setting.

· Valid FRM Monitors . Keep the minimum number of design values equal to the default value of 1, and do not specify any particular design values for inclusion in the calculations.

· NH4 Future Calculation . You can also specify how you want to forecast NH4 values. Use the default approach, which is to use baseline DON values.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 65 

### Use the default settings pictured in the screenshot below. (All of these options are described in detail here .)

When your window looks like the window above, click Next . This will bring you to the Model Data Options window. 

## 4.8 Step 8. Model Data Options
The Model Data Optionssection allows you to specify the Temporal Adjustment at Monitor.This option specifies how many model grid cells to use in the calculation of RRFs for point estimates and for spatial estimates. Use the default option: 3x3 set of grid cells. Note that for PM analyses, MATS calculates meanconcentrations across the grid cell array (as compared to maximum concentrations used for ozone analyses). Use the default settings pictured in the screenshot below. (All of these options are described further here .)Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 66 

### When your window looks like the window above, click Next . This will bring you to the Final Check window. 

## 4.9 Step 9. Final Check
The Final Checkwindow verifies the choices that you have made. For example, it makes sure that the paths specified to each of the files used in your Configurationare valid. Click on the Press here to verify selectionsbutton.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 67 

### If you encounter any errors, go back to the choices you have previously made by clicking on the appropriate part ( e.g. , Data Input) of the tree in the left panel, and then make any changes required. When your window looks like the window above, click either Save Scenario & Runor Save Scenario. Save Scenario & Run will cause MATS to immediately run the scenario. A temporary, new Runningtab will appear (in addition to the Start , Map Viewand Output Navigatortabs).Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 68 

### When the calculations are complete, a small window indicating the results are Donewill appear. Click OK

.

After clicking OK , MATS will open a folder with the results files already exported.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 69 

### Output Navigatortab will also be active. (The Runningtab will no longer be seen.) MATS will automatically load the output files associated with the .asr configuration that just finished running.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 70 

### The next step ( click here ) shows you how to map your results with the Output Navigator

. For more details on mapping and other aspects of the Output Navigator , there is a separate chapter on the Output Navigator

. 

## 4.10 Step 10. Map Output After generating your results, Output Navigatorcan be used to load and/or map them. If a run just finished, the output files will already be loaded into output navigator. If files from a previous run need to be loaded then click on the Loadbutton and choose the Tutorial Annual PM.asr file.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 71 

### Under Configuration/Log Files , you will see two files:

· Configuration : keeps track of the assumptions that you have made in your analysis.

· Log File : provides information on a variety of technical aspects regarding how a results file (*.ASR) was created. Under Output Filesyou will see:

· Tutorial Annual PM Quarterly Avg Spec Frac Point : contains species fractions and interpolated species values. (Note that this is a reusable file that you can load into MATS.)

· Tutorial Annual PM Annual PM25 Point : contains base & future PM2.5, species values, and RRFs. (Note that the annual RRFs and annual species values are not used anywhere in the calculation of design values, and here just for information.) Right-click on the file Tutorial Annual PM Annual PM25 Point . This gives you three options: Add to Map , View , and Extract . Choose the Add to Mapoption.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 72 

### This will bring up the Map Viewtab.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 73 

### To view an enlarged map, use the Zoom to an areaTask Bar button on the far left. Choose the Continental US

.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 74 

### To more easily view the location of monitors in particular states, uncheck US Counties using the Standard Layersdrop down menu on the far right of the Task Bar. Your window should look like the following:Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 75 

### Zoom in further on the Eastern US using the Zoom inbutton on the Task Bar. This allows you to view the results more closely. A dashed line surrounds the area that you have chosen and should look something like the following:Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 76 

### Right click on the " Tutorial Annual PM Annual PM25 Point " layer in the panel on the left side of the window. Choose the Plot Valueoption.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 77 

### This will bring up Shape Class Breakswindow. In the Valuedrop-down list, choose the variable " f_pm25_ann_dv " -- this is forecasted PM2.5 design value.

Click Applyand then click Close . This will bring you back to the Map Viewwindow.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 78 

### This is just a brief summary of the mapping possibilities available. For more details, there is a separate chapter on the Map View . The next stepis to go to the Output Navigatorto view the data in a table format. 

## 4.11 Step 11. View Output After mapping your results, click on the Output Navigatortab, so that you can then view the data in a table. Right-click on the file Tutorial Annual PM Annual PM25 Point . This gives you three options: Add to Map , View , and Extract . Choose the Viewoption.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 79 

### This will bring up a Monitor Network Datatab. The upper left panel allows you to view the ID and latitude and longitude of the monitors in your data -- at the right of this panel there is a scrollbar with which you can locate any particular monitor of interest.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 80 

### To view the data for a particular monitor -- in this example, monitor ID = "010491003" -- highlight this monitor. MATS will then display the values for this monitor in the bottom panel.Annual PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 81 

### To view all of the data again, click on the Show Allbutton. For additional details on generating annual PM results, see the chapter on Annual PM Analysis: Details . For additional details on viewing data, see the View Data section in chapter on the Output Navigator

.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 82 

## 5 

# Annual PM Analysis: Details 5
MATS can forecast annual design values at PM2.5 monitor locations -- these forecasts are referred to as Point Estimates . MATS can also use a variety of approaches to calculate design values for a Spatial Field . A Spatial Field refers to a set of values comprising calculations for each grid cell in a modeling domain from Eulerian grid models such as CMAQ and CAMx. The set of choices involved in calculating either Point Estimates or a Spatial Field can be fairly involved, so MATS keeps track of these choices using a Configuration . When you begin the process of generating PM2.5 estimates, MATS provides an option to start a new Configuration or to open an existing Configuration.

Select your option and then click Go

. MATS will then step you through a series of windows with choices for your analysis.

· Output Choice . Choose whether you want to run the Standard Analysis, and whether to output a species fractions file and/or quarterly model data.

· Output Choice - Advanced . This option provides miscellaneous Point Estimate output files, as well as baseline and forecast year Spatial Fields and gradient-adjusted output.

· Data Input
. Load species monitoring data or a species fractions file. Load PM2.5 ambient monitoring data. Finally, load the modeling data that you want to use.

· Species Fractions Calculation Options . Choose the years of daily STN-IMPROVE and FRM monitoring data. Identify valid monitors. Delete specified values.

· Species Fractions Calculation Options - Advanced . Choose interpolation options for PM2.5 and species monitoring data. Choose assumptions for the ammonium calculation, default blank mass, and organic carbon.

· PM2.5 Calculation Options - FRM Monitor Data . Choose the years of quarterly FRM monitoring data. Choose whether to use official design values or custom design values. Identify valid monitors. Choose the approach for calculating future NH4.

· Model Data Options . Specify the maximum distance of monitors from modeling domain. Specify which model grid cells will be used when calculating RRFs at monitor locations.

· Final Check . Verifythe selections that you have made.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 83 

## 5.1 Output Choice
In the Output Choicewindow, MATS lets you specify the name of your Scenario , and then to choose up to three options: Standard Analysis , which refer to forecasts made at FRM PM2.5 monitor locations; Quarterly Model Data , which allows you to create quarterly averages from daily model output data (output data from grid models such as CMAQ and CAMx), and then subsequently reuse this file; and Species Fractions , which outputs a reusable species fractions file. By checking the box next to Automatically extract all selected output files, MATS will create a separate folder with your chosen Scenario Name in the MATS "Output" folder, and then export .CSV files with the results of your analysis. Alternatively, you can export the results from the Output Navigator , but checking this box is a little easier.

Standard Analysis . The Standard Analysisrefers to the calculation of future year PM2.5 design values at FRM monitor locations. This is the main part of the modeled attainment test for PM2.5. There are several calculations involved in this analysis. MATS will interpolate PM2.5 species data, calculate species concentrations at each FRM site and project design values to a future year using gridded model data. Most MATS users will run this analysis and it is therefore checked by default. Quarterly Model Data . MATS requires two types of data input : ambient monitor data and gridded model output data. For the annual PM2.5 calculations, MATS will accept either MATS formatted daily average gridded model files or quarterly average files. If daily average model files are used as inputs, MATS will calculate quarterly averages from the daily averages and optionally output the quarterly average concentrations into text filesAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 84 

### (CSV files). The quarterly average text files can then be re-used in subsequent MATS analyses. Quarterly average input files are smaller and run faster than daily average files. There are two options to output quarterly average model concentration CSV files:

· Check the “Output quarterly average model data file” box to create quarterly average CSV for allgrid cells in the modeling domain. MATS will create one baseline year file and one future year file. This will create relatively large files, but they will still be ~90 times smaller than daily average files (assuming a full year of model data).

· The second option is to check the “Output used quarterly average model data file”. This option will only output the grid cells that are subsequently usedin the particular MATS configuration. For example, if MATS calculates future year design values at 20 FRM sites using a 1 X 1 grid array, then MATS will output base and future model values for only 20 grid cells (assuming each monitor is in a unique grid cell). The advantage of these files is that they are extremely small. But if subsequent MATS runs use a different set of monitors or grid arrays, then the files may not contain all of the necessary data to complete the analysis. This option is recommended as a QA tool to examine the grid cells and the model concentrations that MATS is using in the analysis. Species Fraction . Checking the “ Output species fraction file” box will create an output file containing the calculated PM2.5 species fractions at each FRM site used by MATS. This species fraction file can be re-used in MATS as an input file. The species fraction file can be useful for several reasons. One, using a species fraction file saves time because MATS won ’ t have to interpolate species data and calculate fractions each time it is run. Two, it can provide consistency between MATS runs by ensuring that the same species fractions are used each time. And for the same reason, the species fraction file can be used interchangeably between different users to ensure that multiple groups are using the same species fractions (if that is a goal). And finally, the fractions file can serve as a template for creating a custom species fractions file using whatever data and techniques (e.g. alternative interpolation techniques) are desired by any particular user. 

## 5.1.1 Scenario Name The Scenario Name allows you to uniquely identify each analysis that you conduct. It is used in several ways.

· Results file name . The results file is given the Scenario Name(e.g., Example Annual PM.asr). Note that the extension ( .ASR ) is specifically designated just for MATS and can only be used by MATS.

· Organize output . In the Output folder, MATS will generate a folder using the Scenario Name . MATS will use this folder as a default location for files generated with this Scenario Name.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 85 

### · Output file names . The output files generated will begin with the Scenario Name.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 86 

## 5.1.2 Standard Analysis Future-year PM2.5 design values are calculated at each FRM monitoring site through a series of calculations: Step 1

. Baseline quarterly average PM2.5 calculationat each FRM monitor site; Step 2

. Baseline quarterly average species calculationusing the quarterly weightedaverage baseline PM2.5 concentration and species fractions at each FRM monitor site; Step 3

. Forecasted quarterly average species calculationusing relative response factors (RRFs) at each FRM monitor site; Step 4

. Forecasted design value calculationat each FRM monitor site. In this section, we go into some detail describing these steps. However, you should note that MATS gives you a number of options affecting the exact steps that MATS follows, such as determining which years of monitoring data to use and to choosing which monitors to include in the calculations. These options are detailed in the PM2.5 Calculation Options section. The output from the Standard Analysis is described here

. 5.1.2.1 Step 1: Baseline Quartelry Average PM2.5 Calculation The first step in the Standard Analysis is to calculate baseline PM2.5 levels using the ("official") quarterly average PM2.5 file (described in the Data Input section ). MATS uses these quarterly values to calculate 3-year averages of consecutive years of data for each quarter, and then to average these averages to get a single PM2.5 estimate for each quarter. Example Calculation Baseline PM2.5 Concentration Starting with the following quarterly values: Quarter 2005 2006 2007 2008 2009 Q1 11.8188 10.7107 9.7133 10.6966 9.9839 Q2 13.2400 11.1333 9.3138 15.1655 9.6680 Q3 18.7960 11.0700 12.6652 12.0667 14.4964 Q4 14.2579 9.4032 9.7903 10.7414 11.2778 

### MATS calculates 3-year averages of consecutive years of data for each quarter: Quarter 2005-2007 2006-2008 2007-2009 Q1 10.7476 10.3735 10.1313 Q2 11.2290 11.8709 11.3824 Q3 14.1771 11.9340 13.0761 Q4 11.1505 9.9783 10.6032 

### MATS averages the 3-year averages to get a single estimate for each quarter:Annual PM Analysis: Details

April 2014 Abt Associates Inc. 87 Quarter Avg Q1 10.4175 Q2 11.4941 Q3 13.0624 Q4 10.5773



### 5.1.2.2 Step 2: Baseline Quarterly Average Species Calculation Since the FRM monitors do not have speciated data (and the majority of FRM sites are not co-located with a speciation monitor), MATS uses speciated PM2.5 monitor data from other monitoring networks, such as STN and IMPROVE, to estimate the PM2.5 attributable to the following species: sulfate (SO4), nitrate (NO3), elemental carbon (EC), organic carbon (OC), crustal matter, particle bound water (PBW), ammonium (NH4), and, data permitting, salt. Note that the process of calculating species fractions is involved and discussed in detail in the Species Fractions Calculations & Output section of this user manual. Nevertheless, the use of species fractions to calculate species concentrations is straightforward. The weighted quarterly species average is calculated by multiplying weighted quarterly average FRM baseline values (minus the assumed blank mass, specified by the user) with species fractions that have been estimated for each FRM monitor. The calculation is as follows:

Note that MATS calculates species fractions from speciated monitors for a limited number of years. As a result, rather than have species fractions specifically calculated for each quarter and each year, MATS uses a single set of species fractions to calculate the weighted quarterly average species concentrations. The species data should be "representative" of the species fractions that occur during the 5 year FRM monitoring period selected in MATS. Example Calculation Baseline Species Concentrations MATS multiplies the (non-blank) baseline quarterly PM2.5 values:
FRM PM2.5 Blank Mass Non-Blank Mass
10.4175 0.5 9.9175 11.4941 0.5 10.9941Annual PM Analysis: Details

April 2014 Abt Associates Inc. 88 13.0624 0.5 12.5624 10.5773 0.5 10.0773 

### with the species fractions calculated for this particular site: Quarter SO4 NO3 OCMMB EC PBW NH4 Crustal (Salt) Q1 0.2382 0.1108 0.3346 0.0201 0.1049 0.1209 0.0705

-- Q2 0.2637 0.0727 0.3178 0.0545 0.1095 0.1273 0.0545

-- Q3 0.1432 0.0557 0.5621 0.0238 0.0959 0.0955 0.0238

-- Q4 0.2580 0.1389 0.2756 0.0396 0.1094 0.1190 0.0595

-- 

### The product is the estimated baseline species concentrations by quarter. Quarter SO4 NO3 OCMMB EC PBW NH4 Crustal Q1 2.3623 1.0989 3.3184 0.1993 1.0403 1.1990 0.6992 Q2 2.8991 0.7993 3.4939 0.5992 1.2039 1.3996 0.5992 Q3 1.7989 0.6997 7.0613 0.2990 1.2047 1.1997 0.2990 Q4 2.5999 1.3997 2.7773 0.3991 1.1025 1.1992 0.5996

Baseline Calculation - General 

### MATS does several calculations to generate the species concentrations used to calculate species fractions. In general, calculation of the concentrations of SO4, NO3, EC, crustal, and salt are straightforward. The concentrations are derived directly from the ambient data file or an interpolation of that data. However, the calculation of ammonium, particle bound water (PBW) and organic carbon (OC) are more complicated and calculated internally in MATS (as discussed in the following sections). MATS uses speciated monitor data to estimate individual species fractions at FRM sites using the “SANDWICH” process (Frank, 2006) (SANDWICH stands for Sulfates, Adjusted Nitrates, Derived Water, Inferred Carbonaceous mass, and estimated aerosol acidity [H+]). The data input to the PM calculations in MATS includes quarterly FRM monitor data and speciated monitor data from STN and IMPROVE sites that has been partially adjusted to match the anomalies in FRM data (e.g., nitrate volatilization). The default species input data file contains aerosol nitrate data (NO3r) that has been adjusted to account for volatilization. Additional SANDWICH adjustments are made within MATS. These include calculation of particle bound water (PBW) and organic carbon by mass balance (OCMmb). When there is more than one year of speciated data, MATS will create quarterly average species levels for each year at each monitor, and then average the seasonal values across the available years to get a single estimate for each species for each quarter at each monitor. (See the section on Species Fractions Calculation Options for additional details on how multiple years of speciated monitor data are combined.)Annual PM Analysis: Details

April 2014 Abt Associates Inc. 89 

### Note that MATS can calculate quarterly species concentrations at FRM monitor sites or a spatial field. MATS will allow you to reuse the species fractions file for point estimates or spatial fields. And in addition to calculating species fractions with monitor data -- on the Output Choice - Advancedwindow, you can choose gradient-adjusted species fractions, which are based on monitor plusmodel data. Interpolation About 75 percent of FRM monitors are not co-located with an STN monitor, so the estimation of the quarterly averages of the individual species at those FRM sites depends on theinterpolatedquarterly averages from speciated monitors (e.g., STN). Individual species are interpolated to the latitude and longitude associated with each FRM monitor. (For FRM monitors that areco-located with an STN monitor, MATS simply uses the species values from the co-located STN monitor.) You can find details on the interpolation process and different options for interpolation at the section on Interpolation Options for Species Fractions Calculation

. Calculations After Interpolation After the interpolation of quarterly averages for retained NO3 (NO3r), SO4, OCM, crustal, EC, and DON, a few additional steps are necessary to generate speciated quarterly averages at each FRM monitor site. These include calculating retained NH4 (NH4r), PBW, blank mass, and organic carbon mass (OCMMB), the latter of which is calculated through a mass balance approach. Summary of Calculations After Interpolation of STN & IMPROVE Speciated Monitor Data Calculation Description Calculate Retained Ammonium (NH4r) Calculate ammonium associated with retained nitrate (NO3r) and SO4. MATS calculates NH4r using DON, SO4, and NO3r. (Alternatively MATS can use directed measured ammonium). Calculate Particle Bound Water (PBW) Calculate amount of water associated with ammonium sulfate and ammonium nitrate, which are hygroscopic. Estimate Blank Mass Account for contamination in FRM monitors. Calculate Organic Carbon Mass (OCMMB) Calculate organic carbon mass with a mass balance approach. Calculate Species Fractions Divide species estimates for SO4, NO3r, OCMMB, EC, crustal material, NH4r, and PBW by the non-blank PM2.5 mass. (The inclusion of salt is optional and is not included in the default MATS data.)


### The following sections describe the calculations of ammonium, PBW, and organic carbon (by difference).

Retained Ammonium Calculation 

### MATS calculates retained ammonium two different ways. The default approach is to use interpolated degree of neutralization of sulfate (DON) values from the speciated monitors. The alternative approach is to use interpolated NH4 values from speciated monitors (e.g.,Annual PM Analysis: Details

April 2014 Abt Associates Inc. 90 

### STN). In the Species Fractions Calculations Options - Advancedsection, you have the option to choose the approach that you prefer to use. The two approaches are described here. Default approach using measured pre-calculated DON, SO4, and retained NO3 (NO3r): Because of uncertainties in NH4 speciation measurements, by default MATS calculates ammonium values using the degree of sulfate neutralization (DON). MATS uses precalculated daily DON values that are included in the species data input file ("Species-forfractions-xxxx.csv"). The values for DON are calculated from the amount of ammonium associated with sulfate (NH4 SO4 

### ) as follows:

And the estimated NH4 SO4

### is calculated as follows:

where 0.29 is the molar ratio of NH4 to NO3 and NH4 measured

### and NO 3 retained

### reflect the amounts of NH4 and NO3 retained on the FRM filter. The amount of NH4 SO4

### is not allowed to exceed the fully neutralized amount of 0.375 multiplied by the estimated sulfate ion concentration. MATS then calculates ammonium using interpolated monitor values of DON, SO4, and NO3r as follows:

Alternative Approach Using Measured Ammonium . The alternative approach is to use interpolated NH4 values from STN monitors. This approach has several steps. First, MATS calculates “adjusted” NH4:

where the PctEvap factor refers to the percentage of ammonium associated with the volatilized nitrate that is also lost. (As discussed in the Species Fractions Calculation Options - Advancedsection, this factor is adjustable from 0 to 100 percent.) The default assumption is that no ammonium is volatilized (0 percent). Second, MATS calculates NH4 associated with SO4:

Third, MATS calculates DON:Annual PM Analysis: Details

April 2014 Abt Associates Inc. 91 

### Finally, using the same equation as in the default approach, MATS calculates NH4r by substituting the calculated DON for the interpolated (measured) DON value:

Particle Bound Water Calculation 

### Because ammoniated sulfate and ammonium nitrate are hygroscopic, the retained sulfate and nitrate mass will include water. Particle bound water (PBW) is estimated using the Aerosol Inorganic Model (AIM) (Clegg et al, 1998). For computational convenience, a polynomial regression equation was fit to the calculated water mass from AIM and the three input values that fed into AIM (sulfate, nitrate and ammonium). AIM was run with typical FRM filter equilibration conditions of 35% RH and 22 deg C (295 deg K). MATS calculates particle-bound water (PBW) using levels of SO4, NO3r, and NH4r as follows. (Note that this is the same equation that MATS uses to calculate future-year PBW, the difference being the future-year PBW uses future-year values of SO4, NO3r, and NH4r, and here MATS uses base-year values.) The calculation uses one of two equations, depending on the acidity of the ammoniated sulfate (represented by DON). S, N, and A in the equations are the relative fraction of SO4, NO3r, and NH4r respectively. S = SO4 / (SO4 + NO3r + NH4r); N = NO3r / (SO4 + NO3r + NH4r); A = NH4r / (SO4 + NO3r + NH4r); if DON le 0.225 then PBW = {595.556 - 1440.584*S - 1126.488*N + 283.907*(S**1.5) - 13.384*(N**1.5) - 1486.711*(A**1.5) + 764.229*(S**2) + 1501.999*(N*S) + 451.873*(N**2)Annual PM Analysis: Details

April 2014 Abt Associates Inc. 92 

### - 185.183*(S**2.5) - 375.984*(S**1.5)*N - 16.895*(S**3) - 65.814*(N**1.5)*S + 96.825*(N**2.5) + 83.037*(N**1.5)*(S**1.5) - 4.419*(N**3) + 1720.818*(A**1.5)*S + 1220.383*(A**1.5)*N - 311.496*(A**1.5)*(S**1.5) + 148.771*(A**1.5)*(N**1.5) + 1151.648*(A**3)} * (SO4+NO3r+NH4); ELSE PBW = {202048.975 - 391494.647 *S - 390912.147 *N + 442.435 *(S**1.5) - 155.335 *(N**1.5) - 293406.827 *(A**1.5) + 189277.519 *(S**2) + 377992.610 *N*S + 188636.790 *(N**2) - 447.123 *(S**2.5) - 507.157 *(S**1.5)*N - 12.794 *(S**3) + 146.221 *(N**1.5)*S + 217.197 *(N**2.5) + 29.981 *(N**1.5)*(S**1.5)Annual PM Analysis: Details

April 2014 Abt Associates Inc. 93 

### - 18.649 *(N**3) + 216266.951 *(A**1.5)*S + 215419.876 *(A**1.5)*N - 621.843 *(A**1.5)*(S**1.5) + 239.132 *(A**1.5)*(N**1.5) + 95413.122 *(A**3)} * (SO4+NO3r+NH4) . Organic Carbon Mass Calculation 

### Measured organic carbon mass is not directly used in the calculation of species fractions in MATS because of (1) many uncertainties in estimating carbonaceous mass from carbon measurements (Turpin & Lim, 2001; Chow et al, 2004) (2) differences in carbon measurement protocol between urban and rural monitoring locations, (3) a relatively “bumpy” surface of urban carbon concentrations as derived from urban and rural organic carbon measurements and (4) lack of carbon measurements at all FRM locations. The MATS approach estimates carbon by mass balance comparing precisely measured FRM PM2.5 mass (EPA, 2003) with the sum of its non-carbon components. Total carbonaceous mass contains both elemental carbon (EC) and organic carbon mass (OCM). We measure EC from the interpolated STN and IMPROVE monitors, while we calculate OCM using a mass balance approach -- and refer to it as OCMMB. To calculate OCMMB, we subtract the other estimated retained species (including EC) from the PM2.5 level measured at the FRM site as follows:

The value for OCMMB could be very small, or even be calculated as negative (if the sum of the species enclosed in the curly brackets exceeded the FRM PM2.5 monitor value). To ensure that the OCMMB does not get too small, an OCMMB "mass balance floor" (default) value is set to 1.0 times the interpolated value of blank-adjusted organic carbon (OCb). It is also possible that the value of the floor by itself could exceed the FRM total PM2.5 value. In this case, MATS imposes a (user-adjustable) "ceiling," such that OCMMB does not exceed a percentage of the total non-blank mass. The default ceiling value is set to 0.8 or 80% of PM2.5 mass. (You can modify the floor and ceiling assumptions in the Species Fractions Calculation Options - Advancedwindow.) To account for these possibilities, MATS uses the following series of equations to calculate OCMMB:Annual PM Analysis: Details

April 2014 Abt Associates Inc. 94 

### where the " Floor " variable has a default value in MATS of "1.0" and the " Ceiling " variable has a default value in MATS of "0.8". There are at least two things to note with this approach. (1) When the final OCMMB value is equal to the "floor," then the sum of the species will exceed the PM2.5 value at the FRM monitor. To ensure that the sum of the species just equals the FRM PM2.5 value, MATS reduces all of the species (except OCMMB) by the same percentage until the sum of the species just equals the FRM PM2.5 value. (2) When the final OCMMB value is equal to the "ceiling," then the sum of the species will be less than the PM2.5 value at the FRM monitor. In that case, MATS increases all of the species by the same percentage until the sum of the species just equals the FRM PM2.5 value
Blank Mass Assumption 

### The field blank typically has a value of between 0.3 and 0.5 ug/m3, which appears to result from contamination of the FRM filter. For calculating retained PM2.5, MATS uses a default blank mass value of 0.5 ug/m3. If desired, you can change the default blank mass value at the Species Fractions Calculations Options - Advancedwindow.
5.1.2.3 Step 3: Forecasted Quarterly Average Species Calculation To calculate forecasted quarterly species averages for each of the four quarters in a given year, MATS uses weighted average quarterly species concentrations and both baseline and forecasted (e.g., 2020) air quality modeling. Because this calculation involves modeling data from two different years, this is referred to as a "temporal adjustment." The forecasted weighted quarterly average for each species is calculated by multiplying the baseline weighted quarterly average for each monitor species with the ratio of the modeling data. This process gives forecasted weighted quarterly averages of six species: SO4, NO3, OCM, EC, crustal material, and NH4. The form of the equation is as follows:Annual PM Analysis: Details

April 2014 Abt Associates Inc. 95 

### In other words, baseline species concentrations are assumed to change in the same proportion as the model data in the same location from the baseline to the forecasted. These proportions, called relative response factors (RRF), are simply the ratio of the modeled forecasted species to the modeled baseline species.

MATS calculates RRFs for each quarter for each of six species: SO4, NO3, OCM, EC, crustal material, and (optionally) NH4. (Additional information on the calculation of the RRFs can be found here .) The calculation of forecasted weighted quarterly average species concentrations can be rewritten as:

Additional calculations are needed to estimate future-year quarterly averages of NH4 and particle-bound water (PBW), which is calculated using forecasted levels of NH4, NO3, and SO4. (Details on the PBW calculation can be found here .) Recall that the default base year NH4 calculation is as follows:

MATS can calculate the future year NH4 concentration using modeled NH4 RRFs, or by using the the base year DON value combined with future year SO4 and NO3 values (default approach) as follows:

The option for choosing which approach to use for calculating future NH4 is given in the PM2.5 Calculation Optionswindow. Finally, note that PBW is calculated after future year NH4, using the previously identified water equation and future year concentrations of NH4, SO4, and NO3. Example Calculation Forecasted Species ConcentrationsAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 96 

### MATS multiplies the baseline species concentrations: Quarter SO4 NO3 OCMMB EC PBW NH4 Crustal Q1 2.3623 1.0989 3.3184 0.1993 1.0403 1.1990 0.6992 Q2 2.8991 0.7993 3.4939 0.5992 1.2039 1.3996 0.5992 Q3 1.7989 0.6997 7.0613 0.2990 1.2047 1.1997 0.2990 Q4 2.5999 1.3997 2.7773 0.3991 1.1025 1.1992 0.5996 

### with the RRFs for each quarter and species: Quarter SO4 NO3 OCMMB EC PBW NH4 Crustal Q1 0.9737 0.9873 0.9636 0.9872

-- 0.9634 0.9808 Q2 0.9898 0.9991 0.9979 0.9917

-- 0.9697 0.9891 Q3 0.9784 0.9775 0.9875 0.9944

-- 0.9702 0.9759 Q4 0.9700 0.9800 0.9761 0.9843

-- 0.9790 0.9818 

### The product is the forecasted species concentrations by quarter. Quarter SO4 NO3 OCMMB EC PBW NH4 Crustal Q1 2.3003 1.0849 3.1975 0.1968

-- 1.1552 0.6858 Q2 2.8695 0.7985 3.4865 0.5942

-- 1.3571 0.5927 Q3 1.7600 0.6840 6.9728 0.2973

-- 1.1640 0.2918 Q4 2.5219 1.3717 2.7109 0.3928

-- 1.1741 0.5887



### 5.1.2.4 Step 4: Forecasted Design Value Calculation The forecasted weighted quarterly averages for the species are then added together to get the estimated forecasted quarterly average PM2.5 level:

MATS averages the four quarterly averages these forecasted quarterly average PM2.5 levels to calculate forecasted design values:

The output file containing the results of this Standard Analysis are described here

. Example Calculation Forecasted Design Values Using hypothetical data from the previous example calculation plus PBW values andAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 97 

### assumed blank mass, MATS sums the species to get quarterly PM2.5 values. Quarter SO4 NO3 OCMMB EC PBW NH4 Crustal Blank

Mass PM2.5 Q1 2.3003 1.0849 3.1975 0.1968 0.5000 1.1552 0.6858 0.5000 9.6205 Q2 2.8695 0.7985 3.4865 0.5942 0.4000 1.3571 0.5927 0.5000 10.5985 Q3 1.7600 0.6840 6.9728 0.2973 0.6000 1.1640 0.2918 0.5000 12.2699 Q4 2.5219 1.3717 2.7109 0.3928 0.7000 1.1741 0.5887 0.5000 9.9601 

### MATS then averages the four quarters to get a forecasted design value: Quarter PM2.5 Q1 9.6205 Q2 10.5985 Q3 12.2699 Q4 9.9601 Forecasted Design Value 10.61



### 5.1.2.5 Output Description The output file is named "Annual PM25 Point.csv " with the Scenario Nameappended at the beginning and the forecast year is inserted at the end (e.g., " Example PM -- Annual PM25 Point 2020.csv "). The table below describes the variables in the output file for the Standard Analysis. Note: The RRF variables in this file are not the actual RRFs used to calculate future year PM2.5 and PM2.5 species. They are the resultant annual average RRFs calculated by dividing the future annual average concentrations (in this file) by the base year annual average concentrations (in this file). The actual RRFs are calculated on a quarterly average basis and are contained in the quarterly average output files. There are no quarterly average RRFs for water or NH4 (if DON, NO3, and SO4 are used to calculate NH4). Output file name: "Scenario Name + Annual PM25 Point" Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _type FRM data _STATE_NAME State name. (This is a character variable.) _COUNTY_NAM E County name. (This is a character variable.) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 98 monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_gridcell Identifier of grid cell closest to the monitor b_pm25_ann_DV Base year 5 year weighted average PM2.5 annual design value f_pm25_ann_DV Future year 5 year weighted average PM2.5 annual design value b_blank_mass Base year blank mass concentration (ug/m3) b_crustal_mass Base year crustal mass concentration (ug/m3) b_EC_mass Base year elemental carbon mass concentration (ug/m3) b_NH4_mass Base year ammonium mass concentration (ug/m3) b_Ocmb_mass Base year organic carbon mass (by difference) concentration (ug/m3) b_SO4_mass Base year sulfate ion mass concentration (ug/m3) b_NO3_mass Base year nitrate ion mass concentration (ug/m3) b_water_mass Base year water mass concentration (ug/m3) b_salt_mass Base year salt mass concentration (ug/m3) f_blank_mass Future year blank mass concentration (ug/m3) f_crustal_mass Future year crustal mass concentration (ug/m3) f_EC_mass Future year elemental carbon mass concentration (ug/m3) f_NH4_mass Future year ammonium mass concentration (ug/m3) f_Ocmb_mass Future year organic carbon mass (by difference) concentration (ug/m3) f_SO4_mass Future year sulfate ion mass concentration (ug/m3) f_NO3_mass Future year nitrate ion mass concentration (ug/m3) f_water_mass Future year water mass concentration (ug/m3) f_salt_mass Future year salt mass concentration (ug/m3) rrf_crustal Resultant annual relative response factor- Crustal Mass rrf_ec Resultant annual response factor- Elemental Carbon Mass rrf_nh4 Resultant annual relative response factor- Ammonium Mass. rrf_oc Resultant annual relative response factor- Organic Carbon Mass rrf_so4 Resultant annual relative response factor- Sulfate Mass rrf_no3 Resultant annual relative response factor- Nitrate Mass rrf_water_mass Resultant annual relative response factor- Water Mass rrf_salt Resultant annual relative response factor- Salt Mass (set equal to 1 if modeled salt is not used) 

## 5.1.3 Quarterly Model Data The Quarterly Model Dataoption gives you the option of creating a small, reusable file with quarterly values from a much larger file with daily values. Since annual PM2.5 MATS works with quarterly values there is no loss of precision. To save time, it is possible to use daily values only for an initial run with MATS and check this QuarterlyAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 99 

### Model Dataoption. Then for subsequent runs (that use the same modeled data), use the quarterly file that MATS generates. However, this will only work for subsequent MATS runs that use exactly the same base and future year photochemical model data (such as sensitivity runs that test the various ambient data settings in MATS). Alternatively, you can generate a baseline and future quarterly average model file outside of MATS (using a program such as SAS, STATA, etc), and then load these quarterly files into MATS, bypassing the use of any daily model data in MATS. The format of the quarterly file is described below. MATS generates two files:

· Base-year file: " Baseline Quarterly Avg Model Data.csv " with the Scenario Name (e.g., Example PM Annual) appended at the beginning (e.g., " Example PM Annual -- Baseline Quarterly Avg Model Data.csv ").

· Future year file (e.g., " Example PM -- FutureQuarterly Avg Model Data.csv ." The format of the two files is the same. The table below describes the variables in the Quarterly Model Datafile. Output file name: "Scenario Name + Baseline/Future Quarterly Avg Model Data" Variable Description _id The ID is a unique identifier for each model grid cell. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) _type lat Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. long Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. date Year and Quarter (01= 1st quarter, 04= 2nd quarter, etc.) crustal Crustal PM nh4 Ammonium PM so4 Sulfate PM
ec Elemental Carbon no3 Nitrate PM

oc Organic carbon PM pm25 PM2.5 mass (only used to gradient adjust PM2.5 for gradient adjusted spatial fields) cm Coarse PM (ug/m3) (only used for visbility calculations)



### MATS also produces a set of "used" quarterly average model day files (base and future). These have the same format as the quarterly average model data files, but only contain dataAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 100 

### for the model grid cells that were used in the MATS point calculations. These files can also be re-used and are also useful for QA purposes. The table below describes the variables in the Used Quarterly Model Datafile: Output file name: "Scenario Name + Used Baseline/Future Quarterly Avg Model Data" Variable Description _id The ID is a unique identifier for each model grid cell. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) _type lat Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. long Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. date Year and Quarter (01= 1st quarter, 04= 2nd quarter, etc.) crustal Crustal PM nh4 Ammonium PM so4 Sulfate PM
ec Elemental Carbon no3 Nitrate PM

oc Organic carbon PM pm25 PM2.5 mass (only used to gradient adjust PM2.5 for gradient adjusted spatial fields) cm Coarse PM (ug/m3) (only used for visbility calculations)



## 5.1.4 Species Fractions Species fractions are simply the fraction of quarterly average PM2.5 at a given monitor attributable to seven (and potentially eight) species: nitrate (NO3), sulfate (SO4), organic carbon (OC), crustal, elemental carbon (EC), ammonium (NH4), and particle-bound water (PBW). (And pending data availability, an eighth species, salt, can be included as well; the default MATS species files include salt data. But salt is an optional species on the model files. If base and future year modeled salt data is supplied, a salt RRF will be calculated. If there is no salt data in the model files, then the salt RRF will be set to 1.) When you check the Species Fractions option, you get a reusablefile with species fractions for each FRM monitor. Making the file reusable allows you to generate consistent results and, perhaps most importantly, allows the same file to be used by different MATS users.
5.1.4.1 Species Fractions Calculation After calculating the ambient level of SO4, NO3, OCMMB, EC, PBW, NH4, and crustal, MATS then divides these ambient levels by the non-blank mass of PM2.5. To get non-Annual PM Analysis: Details

April 2014 Abt Associates Inc. 101 

### blank PM2.5, MATS subtracts the blank mass from the FRM PM2.5 value. MATS then divides each of the species (except blank mass) by non-blank PM2.5. Example Calculation of Species Fractions The table below gives an example of theses calculations. The fraction is calculated by dividing mass (ug/m3) by the Non-blank Mass. Note that salt is optional.
Units FRM PM2.5 Blank Mass Non-Bla nk Mass SO4 NO3 OCMM B EC PBW NH4 Crusta l (Salt)

Concentrati on 10.9175 0.5 10.4175 2.4160 1.1555 3.4847 0.2101 1.1555 1.2605 0.7353

-- Fraction 0.2319 0.1109 0.3345 0.0202 0.1109 0.1210 0.0706

--



### 5.1.4.2 Output Description The output file is named " Quarterly Avg Spec Frac Point.csv " with the Scenario Name appended at the beginning (e.g., " Example PM -- Quarterly Avg Spec Frac Point.csv "). The table below describes the variables in the file. The interpolated variables (starting with i_xxx) are created when MATS is run, but are not needed when re-using a fractions file. They are also not needed when running with a user generated fractions file. Output file name: "Scenario Name + Quarterly Avg Spec Frac Point" Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _STATE_NAME State name. (This is a character variable.) _COUNTY_NAME County name. (This is a character variable.) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. quarter Quarter pm25_mass_frac PM2.5 mass used to calculate species fractions (calculated from the "PM2.5 for fractions" file) fcr Crustal fraction of PM2.5 mass fec Elemental carbon fraction of PM2.5 mass fnh4 Ammonium fraction of PM2.5 mass focm Organic carbon fraction of PM2.5 mass fso4 Sulfate ion fraction of PM2.5 mass fno3 Nitrate ion fraction of PM2.5 mass fwater Water fraction of PM2.5 mass fsalt Salt fraction of PM2.5 massAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 102 blank_mass Blank mass don Degree of neutralization of sulfate used to calculate ammonium mass (0.000 - 0.375) i_so4 Interpolated sulfate ion i_no3r Interpolated retained nitrate ion i_ocb Interpolated blank-adjusted organic carbon i_ec Interpolated elemental carbon i_crustal Interpolated crustal i_don Interpolated degree of neutralization of sulfate (DON). i_nh4 Interpolated ammonium i_no3 Interpolated nitrate ion (only used to calculate volatilized ammonium; if option is selected) i_salt Interpolated salt



### Notes : i_ocb is only used to to calculate the OCMmb "floor". i_nh4 is not used if DON is used to calculate the ammonium concentration (and fraction). i_no3 is only used to calculate the "volatilized ammonium", if the option is selected (not used by default). 

## 5.2 Output Choice - Advanced
In the Output Choice Advancedwindow, MATS lets you choose from among two main options: Spatial Field Estimatesand Miscellaneous Output that is generally used for quality assurance (QA). Within each of these two main options there are a number of choices.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 103 

## Spatial Field Estimates . This option gives you PM2.5 forecasts for each grid cell in the modeling domain (e.g., CMAQ 36 km).

· The Interpolate FRM & speciation monitor data to spatial field. Temporally-adjust option calculates interpolated spatial fields that are temporally adjusted. This option creates gridded spatial fields of future year PM2.5 data. To create PM2.5 spatial fields, MATS interpolates both speciation data andPM2.5 data (FRM and IMPROVE).

· The Interpolate gradient-adjusted FRM & speciation monitor data to spatial field. Temporally-adjustoption calculates interpolated spatial fields that are temporally adjusted and gradient adjusted. Check this option to create gridded spatial fields of gradient adjusted future year PM2.5 data. To create PM2.5 spatial fields, MATS interpolates both gradient adjusted speciation data andPM2.5 data (FRM and IMPROVE). This option creates the recommended spatial field for the “Unmonitored Area Analysis” from the PM2.5 modeling guidance. 

## Miscellaneous Output . This provides a variety of output files that can be used to QA the your calculations.

· Quarterly average files

. The MATS default is to output the annual average results for all analyses (point, spatial fields). Checking any one of these boxes will also output the more detailed quarterly average calculations (the quarterly average calculations are the basis of all of the MATS annual PM2.5 calculations).

· High county sites

. The MATS default is to output the point results for all FRM sites. Checking this box will also create a file which contains only the single highest monitor in each County (based on the highest future year value). This dataset is a subset of the all sites file.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 104 

### · Species fractions spatial field

. This option is the same as the species fraction file created from the standard analysis except it outputs the species fractions file created from a spatial field. The file will contain species fraction data for each quarter for each grid cell.

· Quarterly average speciated monitors

. This file contains the raw quarterly average speciated data that MATS uses to do interpolations (to calculate species fractions). This data is derived from the “species for fractions” input file.

· Design Value Periods. This file contains standard MATS output for each design period within the period covered by the analysis.

· Neighbor files

. The neighbor files contain the “nearest neighbor” data for the VNA interpolation scheme. The data includes the distance to neighbor monitors and weights used to do the interpolations. There is information for each FRM monitor (for point analyses) or each grid cell (for spatial fields) for each quarter and for each species.


## 5.2.1 Spatial Field Estimates With the Spatial Field Estimates optionyou can estimate PM2.5 for each grid cell in a spatial field by interpolating both FRM monitor data and speciated monitor data to the grid cell centroid (identified by latitude and longitude). A keydifference between Spatial Field Estimates and Standard Analysisis that the Spatial Field Estimates requires the interpolation of FRM monitor data. MATS interpolates the "unofficial" daily PM2.5 monitor data from FRM and IMPROVE sites to each grid cell centroid and then averages the values for each quarter from the different PM2.5 sites. (Recall, as discussed in the Baseline PM2.5 Calculationsection, the Standard Analysis uses "official" PM2.5 monitor data.) The basic form of the spatial calculation is as follows:

Gridcell E, baseline 

### = estimated quarterly average baseline species concentration at grid cell E; Weighti 

### = inverse distance weight for monitor i;
Monitori 

### = quarterly average baseline species concentration at monitor i. Note that MATS lets you choose whether to use air quality modeling to scale the interpolation of speciated monitor values to grid cell centroids (spatial fields). This use of modeling data is referred to as a gradient adjustment, and is discussed in the next section

. 5.2.1.1 Gradient-Adjustment- ("Fused fields") Using modeling data for a gradient adjustmentis fairly simple. MATS calculates species fractions using monitor data in basically the same way as in the species fractionsAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 105 

### calculation for the Standard Analysis , however, MATS includes model data to help inform the calculation. In particular, MATS uses model values for the grid cell of interest and the model values for the grid cells containing the speciated/PM2.5 monitors to be interpolated to cell of interest. (Note that "unofficial" PM2.5 values are used in the interpolation, and they are treated in essentially the same way as monitor data for particular species, such as SO4.) A general form of the equation for the interpolated species values is as follows:

where: Species E, baseline 

### = estimated baseline quarterly average species/PM2.5 concentration at cell E; Weighti 

### = inverse distance weight for monitor i;
Monitori 

### = baseline quarterly average species/PM2.5 concentration at monitor i; Gradient Adjustmenti, E

### = gradient adjustment from monitor i to cell E. This interpolation calculation can be rewritten somewhat more precisely as:

where: Model E, baseline 

### = modeled quarterly average baseline species/PM2.5 concentration at cell E;


### Model i, baseline 

### = modeled quarterly average baseline species/PM2.5 concentration at monitor site i.



### MATS uses this gradient approach for PM2.5 and for most species -- SO4, NO3r, EC, OCb, Crustal, and NH4. However, for DON (degree of neutralization), MATS does not use a gradient adjustment and simply interpolates the estimated DON values as is from each monitor. Options regarding the use of model data are discussed in more detail in the section on Model Data Options

. Once MATS has interpolated quarterly species values at the cell of interest, calculations proceed in exactly the same way as described for species fractions and forecasted PM2.5 values for the Standard Analysis.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 106 

### Example Calculation for Interpolated Gradient-Adjusted Baseline Species Concentrations For each quarter, MATS identifies the speciated monitors that are nearby ("neighbors") to a given cell of interest "E", and determines the weight that should be given to each monitor in the interpolation process. Monitors that are nearby get a greater weight. Speciated Monitor Values Monitor ID Quarter SO4 NO3r EC OCb Crustal NH4 DON Interpolation

Wght A Q1 2.30 1.10 3.32 0.20 1.10 1.20 0.21 0.2 B Q1 2.90 0.80 3.49 0.60 1.20 1.40 0.19 0.4 C Q1 1.80 0.70 7.06 0.30 1.20 1.20 0.18 0.15 D Q1 2.60 1.40 2.78 0.40 1.10 1.20 0.32 0.25 

### MATS then identifies the speciated model values at each of the speciated monitors (A-D) and for the given cell of interest (E): Model Values at Speciated Monitor Sites A-D Monitor ID Quarter SO4 NO3 EC OC Crustal NH4 DON A Q1 1.60 1.03 2.99 0.15 0.75 0.86

-- B Q1 2.54 0.70 3.20 0.47 1.07 1.04

-- C Q1 1.66 0.59 5.91 0.23 1.13 0.81

-- D Q1 1.93 1.15 2.13 0.27 1.00 1.12

--
Model Values at Cell E Monitor ID Quarter SO4 NO3 EC OC Crustal NH4 DON E Q1 2.10 0.98 3.10 0.15 1.00 1.30

-- 

### MATS then calculates the speciated values at cell E using the monitor and model data (and interpolation weights) using the equation above: Interpolated Speciated Monitor Values Monitor ID Quarter SO4 NO3r EC OCb Crustal NH4 DON A Q1 3.02 1.04 3.44 0.20 1.46 1.82 0.21 B Q1 2.40 1.12 3.38 0.19 1.13 1.75 0.19 C Q1 2.27 1.16 3.71 0.19 1.06 1.93 0.18 D Q1 2.83 1.19 4.05 0.22 1.10 1.39 0.32 Wght. Avg. Q1 2.61 1.13 3.61 0.20 1.18 1.70 0.23 

### Note that MATS does a similar calculation (not shown) when interpolating "unofficial" PM2.5 values to the given cell of interest, denoted "E".
5.2.1.2 Output Description - Interpolate FRM & Speciation Monitor Data to Spatial Field The output file is named "Annual PM25 Spatial Field " with the Scenario NameappendedAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 107 

### at the beginning and the forecast year is inserted at the end (e.g., " Example PM -- Annual PM25 Spatial Field 2020.csv "). The table below describes the variables in the output file. Output file name: "Scenario Name + Annual PM25 Spatial Field" Variable Description _id The ID is a unique identifier for each model grid cell. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) gridcell_lat Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. gridcell_long Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. b_pm25_ann_DV Base year interpolated PM2.5 from unofficial data file f_pm25_ann_DV Future year interpolated PM2.5 b_blank_mass Base year blank mass concentration (ug/m3) b_crustal_mass Base year crustal mass concentration (ug/m3) b_EC_mass Base year elemental carbon mass concentration (ug/m3) b_NH4_mass Base year ammonium mass concentration (ug/m3) b_Ocmb_mass Base year organic carbon mass (by difference) concentration (ug/m3) b_SO4_mass Base year sulfate ion mass concentration (ug/m3) b_NO3_mass Base year nitrate ion mass concentration (ug/m3) b_water_mass Base year water mass concentration (ug/m3) b_salt_mass Base year salt mass concentration (ug/m3) f_blank_mass Future year blank mass concentration (ug/m3) f_crustal_mass Future year crustal mass concentration (ug/m3) f_EC_mass Future year elemental carbon mass concentration (ug/m3) f_NH4_mass Future year ammonium mass concentration (ug/m3) f_Ocmb_mass Future year organic carbon mass (by difference) concentration (ug/m3) f_SO4_mass Future year sulfate ion mass concentration (ug/m3) f_NO3_mass Future year nitrate ion mass concentration (ug/m3) f_water_mass Future year water mass concentration (ug/m3) f_salt_mass Future year salt mass concentration (ug/m3) rrf_crustal Resultant annual relative response factor- Crustal Mass rrf_ec Resultant annual response factor- Elemental Carbon Mass rrf_nh4 Resultant annual relative response factor- Ammonium Mass. rrf_oc Resultant annual relative response factor- Organic Carbon Mass rrf_so4 Resultant annual relative response factor- Sulfate Mass rrf_no3 Resultant annual relative response factor- Nitrate Mass rrf_water_mass Resultant annual relative response factor- Water Mass rrf_salt Resultant annual relative response factor- Salt MassAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 108 

### 5.2.1.3 Output Description - Interpolate Gradient-Adjusted FRM & Speciation Monitor Data to Spatial Field The output file is named " Grad Adj Annual PM25 Spatial Field " with the Scenario Name appended at the beginning and the forecast year is inserted at the end (e.g., " Example PM

-- Grad Adj Annual PM25 Spatial Field 2020.csv "). The table below describes the variables in the output file. Output file name: "Scenario Name + Grad Adj Annual PM25 Spatial Field" Variable Description _id The ID is a unique identifier for each model grid cell. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) gridcell_lat Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. gridcell_long Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. b_pm25_ann_DV_ga Base year gradient adjusted interpolated PM2.5 from unofficial data file f_pm25_ann_DV_ga Future year gradient adjusted interpolated PM2.5 b_blank_mass_ga Base year blank mass concentration (ug/m3) b_crustal_mass_ga Base year crustal mass concentration (ug/m3) b_EC_mass_ga Base year elemental carbon mass concentration (ug/m3) b_NH4_mass_ga Base year ammonium mass concentration (ug/m3) b_Ocmb_mass_ga Base year organic carbon mass (by difference) concentration (ug/m3) b_SO4_mass_ga Base year sulfate ion mass concentration (ug/m3) b_NO3_mass_ga Base year nitrate ion mass concentration (ug/m3) b_water_mass_ga Base year water mass concentration (ug/m3) b_salt_mass_ga Base year salt mass concentration (ug/m3) f_blank_mass_ga Future year blank mass concentration (ug/m3) f_crustal_mass_ga Future year crustal mass concentration (ug/m3) f_EC_mass_ga Future year elemental carbon mass concentration (ug/m3) f_NH4_mass_ga Future year ammonium mass concentration (ug/m3) f_Ocmb_mass_ga Future year organic carbon mass (by difference) concentration (ug/m3) f_SO4_mass_ga Future year sulfate ion mass concentration (ug/m3) f_NO3_mass_ga Future year nitrate ion mass concentration (ug/m3) f_water_mass_ga Future year water mass concentration (ug/m3) f_salt_mass_ga Future year salt mass concentration (ug/m3) rrf_crustal Resultant annual relative response factor- Crustal Mass rrf_ec Resultant annual response factor- Elemental Carbon Mass rrf_nh4 Resultant annual relative response factor- Ammonium Mass. rrf_oc Resultant annual relative response factor- Organic Carbon MassAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 109 rrf_so4 Resultant annual relative response factor- Sulfate Mass rrf_no3 Resultant annual relative response factor- Nitrate Mass rrf_water_mass Resultant annual relative response factor- Water Mass rrf_salt Resultant annual relative response factor- Salt Mass


## 5.2.2 Miscellaneous Output MATS gives you ability to generate a number of specialized files for quality assurance, identify the monitor in each county with the highest forecast, and other reasons. These files include:

· Quarterly Average Files . Contain baseline PM2.5 and species concentrations, RRFs, forecasted PM2.5 and species concentrations. Available for point estimates and spatial fields, as well as gradient-adjusted spatial fields. These files are important because all of the basic PM2.5 calculations in MATS occur on a quarterly average basis. The "true" RRFs and PM2.5 and species concentrations are found in the quarterly average files.

· High County Sites . Monitor chosen in county based on highest future-year value. Contains baseline PM2.5 and species concentrations, RRFs, forecasted PM2.5 and species. File only available for the Standard Analysis (point) results.

· Species Fractions for Spatial Fields . Contains quarterly species fractions and interpolated species values for spatial fields.

· Quarterly Average Speciated Monitors . Contains baseline quarterly average monitored species concentrations at STN and IMPROVE sites. This is the subset of species data that MATS uses for each particular scenario (based on the MATS inputs and configuration settings).

· Design Value Periods. This file contains standard MATS output for each design period within the period covered by the analysis.

· Neighbor Files . Contains neighbor identifiers for interpolation to both FRM sites or to spatial fields.
5.2.2.1 Quarterly Average Files The Quarterly Average Files provide intermediate calculations performed by MATS. In particular, these files have the weighted quarterly average baseline and future values for PM2.5 and its constituent species. In addition it gives the speciated RRFs. There are potentially three Quarterly Average Files: one for Point Estimates and two for Spatial Field Estimates (with and without gradient adjustment). Output Description - Quarterly Average Point 

### The output file is named " Quarterly PM25 Point " with the Scenario Nameappended at the beginning (e.g., " Example Annual PM -- Quarterly PM25 Point.csv "). The tableAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 110 

### below describes the variables in the output file. Output file name: "Scenario Name + Quarterly PM25 Point + Year" Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _type FRM data _state_name State name. (This is a character variable.) _county_name County name. (This is a character variable.) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_gridcell Identifier of grid cell closest to the monitor quarter Quarter b_pm25_ann_q_DV Base year 5 year weighted average PM2.5 (quarter) design value f_pm25_ann_q_DV Future year 5 year weighted average PM2.5 (quarter) design value b_blank_mass_q Base year blank mass concentration (ug/m3) b_crustal_mass_q Base year crustal mass concentration (ug/m3) b_EC_mass_q Base year elemental carbon mass concentration (ug/m3) b_NH4_mass_q Base year ammonium mass concentration (ug/m3) b_Ocmb_mass_q Base year organic carbon mass (by difference) concentration (ug/m3) b_SO4_mass_q Base year sulfate ion mass concentration (ug/m3) b_NO3_mass_q Base year nitrate ion mass concentration (ug/m3) b_water_mass_q Base year water mass concentration (ug/m3) f_blank_mass_q Future year blank mass concentration (ug/m3) f_crustal_mass_q Future year crustal mass concentration (ug/m3) f_EC_mass_q Future year elemental carbon mass concentration (ug/m3) f_NH4_mass_q Future year ammonium mass concentration (ug/m3) f_Ocmb_mass_q Future year organic carbon mass (by difference) concentration (ug/m3) f_SO4_mass_q Future year sulfate ion mass concentration (ug/m3) f_NO3_mass_q Future year nitrate ion mass concentration (ug/m3) f_water_mass_q Future year water mass concentration (ug/m3) rrf_crustal Relative response factor- Crustal Mass rrf_ec Relative response factor- Elemental Carbon Mass rrf_nh4 Relative response factor- Ammonium Mass. (Only calculated if ammonium in model data and measured ammonium ["NH4"] used in calculations.) rrf_oc Relative response factor- Organic Carbon Mass rrf_so4 Relative response factor- Sulfate Mass rrf_no3 Relative response factor- Nitrate MassAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 111 Output Description - Quarterly Average Spatial Field 

### The output file is named " Quarterly PM25 Spatial Field " with the Scenario Name appended at the beginning (e.g., " Example Annual PM -- Quarterly PM25 Spatial Field

. csv "). The table below describes the variables in the output file. Output file name: "Scenario Name + Quarterly PM25 Spatial Field + Year" Variable Description _id The ID is a unique identifier for each model grid cell. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) gridcell_lat Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. gridcell_long Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. quarter Quarter b_pm25_ann_q_DV Base year 5 year weighted average PM2.5 (quarter) design value f_pm25_ann_q_DV Future year 5 year weighted average PM2.5 (quarter) design value b_blank_mass_q Base year blank mass concentration (ug/m3) b_crustal_mass_q Base year crustal mass concentration (ug/m3) b_EC_mass_q Base year elemental carbon mass concentration (ug/m3) b_NH4_mass_q Base year ammonium mass concentration (ug/m3) b_Ocmb_mass_q Base year organic carbon mass (by difference) concentration (ug/m3) b_SO4_mass_q Base year sulfate ion mass concentration (ug/m3) b_NO3_mass_q Base year nitrate ion mass concentration (ug/m3) b_water_mass_q Base year water mass concentration (ug/m3) f_blank_mass_q Future year blank mass concentration (ug/m3) f_crustal_mass_q Future year crustal mass concentration (ug/m3) f_EC_mass_q Future year elemental carbon mass concentration (ug/m3) f_NH4_mass_q Future year ammonium mass concentration (ug/m3) f_Ocmb_mass_q Future year organic carbon mass (by difference) concentration (ug/m3) f_SO4_mass_q Future year sulfate ion mass concentration (ug/m3) f_NO3_mass_q Future year nitrate ion mass concentration (ug/m3) f_water_mass_q Future year water mass concentration (ug/m3) rrf_crustal Relative response factor- Crustal Mass rrf_ec Relative response factor- Elemental Carbon Mass rrf_nh4 Relative response factor- Ammonium Mass. (Only calculated if ammonium in model data and measured ammonium ["NH4"] used in calculations.) rrf_oc Relative response factor- Organic Carbon Mass rrf_so4 Relative response factor- Sulfate Mass rrf_no3 Relative response factor- Nitrate MassAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 112 Output Description - Quarterly Average Spatial Field - Gradient Adjusted 

### The output file is named " Grad Adj Quarterly PM25 Spatial Field " with the Scenario Nameappended at the beginning (e.g., " Example Annual PM -- Grad Adj Quarterly PM25 Spatial Field.csv "). The table below describes the variables in the output file. Output file name: "Scenario Name + Grad Adj Quarterly PM25 Spatial Field + Year" Variable Description _id The ID is a unique identifier for each model grid cell. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) gridcell_lat Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. gridcell_long Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. quarter Quarter b_pm25_ann_q_DV_ga Base year 5 year weighted average PM2.5 (quarter) design value f_pm25_ann_q_DV_ga Future year 5 year weighted average PM2.5 (quarter) design value b_blank_mass_q_ga Base year blank mass concentration (ug/m3) b_crustal_mass_q_ga Base year crustal mass concentration (ug/m3) b_EC_mass_q_ga Base year elemental carbon mass concentration (ug/m3) b_NH4_mass_q_ga Base year ammonium mass concentration (ug/m3) b_Ocmb_mass_q_ga Base year organic carbon mass (by difference) concentration (ug/m3) b_SO4_mass_q_ga Base year sulfate ion mass concentration (ug/m3) b_NO3_mass_q_ga Base year nitrate ion mass concentration (ug/m3) b_water_mass_q_ga Base year water mass concentration (ug/m3) f_blank_mass_q_ga Future year blank mass concentration (ug/m3) f_crustal_mass_q_ga Future year crustal mass concentration (ug/m3) f_EC_mass_q_ga Future year elemental carbon mass concentration (ug/m3) f_NH4_mass_q_ga Future year ammonium mass concentration (ug/m3) f_Ocmb_mass_q_ga Future year organic carbon mass (by difference) concentration (ug/m3) f_SO4_mass_q_ga Future year sulfate ion mass concentration (ug/m3) f_NO3_mass_q_ga Future year nitrate ion mass concentration (ug/m3) f_water_mass_q_ga Future year water mass concentration (ug/m3) rrf_crustal_ga Relative response factor- Crustal Mass rrf_ec_ga Relative response factor- Elemental Carbon Mass rrf_nh4_ga Relative response factor- Ammonium Mass. (Only calculated if ammonium in model data and measured ammonium ["NH4"] used in calculations.) rrf_oc_ga Relative response factor- Organic Carbon Mass rrf_so4_ga Relative response factor- Sulfate Mass rrf_no3_ga Relative response factor- Nitrate MassAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 113 

### 5.2.2.2 Output Description - High County Sites In this file, MATS reports the monitor with the highest forecasted PM2.5 design value in each county. The name of this file is " High County Sites " with the Scenario Name appended at the beginning (e.g., " Example Annual PM -- High County Sites.csv "). The table below describes the variables in the output file. Output file name: "Scenario Name + High County Sites + Year" Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _type FRM data _state_name State name. (This is a character variable.) _county_name County name. (This is a character variable.) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_gridcell Identifier of grid cell closest to the monitor b_pm25_ann_DV Base year 5 year weighted average PM2.5 annual design value f_pm25_ann_DV Future year 5 year weighted average PM2.5 annual design value b_blank_mass Base year blank mass concentration (ug/m3) b_crustal_mass Base year crustal mass concentration (ug/m3) b_EC_mass Base year elemental carbon mass concentration (ug/m3) b_NH4_mass Base year ammonium mass concentration (ug/m3) b_Ocmb_mass Base year organic carbon mass (by difference) concentration (ug/m3) b_SO4_mass Base year sulfate ion mass concentration (ug/m3) b_NO3_mass Base year nitrate ion mass concentration (ug/m3) b_water_mass Base year water mass concentration (ug/m3) f_blank_mass Future year blank mass concentration (ug/m3) f_crustal_mass Future year crustal mass concentration (ug/m3) f_EC_mass Future year elemental carbon mass concentration (ug/m3) f_NH4_mass Future year ammonium mass concentration (ug/m3) f_Ocmb_mass Future year organic carbon mass (by difference) concentration (ug/m3) f_SO4_mass Future year sulfate ion mass concentration (ug/m3) f_NO3_mass Future year nitrate ion mass concentration (ug/m3) f_water_mass Future year water mass concentration (ug/m3)



### 5.2.2.3 Species Fractions Spatial Field Contains quarterly species fractions and interpolated species values (with or without gradient-adjustment) for spatial fields. (Note that you cannotcurrently load this file intoAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 114 

### MATS, and instead this file is currently only for information. A future version of MATS may allow loading in species fractions for spatial fields.) Output Description - Species Fractions Spatial Field 

### In this file, MATS reports the quarterly species fractions. The name of this file is " Quarterly Avg Spec Frac Spatial Field " with the Scenario Nameappended at the beginning (e.g., " Example Annual PM -- Quarterly Avg Spec Frac Spatial Field.csv "). The table below describes the variables in the output file. Output file name: "Scenario Name + Quarterly Avg Spec Frac Spatial Field" Variable Description _ID The ID is a unique identifier for each model grid cell. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) gridcell_lat Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. gridcell_long Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. quarter Quarter PM25_mass_frac PM2.5 mass used to calculate species fractions (calculated from the "PM2.5 for fractions" file fcr Crustal fraction of PM2.5 mass fec Elemental carbon fraction of PM2.5 mass fnh4 Ammonium fraction of PM2.5 mass focm Organic carbon fraction of PM2.5 mass fso4 Sulfate ion fraction of PM2.5 mass fno3 Nitrate ion fraction of PM2.5 mass fwater Water fraction of PM2.5 mass fsalt Salt fraction of PM2.5 mass blank_mass Blank mass don Degree of neutralization of sulfate used to calculate ammonium mass (0.000 - 0.375) i_SO4 Interpolated sulfate ion i_NO3R Interpolated nitrate ion i_OCB Interpolated blank-adjusted organic carbon i_EC Interpolated elemental carbon i_CRUSTAL Interpolated crustal i_DON Interpolated degree of neutralization of sulfate (DON). i_SALT Interpolated salt i_NH4 Interpolated ammonium
Output Description - Gradient-Adjusted Species Fractions Spatial Field 

### In this file, MATS reports the gradient adjusted quarterly species fractions. The name ofAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 115 

### this file is " Grad Adj Quarterly Avg Spec Frac Spatial Field " with the Scenario Name appended at the beginning (e.g., " Example Annual PM -- Grad Adj Quarterly Avg Spec Frac Spatial Field.csv "). The table below describes the variables in the output file. Output file name: "Scenario Name + Grad Adj Quarterly Avg Spec Frac Spatial Field" Variable Description _ID The ID is a unique identifier for each model grid cell. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) gridcell_lat Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. gridcell_long Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. quarter Quarter PM25_mass_frac_ga PM2.5 mass used to calculate species fractions (calculated from the "PM2.5 for fractions" file) fcr_ga Crustal fraction of PM2.5 mass fec_ga Elemental carbon fraction of PM2.5 mass fnh4_ga Ammonium fraction of PM2.5 mass focm_ga Organic carbon fraction of PM2.5 mass fso4_ga Sulfate ion fraction of PM2.5 mass fno3_ga Nitrate ion fraction of PM2.5 mass fwater_ga Water fraction of PM2.5 mass fsalt_ga Salt fraction of PM2.5 mass blank_mass_ga Blank mass don_ga Degree of neutralization of sulfate used to calculate ammonium mass (0.000 - 0.375) i_SO4_ga Interpolated sulfate ion i_NO3R_ga Interpolated nitrate ion i_OCB_ga Interpolated blank-adjusted organic carbon i_EC_ga Interpolated elemental carbon i_CRUSTAL_ga Interpolated crustal i_DON Interpolated degree of neutralization of sulfate (DON). Note that DON is not gradient-adjusted. i_SALT_ga Interpolated salt i_NH4_ga Interpolated ammonium



### 5.2.2.4 Output Description - Quarterly Average Speciated Monitors In this file, MATS reports the quarterly averages at the speciated monitors. The name of this file is " Quarterly Avg Speciated Monitors " with the Scenario Nameappended at the beginning (e.g., " Example Annual PM -- Quarterly Avg Speciated Monitors.csv "). The table below describes the variables in the output file. Output file name: "Scenario Name + Quarterly Avg Speciated Monitors"Annual PM Analysis: Details

April 2014 Abt Associates Inc. 116 Variable Description _id IMPROVE/STN Site Code _type _state_name State name. (This is a character variable.) _county_name County name. (This is a character variable.) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_gridcell Identifier of grid cell closest to the monitor quarter Quarter b_crustal_mass Base year crustal mass concentration (ug/m3) b_EC_mass Base year elemental carbon mass concentration (ug/m3) b_NH4_mass Base year ammonium mass concentration (ug/m3) b_Ocmb_mass Base year organic carbon mass (by difference) concentration (ug/m3) b_SO4_mass Base year sulfate ion mass concentration (ug/m3) b_NO3_mass Base year nitrate ion mass concentration (ug/m3) b_water_mass Base year water mass concentration (ug/m3)



### 5.2.2.5 Design Value Periods Normally, MATS will output one set of files covering the entire analysis period specified by the user. The outputs represent the averages of the values for each 3-year design value period. If the "Output design value periods" option is checked, MATS will produce discrete outputs for each design value period. The output files will be the same as a standard analysis, but with "Period 1", "Period 2", etc., attached at the end of the name. Please note, however, that checking this option will substantially increase the MATS run time, by up to four times.
5.2.2.6 Neighbor Files MATS calculates the nearby monitors or "neighbors" separately for each species when interpolating to points, and similarly for interpolating to spatial fields, which also involves interpolation of PM monitors.

· Neighbors for Interpolating Species to Points

.

· Neighbors for Interpolating PM2.5 & Species to Spatial Fields

. Output Description - Neighbors for Interpolating Species to Points 

### In this file, MATS reports the neighbors involved in interpolating species values (except NH4 and DON) to the FRM monitor sites. The name of this file is " Neighbor File Point " with the Scenario Nameappended at the beginning (e.g., " Example Annual PM --Annual PM Analysis: Details

April 2014 Abt Associates Inc. 117 

### Neighbor File Point.csv "). The table below describes the variables in the output file. Output file name: "Scenario Name + Neighbor File Point" Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _state_name State name. (This is a character variable.) _county_name County name. (This is a character variable.) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_gridcell Identifier of grid cell closest to the monitor quarter Quarter _neighbor IMPROVE/STN Site Code. (This is a character variable.) neighbor_gridcell Identifier of grid cell closest to the neighbor distance Distance in kilometers from FRM monitor site and IMPROVE/STN/SPECTRE neighbor. weightdistance Inverse-distance weight weightdistancesquared Inverse-distance-squared weight pollutant Pollutant (e.g., SO4). Note interpolation approach can vary by pollutant Output Description - Neighbors for Interpoatling PM & Species to Spatial Field 

### In this file, MATS reports the neighbors involved in interpolating NH4 and DON to the Spatial Field. The name of this file is " Neighbor File Spatial Field - PM" with the Scenario Nameappended at the beginning (e.g., " Example Annual PM -- Neighbor File Spatial Field - PM.csv "). The table below describes the variables in the output file. Output file name: "Scenario Name + Neighbor File Spatial Field" Variable Description _id The ID is a unique identifier for each model grid cell. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) gridcell_lat Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. gridcell_long Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. quarter Quarter _neighbor IMPROVE/STN Site Code. (This is a character variable.) neighbor_gridcell Identifier of grid cell closest to the neighbor distance Distance in kilometers from FRM monitor site and IMPROVE/STN/SPECTRE neighbor.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 118 weight Inverse-distance weight Interpolation method Inverse-distance-squared weight pollutant Pollutant (e.g., SO4). Note interpolation approach can vary by pollutant 

## 5.3 Data Input In the Data Input window, you specify the MATS input files that are used in each scenario. There are three main types of files which must be specified. These include ambient PM2.5 species data, ambient total PM2.5 data (FRM and IMPROVE), and gridded model output data (e.g. CMAQ or CAMx data). There is specific terminology that is used on the Data Input page. "Official" data refers to PM2.5 FRM data that can be used to determine official design values for compliance purposes (comparison to the NAAQS). Other datasets which may not have rigid regulatory significance are sometimes referred to as "unofficial" data. The individual input file choices are explained below.



## Species Data

. MATS needs ambient PM2.5 species data to calculate species concentrations at FRM monitoring sites and spatial fields. Users have a choice of supplying a “Species Monitor Data File” or a “Species Fractions File”.

· Species Monitor Data File . The default is to provide a species monitor data file. MATS is populated with daily average species data from STN and IMPROVE sites across the country. However, users can also provide their own ambient data file.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 119 

### MATS uses the daily average species data to calculate species fractions at each FRM monitor (or at each grid cell, in the case of spatial fields). The species fraction data is combined with the “unofficial daily average PM2.5 data” to calculate species concentrations. The default MATS species data file contains all available data. However, there is a data flag to indicate site days that are recommended to be removed from the species fractions calculations. This is not necessarily the same data flags that have been identified by State agencies. We have incorporated flagging routines that remove data that are considered to be outliers and/or incomplete data. (A description of the flags is provided in the section on Species Fractions Calculation Options .)

· Species Fraction File . Alternatively, the user can choose to use a pre-calculated species fractions file which contains quarterly species information for the FRM monitors of interest. MATS can also re-use a species fractions file (either "point" or "spatial fields") that has previously been generated by MATS. To re-use a previously created fractions file, simply supply the correct path to the file. When re-using spatial fields species fractions files, either "spatial field" or gradient adjusted spatial fields" must be selected from the drop-down box. MATS cannot use both types of spatial fields species fractions files at the same time . (The calculation of species fractions is discussed here .) 

## PM2.5 Monitor Data

. MATS uses both "official" and "unofficial" data in its calculations.

· Unofficial Daily Average PM2.5 Data File

. The “unofficial daily average PM2.5” file contains the PM2.5 data that is needed to calculate species fractions. It is used in combination with the “species monitor data file” from above. The unofficial daily average PM2.5 file is not needed if the user supplies a pre-calculated species fractions file. Similar to the species monitor data file from above, the “unofficial” PM2.5 data file contains a data flag to indicate site days that are recommended to be removed from the species fractions calculations. The flagged data is matched between the species file and the PM2.5 file so that the same site days are removed. However, the PM2.5 data file contains additional data (sites that don ’ t contain speciation measurements) and therefore has additional flagged site days. These are not the same data flags that have been identified by State agencies. We have incorporated flagging routines that remove data that are considered to be outliers and/or incomplete data. (A description of the flags is provided in the section on Species Fractions Calculation Options .) The user is free to unflag existing data or add flags as necessary and appropriate.

· Official Quarterly Average FRM Data File . The “official quarterly average file” contains all of the “official” quarterly average FRM data that has been used to calculate PM2.5 design values. It is used to calculate design values and 5 year weighted average design values as part of the attainment test.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 120 

### The default data file in MATS was created by the Air Quality Analysis Group within OAQPS. In most cases, the data should not be altered, however in some cases (e.g. sensitivity analyses) there may be a need to add or remove data.


## Model Data . The “model data” refers to gridded model output from models such as CMAQ or CAMx. The user can choose either daily model data input or quarterly model data input (which is just a quarterly average of the daily model data). Either will work for annual PM2.5. The default setting is daily average data. Recall that MATS can generate quarterly average model data (which can then be re-used in subsequent MATS runs). Model data must be selected for all MATS runs. The size of the modeling grid defines the outputs for point estimates and for spatial fields. For point estimates, MATS will output the results for all specified monitors within the domain. For spatial fields, MATS will create spatial fields that match the size of the gridded model domain. Note that you need to specify both a Baseline Fileand a Forecast File . The baseline file should be consistent with the historical monitor data that you use, and the forecast year is the future-year of interest. 

## 5.3.1 Species Data Input The species data may be in form of monitor data (specified below) that MATS then uses to calculate species fractions, or it may be in the form of species fractions directly ( specified here ). Monitor data should be in the form of a simple text file. The first row specifies the frequency of the data ( e.g ., day). The second row presents comma-separated variable names. The third row begins the data values. Below is an example of the monitor data file format and descriptions of the variables in the file. Format of Speciated Monitor DataAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 121 

### Speciated Monitor Data Variable Descriptions
Variable Description _id The ID is a unique name for each monitor in a particular location. (This is a character variable.) LAT Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. LONG Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. _TYPE STN or IMPROVE network data DATE Date of daily average ambient data with YYYYMMDD format (This is a numeric variable) SO4 Measured sulfate ion NO3R Estimated nitrate retained on FRM filter, using measured nitrate, hourly T and RH NH4 Measured NH4+ ion OCB OC blank adjusted, STN uses constant blank value per sampler type, IMPROVE uses backup filter methodology EC Measured EC CRUSTAL Using IMPROVE algorithm, Crustal, aka "Fine Soil" = 2.2 ×[Al] + 2.49 ×[Si] + 1.63 ×[Ca] + 2.42 ×[Fe] + 1.94 ×[Ti] SALT Estimated salt using Cl (Salt=1.8*Cl), where Cl is elemental chloride DON Degree of neutralization of SO4 (0-0.375) H2O_AIM Calculated water using AIM and measured SO4, adjusted NO3 and measured NH4Annual PM Analysis: Details

April 2014 Abt Associates Inc. 122 OC Measured OC NO3 Measured nitrate ion SO4_3S Sulfate value derived from S, as per IMPROVE protocol. i.e. SO4_3S = 3*S. CRUSTAL_ALT Alternative Crustal calculation using measured Si, Fe, Ca, Ti (modified formula without Al) = 3.73 ×[Si] + 1.63 ×[Ca] + 2.42 ×[Fe] + 1.94 ×[Ti] FRM_MASS FRM mass MEASURED_FM STN or IMPROVE sampler measured fine mass (Teflon filter) RCFM Reconstructed Fine Mass using IMPROVE protocol, RCFM = [Amm_Sulfate] + [Amm_Nitrate] + [OCM] + [EC] + [Fine Soil] Al Measured Al Ca Measured Ca Fe Measured Fe Ti Measured Ti Si Measured Si EPA_FLAG Flag to indicate data that EPA recommends to be removed from the species fractions calculations. 0 = valid data, 1 or greater = data that has been flagged and should be removed USER_FLAG Flag to indicate additional data that the user wants to remove from the species fractions calculations. 0 = valid data, 1 or greater = data that has been flagged and should be removed 

### Note: Some variables are supplied for QA purposes only and are either not used by MATS or are calculated internally by MATS. For example, "OC" is not used by MATS (OCb is used) and H20_AIM is calculated internally. Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.)


## 5.3.2 PM2.5 Monitor Data Input MATS uses the "unofficial" daily PM2.5 file for the calculation of all species fractions files (both point and spatial field) and in the calculation of PM2.5 levels in spatial fields. MATS uses the "official" quarterly PM2.5 file for point estimates.
5.3.2.1 Unofficial Daily PM2.5 Monitor Data Input Monitor data should be in the form of a simple text file. The first row specifies the frequency of the data ( e.g ., day). The second row presents comma-separated variable names. The third row begins the data values. Below is an example of the monitor data file format and descriptions of the variables in the file.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 123 

### Format of Unofficial PM2.5 Monitor Data

Unofficial PM2.5 Monitor Data Variable Descriptions
Variable Description _ID The ID is a unique name for each monitor in a particular location. (This is a character variable.) _TYPE FRM, IMPROVE, or other "special" data -- may include dummy sites. (This is a character variable.) LAT Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. LONG Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. DATE Date of daily average ambient data with YYYYMMDD format (This is a numeric variable) PM25 Measured PM2.5 mass (ug/m3) EPA_FLAG Flag to indicate data that EPA recommends to be removed from the species fractions calculations. 0 = valid data, 1 = data that has been flagged and should be removed USER_FLAG Flag to indicate additional data that the user wants to remove from the species fractions calculations. 0 = valid data, 1 or greater = data that has been flagged and should be removed. 

### Note: Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embeddedAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 124 

### space, such as might occur with the name of a location, then use quotes.)
5.3.2.2 Official Quarterly PM2.5 Monitor Data Input Monitor data should be in the form of a simple text file. The first row specifies the frequency of the data ( e.g ., quarter). The second row presents comma-separated variable names. The third row begins the data values. Below is an example of the monitor data file format and descriptions of the variables in the file. Format of Official Quarterly PM2.5 Monitor Data

Official Quarterly PM2.5 Monitor Data Variable Descriptions
Variable Description _ID The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _TYPE Leave blank LAT Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. LONG Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. DATE Date of quarterly average ambient data with YYYYMMDD format. The date represents the first day of each quarter. (This is a numeric variable) PM25 PM2.5 mass NDAYS Number of complete days in each quarter _SUBSTITUTION_CODE Indicates whether the design value period was determined to be complete by using substitution procedures. COMPLETION_CODE Official design value completion codes (1, 2, 3, 4, or 5). Codes are valid for the end year of each 3 year design value period. _STATE_NAME State name. (This is a character variable.)Annual PM Analysis: Details

April 2014 Abt Associates Inc. 125 _COUNTY_NAME County name. (This is a character variable.) 

### Note: Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.)


## 5.3.3 Model Data Input Model data should be in the form of a simple text file. The first row specifies the frequency of the data ( e.g ., day). The second row presents comma-separated variable names. The third row begins the data values. Below is an example of the model data file format and descriptions of the variables in the file. Note that there is both a base year and a future year model file. The format for both is the same. Note that you can load in either daily model data or quarterly model data.

Format of Model DataAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 126 

### Model Data Variable Descriptions
Variable Description _ID The ID is a unique name for each monitor in a particular location. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) _TYPE Leave blank LAT Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. LONG Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. DATE Date of daily average model value with YYYYMMDD format (This is a numeric variable) CM Coarse PM mass (ug/m3) CRUSTAL Crustal PM2.5 mass NH4 Ammonium mass SO4 Sulfate PM EC Elemental carbon NO3 Nitrate PM OC Organic mass PM PM25 PM2.5 mass SALT Salt 

### Note:

· The "PM25" mass variable is used to calculate PM2.5 model "gradients" for gradient adjusted spatial fields. It is up to the user to provide a modeled PM2.5 mass concentration using an appropriate definition of modeled PM2.5 mass.

· Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.) 

## 5.4 Species Fractions Calculation Options
The Species Fractions Calculation Optionshas two main sections. One involving speciated monitor data (e.g., STN and IMPROVE monitors) and the other total PM2.5 monitor data (FRM and IMPROVE). For each type of data you can specify the years of interest , whether you want to delete certain data , and the minimum amount of datafor a monitor to be considered "valid" (and thus included in the calculations). In the next sections, we describe each of these three options in more detail. Note that these options apply more or less in the same way for both speciated monitor data and total PM2.5 monitor data. Also note that these options are no longer relevant if you have loaded a species fractions file

.

· IMPROVE-STN Monitor Data . The speciation data from STN and IMPROVE monitors are interpolated by MATS in order to provide species data for any point in a modeling domain. The interpolated species data is used to calculate species fractions atAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 127 

### FRM monitors (point estimates) and/or species fractions at all grid cells (spatial fields). Note that you do notneed to have values for all species for a monitor to be considered valid, as each species is considered individually. However, the "EPA_Flag" variable in the default "species for fractions" file has been set so that all monitor days that do not have complete species data are not used in the calculations (flag = 1). If the user wants to use the incomplete species data, the flag can changed to "0".

· PM2.5 Monitor Data . The total PM2.5 data from FRM are used by MATS to calculate species fractions for point estimates (in conjunction with the interpolated speciation data from STN and IMPROVE monitors). The interpolated species data is used to calculate species fractions at FRM monitors (point estimates) and/or species fractions at all grid cells (spatial fields).



## 5.4.1 Monitor Data Years Using the Start Yearand End Yeardrop-down menu options, you can choose more than one year of speciated data for the calculation of species fractions. The default approach inAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 128 

### MATS is to use three years of data.

MATS handles multiple years of data by calculating averages for each species by quarter and year. MATS then averages the quarterly values across the years (e.g., average quarter 1 values of SO4 across two years to get a single "quarter 1" estimate). After completing this step, MATS will have four quarterly estimates for each species at each speciated monitor. These quarterly values are then ready to be interpolated to FRM sites or to grid cell centroids in spatial fields.


## 5.4.2 Delete Specifed Data Values The default is to delete the observations specified by EPA. (That is, these observations are excluded from a particular analysis, while they of course remain in the database.) As described in the Data Input section , valid data are given a value of "0" and observations that are deleted are given a value of "1" to "10", as follows: 0. Data is OK to use 1. Important species is missing (e.g. no3, so4, oc, etc) 2. Constructed mass < 30% total mass 3. Constructed mass > 2 times total mass 4. Fire event 5. total mass < so4 6. total mass < crustal 7. OC is outside QA criteria 8. Soil is outside QA criteria 9. Both OC and soil are outside QA criteria 10. Regional concurrence on exceptional event

There is alsoan option for the user to flag data, using the same convention of "0" for valid data and "1" to "10" for data marked for deletion. If both the EPA-specifiedand Userspecifiedflags are checked, then MATS deletes any observations that are marked for deletion by either the EPA or the user. This makes it easy for the user to flag additional data for removal from the calculations (without deleting the actual record from the ambient data file).Annual PM Analysis: Details

April 2014 Abt Associates Inc. 129 

## 5.4.3 Minimum Data Requirements There are three sets of minimum data requirements:

· Minimum number of valid days per valid quarter . This is the minimum number of site-days per valid quarter. The default is 11 days, which corresponds to > 75% completeness for monitors on a 1 in 6 day schedule. This is a minimum number of samples that is routinely used in calculations of quarterly average concentrations.

· Minimum number of valid quarters required for valid season . This is the number of years of data (within the start year and end year specified) for which we have valid quarters for a given season. The default value is 1 year. If the value is set = 2, then there will need to be 2 years of valid data from quarter1 in order for quarter one to be considered complete (and the same for the other 3 quarters).

· Minimum number of valid seasons required for valid monitor

. This is the number of valid seasons that are needed in order for a particular monitor's data to be considered valid. The default is 1 for IMPROVE-STN monitor data and the range is 1-4. For example, if the value is = 1, then a monitor's data will be used in the species fractions calculations if it has at least one valid season. If the value = 4, then the site must have all 4 seasons of valid data to be used. The default for PM2.5 depends on whether the data are used in point calculations (default = 4) or spatial field calculations (default = 1).

Example 1: Minimum Days = 11, Minimum Years = 1, Minimum Seasons = 1 Consider the default assumptions and the following data from three monitors:Annual PM Analysis: Details

April 2014 Abt Associates Inc. 130 

### With the default assumptions, MATS would then use the highlighted observations and calculate averages for each quarter at each monitor in the following way:

Note that MATS would not calculate an average in quarter 2 for Monitor 1.

Example 2: Minimum Days = 11, Minimum Years = 2, Minimum Seasons = 1 Assuming the following data from three monitors:

Assuming that a minimum of two years of data for each season, MATS would then use the highlighted observations highlighted and calculate averages for each quarter at each monitor in the following way:Annual PM Analysis: Details

April 2014 Abt Associates Inc. 131 

### Note that the requirement of 2 years, reduces to a single quarter the seasonal averages calculated for Monitors 1 and 3. If you had further required that a monitor needed, say, 4 seasons, then MATS would have only calculated averages for Monitor 2. 

## 5.5 Species Fractions Calculation Options - Advanced
The Species Fractions Calculation Options - Advancedscreen allows you to make relatively advanced choices for your analysis. Generally speaking, the default options settings are consistent with the EPA modeling guidance document. One set of options allows you to specify the interpolation weighting that you want to use and whether the interpolation involves a maximum distance or not. The second set of options involves choices regarding ammonium, blank mass, and organic carbon.



## 5.5.1 Interpolation Options for Species Fractions Calculation The Interpolation Optionspanel allows you to choose how you will interpolate , orAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 132 

### combine, the values from different monitors. One approach is to use Inverse Distance Weights . This means that the weight given to any particular monitor is inversely proportional to its distance from the point of interest. A second approach is Inverse Distance Squared Weights, which means that the weights are inversely proportional to the square of the distance. And the third approach is Equal Weighting of Monitors. The default approach for PM is Inverse Distance Squared Weights.

When interpolating monitor values, MATS allows you to identify the monitors you want to use based on their distance away from the point of interest ( e.g. , the center of a grid cell). The first step in the interpolation process is to identify the monitors that are nearby, or neighbors, for each point of interest. The next step is to determine the distance ( in kilometers ) from the nearby monitors to the point of interest. The default approach is to include all valid monitors ( i.e. , those that satisfy the three criteria in the Species Fractions Calculation Options panel), regardless of distance. If you want to limit the use of monitors based on distance, type in the distance you want to use (e.g., 100) next to the pollutant of interest.

You can also change the number using the arrows. The double arrow on the right increases the number in units of 100:

and the double arrow on the left decreases the number in units of 100. The upper arrow increases the number in single digits:Annual PM Analysis: Details

April 2014 Abt Associates Inc. 133 

### and the lower arrow reduces the number in single digits. Note that a distance of one hundred (100) kilometers means that any monitors further than 100 kilometers can no longer be used in the interpolation. If a point of interest has no monitors within the specified distance, then no value is calculated.


## 5.5.2 Miscellaneous Options The Miscellaneous Options panel lets you make choices regarding:

· Ammonium . This allows you to specify whether MATS uses degree of neutralization (DON) values to calculate ammonium (NH4) or whether it uses measured ammonium in conjunction with an assumption about the percentage of NH4 that evaporates. The default option is to use DON values. If you want to use measured ammonium, you need to click the button and choose a NH4 percentage evaporating (e.g., 50). The default is "0", which assumes that no ammonium evaporates from the FRM filters. The calculations underlying the default and alternative ammonium calculations are discussed in detail in the section on species fractions calculations

.

· Default Blank Mass . The Default Blank Mass option simply allows you to set default blank mass to the desired level. The default is 0.5. You can type desired value, or use the arrows to increase or decrease the value.

· Organic Carbon . This allows you to set the "floor" and the "ceiling" for the mass balance calculation for organic carbon. The calculations involved are discussed in detail in the section on species fractions calculations

.



## 5.5.3 Internal Precision of the Calculations All calculations in MATS are carried out with single precision. In addition, most output files by default generate outputs only up to 3 digits after the decimal. Therefore, the baseAnnual PM Analysis: Details

April 2014 Abt Associates Inc. 134 

### year DV (b_pm25_ann_q_DV) may differ slightly from the sum of the component species of the quarterly PM2.5 MATS output files. In particular, the water calculation requires additional precision in the species fractions. It is therefore recommended to have at least seven decimal digits in the species fractions. This may be accomplished by increasing precision of the species and species fractions calculations to 7 (or more) significant digits by modifying the MATS.ini file as follows: set species_calc_precision=7 and species_fraction_precision=7. Please note that the future year species always add up to the future year DV. However, increases in species fractions precision may result in very small changes in future DV due to the dependence of the future concentrations on the base year concentrations. 

## 5.6 PM2.5 Calculation Options
The PM2.5 Calculation Optionswindow allows you to specify the particular years of monitor data that you want to use from the input file you specified in the Data Input section . You can also specify the following:

· Official vs. Custom Values . You can specify whether to use "official" design values, which are generally recommended, or use "custom" design values. If you choose to use custom design values, then you specify the minimum number of days of observations each valid quarter and the minimum number of valid quarters.

· Valid FRM Monitors . You can also specify the minimum number of design values (the default is 1) and whether you want to make sure that particular design values have to be used in the calculations.

· NH4 Future Calculation . You can also specify how you want to forecast NH4 values. The default approach is to use baseline DON values, and the alternative is to use baseline NH4 and a RRF value for NH4.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 135 

## 5.6.1 PM2.5 Monitor Data Years Using the Start Yearand End Yeardrop-down menu options, you can choose more than one year of official PM monitor data for the calculation of future PM2.5 values. The default approach in MATS is to use five years of data.

MATS handles multiple years of data as described in the Baseline PM2.5 Calculation section.


## 5.6.2 Design Values MATS gives you option to choose "official" design values, which are generally recommended, or to choose "custom" design values. If you choose to use custom design values, then you need to specify the minimum number of days of observations each valid quarter and the minimum number of valid quarters.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 136 

### · Minimum days for valid quarter . This is the minimum number of site-days per valid quarter. The default is 11 days, which corresponds to > 75% completeness for monitors on a 1 in 6 day schedule. This is a minimum number of samples that is routinely used in calculations of quarterly average concentrations.

· Minimum valid quarters in design value period . This is the number of quarters for which we have data within three consecutive design value periods. The default value is 12 quarters. If the value is set = 11, then there will need to be at least 11 valid quarters (i.e., two years must have 4 valid quarters and one year must have at least 3 valid quarters.)

5.6.2.1 Completion Code Use The Completion Code is a variable in the official quarterly PM2.5 monitor datafile that MATS uses to identify valid data. As noted in the section on Official Quarterly PM2.5 Monitor Data Input , the completion code has values of: 1, 2, 3, 4, or 5; and the codes are valid for the end year of each 3 year design value period. MATS uses the Completion Code variable somewhat differently when using official design values and when using custom design values.

· When using official data, MATS will only use completion codes: 1 and 2.

· When using custom data, MATS will potentially use completion codes: 1, 2, 3, and 4 (if the user specified completion criteria are met). The following is an explanation of the official EPA completion codes: Code "1"- complete data and violates the NAAQS Code "2"- complete data that is below the NAAQS Code "3"- incomplete data and violates the NAAQS Code "4" - incomplete data that is below the NAAQS Code "5" - data that is not comparable to the NAAQS and should not be used. For example, FRM data collected at a micro-scale site cannot be compared to to the annual PM2.5 NAAQS.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 137 

## 5.6.3 Valid FRM Monitors By default, MATS assumes that there only needs to be one design value for a monitor to be considered valid. In addition, MATS assumes that no particular design value is required, so different monitors with different years of data could be used. For example, if you specify the start year and end year as 2005 and 2009 (giving potential design values of 2005-2007, 2006-2008, and 2007-2009), then one monitor could have data for, say, 2005-2007 and another monitor data for 2006-2008, and both monitors would be used.



## 5.6.4 NH4 Future Calculation As described in the section on Forecasted Species Calculation , MATS can forecast NH4 using two different approaches. The default approach is to use base year DON values.



## 5.7 Model Data Options
The Model Data Optionssection allows you to specify the Temporal Adjustment at Monitor.This option specifies how many model grid cells to use in the calculation of RRFs for point estimates and for spatial estimates. Using the drop-down menu, y ou can choose 1x1, 3x3, 5,x5, and 7x7. (The default for a 12 kilometer by 12 kilometer grid is to use a 3x3 set of grid cells. The choice of grid size is discussed in the following EPA guidance: http://www.epa.gov/scram001/guidance/guide/final-03-pm-rh-guidance.pdf

) For PM analyses, MATS calculates meanconcentrations across the grid cell array (as compared to maximum concentrations used for ozone analyses).Annual PM Analysis: Details

April 2014 Abt Associates Inc. 138 

## 5.8 Final Check
The Final Checkwindow verifies the selections that you have made.Annual PM Analysis: Details

April 2014 Abt Associates Inc. 139 

### Click the button Press here to verify your selections . If there are any errors, MATS will present a message letting you know. For example, if the path to a model file is invalid -- perhaps you misspelled the file name -- you would get the following error:

After making the necessary correction, click the button Press here to verify your selections . Then click the Finishbutton.Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 140 

## 6 

# Daily PM Analysis: Quick Start Tutorial 6
In this tutorial you will forecast daily peak PM2.5 design values at monitors in the Eastern United States. The steps in this analysis are as follows:

· Step 1. Start MATS . Start the MATS program and choose to do a Daily PM analysis.

· Step 2. Output Choice . Choose the output to generate. In this example, you will do two things: forecast daily peak PM2.5 levels at monitor locations and output a species fractions file (which you can subsequently reuse, as discussed in the Output Choice section of the Daily PM Analysis: Details chapter).

· Step 3. Output Choice - Advanced . With these advanced options, you can generate a variety of files useful for quality assurance. Simply review these options and then uncheck them all. (If you are interested, these options are described in the Output Choice - Advancedsection of the Daily PM Analysis: Details chapter.)

· Step 4. Data Input . Choose the particular years of data and monitors to use in this analysis.

· Step 5. Species Fractions Calculation Options . Specify how to generate the relative response factors (RRFs) used in the forecasts.

· Step 6. Species Fractions Calculation Options - Advanced . This window allows you to make relatively advanced choices for your analysis, such as choosing different ways to interpolate the monitor data.

· Step 7. PM2.5 Calculation Options . Among other things you can specify the particular years of monitor data that you want to use.

· Step 8. Model Data Options . Choose how to use the model data, such as determining the maximum distance the model data can be from a monitor and identifying peak model values.

· Step 9. Final Check . Verify the choices you have made.

· Step 10. Map Output . Prepare maps of your forecasts.

· Step 11. View & Export Output . Examine the data in a table format.

Each step is explained below. Additional details are provided in the section Daily PM Analysis: Details

. 

## 6.1 Step 1. Start MATS Double-click on the MATS icon on your desktop, and the following window will appear:Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 141 

### Click the Daily PM Analysisbutton on the main MATS window. This will bring up the Configuration Managementwindow.

A Configurationallows you to keep track of the choices that you make when using MATS. For example, after generating results in MATS, you can go back, change one of your choices, rerun your analysis, and then see the impact of this change without having to enter in all of your other choices. For this example, we will start with a New Configuration

. Choose Create New Configurationand click the Gobutton. This will bring up the Choose Desired Outputwindow. 

## 6.2 Step 2. Output Choice
The Choose Desired Outputwindow allows you to choose the output that you would likeDaily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 142 

### to generate. MATS allows you to conduct a Standard Analysis (i.e., forecast Point Estimates at ambient monitors), output quarterly model data, and output a species fractions file.

· In the Scenario Namebox type “ Tutorial Daily PM ”

–this will be used to keep track of where your results are stored and the variable names used in your results files.

· Standard Analysis . Leave the box checked next to "Interpolate monitor data to FRM monitor sites. Temporally-adjust." MATS will create forecasts for each monitor in the monitor file.

· Quarterly Peak Model Data . Check this option. MATS generates quarterly model files that MATS generates from daily data that you have provided. This is useful if you want to reuse model files -- the quarterly files are much smaller and MATS will run faster if it can skip the step of creating quarterly data from the daily.

· Species Fraction . Check the box next to "Output species fractions" file.

· Actions on run completion . Check the box next to " Automatically extract all selected output files" . Upon completing its calculations, MATS will extract the results into a folder with the name of your scenario. Additional details on each of these options are Output Choicesection of the Daily PM Analysis - Advancedchapter.Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 143 

### When your window looks like the window above, click Next . This will bring you to the Output Choice - Advancedwindow. 

## 6.3 Step 3. Output Choice - Advanced With the advanced options in the Output Choice - Advancedwindow, you can generate a variety of files useful for quality assurance. Simply review these options and then uncheck them all. (If you are interested, these options are all described in the Output Choice - Advancedsection of the Daily PM Analysis: Details .)

When your window looks like the window above, click Next . This will bring you to the Data Inputwindow. 

## 6.4 Step 4. Data Input
The Data Inputwindow allows you to choose the species and the PM2.5 monitor data and model data that you want to use. As discussed in more detail in the following chapter (see Standard Analysis ), MATS calculates the ratio of the base and future year model data to calculate a relative response factor ( RRF) for each PM species. MATS uses the PM2.5 monitor data and interpolated species monitor data to estimate species values at each FRM site, multiplies the species values from the monitor data with the species-specific RRFs, and then estimates a future-year design value. (Additional details on Data Input are available here .)Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 144 

### Use the default settings in the Data Inputwindow. The window should look like the following:

When your window looks like the window above, click Next . This will bring you to the Species Fractions Calculation Options window. 

## 6.5 Step 5. Species Fractions Calculation Options
TheSpecies Fractions Calculation Optionswindow has several functions related to the IMPROVE-STN (species) monitor data and the (unofficial) PM2.5 monitor data. These functions include identifying the years of monitor data that you want to use, deleting any specific data values, and choosing the minimum data requirements of monitors you want in your analysis.

· Monitor Data Years

. Choose the years of monitor data that you want to use. The default is to use the three-year period 2006-2008. (That is, for both IMPROVE-STN and PM2.5 monitor data, the Start Yearis 2006 and the End Yearis 2008 .) The default period is based on a modeling year of 2007. The start and end years should be changed to applicable time periods, depending on the base modeling year.

· Delete Specified Data Values

. The default is to delete the observations specified by EPA. As described in the Data Input section , valid data are given a value of "0" and observations that should be deleted are given a value of "1" to "10". (Leave unchecked theoption for the user to flag data.)Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 145 

### · Minimum Data Requirements

. There are three sets of minimum data requirements: 1. Minimum number of valid days per quarter . This is the minimum number of site-days per valid quarter. The default is 11 days, which corresponds to > 75% completeness for monitors on a 1 in 6 day schedule. This is a minimum number of samples that is routinely used in calculations of quarterly average concentrations. 2. Minimum number of valid quarters per valid year . This is the minimum required number of valid quarters for a valid year. The default for IMPROVE-STN monitor data is 1 quarter, and the default for PM2.5 monitor data is 4 quarters. If the value is set = 4, then all 4 quarters must be valid in order for a given year to be considered complete. 3. Minimum number of valid years required for valid monitor . This is the number of valid years that are needed in order for a particular monitor's data to be considered valid. The default is 1 for both IMPROVE-STN and PM2.5 monitor data. For example, if the value is = 1, then a monitor's data will be used in the species fractions calculations if it has at least one valid year. If the value = 3, then the monitor must have 3 years of valid data to be used. Use the default settings pictured in the screenshot below. (All of these options are described in detail here .)Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 146 

### When your window looks like the window above, click Next . This will bring you to the Species Fractions Calculation Options - Advancedwindow. 

## 6.6 Step 6. Species Fractions Calculation Options - Advanced
The Species Fractions Calculation Options - Advancedscreen allows you to make relatively advanced choices for your analysis. Generally speaking, the default options settings are consistent with the EPA modeling guidance document. The first set of options lets you specify which monitor data you want to use to characterize peak values (e.g., top 10 percent of daily monitor days). The second set of options allows you to specify the interpolation weighting that you want to use and whether the interpolation involves a maximum distance or not. The third set of options involves choices regarding ammonium,Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 147 

### blank mass, and organic carbon. Use the default settings pictured in the screenshot below. (All of these options are described in the Species Fractions Calculation Options - Advancedsection in the Daily PM Analysis: Details chapter.)

When your window looks like the window above, click Next . This will bring you to the PM2.5 Calculation Optionswindow.Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 148 

## 6.7 Step 7. PM2.5 Calculation Options
The PM2.5 Calculation Optionswindow allows you to specify the particular years of monitor data that you want to use from the input file you specified in Step 4(Data Input). Keep the default settings:

· PM2.5 Monitor Data Years

. Start Year = 2005and End Year = 2009

.

· Valid FRM Monitors . Keep the minimum number of design values equal to the default value of 1, and do not specify any particular design values for inclusion in the calculations.

· NH4 Future Calculation . You can also specify how you want to forecast NH4 values. Use the default approach, which is to use baseline DON values. Use the default settings pictured in the screenshot below. (All of these options are described in detail here .)

When your window looks like the window above, click Next . This will bring you to the Model Data Options window. 

## 6.8 Step 8. Model Data Options
The Model Data Optionssection allows you to specify three items:

· Temporal Adjustment at Monitor. This option specifies how many model grid cells to use in the calculation of RRFs for point and spatial estimates. Use the default option for both: 1x1 set of grid cells. Note that for PM analyses, MATS calculates meanDaily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 149 

### concentrations across the grid cell array. (Compare this with the maximum concentrations used for ozone analyses, however, in the case of a 1x1 set of grid cells the mean and maximum are the same.)

· Advanced Options: RRF Model Values Used . This option lets you specify which monitor data you want to use to characterize peak values (e.g., top 10 percent of daily model days). Use the default settings pictured in the screenshot below. (All of these options are described further here .)

When your window looks like the window above, click Next . This will bring you to the Final Check window. 

## 6.9 Step 9. Final Check The Final Check window verifies the choices that you have made. For example, it makes sure that the paths specified to each of the files used in your Configurationare valid. Click on the Press here to verify selectionsbutton.Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 150 

### If you encounter any errors, go back to the choices you have previously made by clicking on the appropriate part ( e.g. , Data Input) of the tree in the left panel, and then make any changes required. When your window looks like the window above, click either Save Scenario & Runor Save Scenario. Save Scenario & Run will cause MATS to immediately run the scenario. A temporary, new Runningtab will appear (in addition to the Start , Map Viewand Output Navigatortabs).Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 151 

### When the calculations are complete, a small window indicating the results are Donewill appear. Click OK

.

After clicking OK , MATS will open a folder with the results files already exported.Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 152 

### Output Navigatortab will also be active. (The Runningtab will no longer be seen.) MATS will automatically load the output files associated with the .asr configuration that just finished running.Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 153 

### The next step ( click here ) shows you how to map your results with the Output Navigator

. For more details on mapping and other aspects of the Output Navigator , there is a separate chapter on the Output Navigator

. 

## 6.10 Step 10. Map Output After generating your results, Output Navigatorcan be used to load and/or map them. If a run just finished, the output files will already be loaded into output navigator. (If files from a previous run need to be loaded then click on the Loadbutton and choose the Tutorial Daily PM.asr file.) Under Configuration/Log Files , you will see two files:

· Configuration : keeps track of the assumptions that you have made in your analysis.

· Log File : provides information on a variety of technical aspects regarding how a results file (*.ASR) was created. Under Output Filesyou will see four files with model data and one with forecasted design values:

· Tutorial Daily PM Baseline Quarterly Peak Model Data : contains baseline peak quarterly species and PM2.5 values for all grid-cells in the modeling domain.

· Tutorial Daily PM Future Quarterly Peak Model Data : contains future peak quarterly species and PM2.5 values for all grid-cells in the modeling domain.

· Tutorial Daily PM Used Baseline Quarterly Peak Model Data Point : contains only baseline peak quarterly species and PM2.5 values that were used in the analysis.

· Tutorial Daily PM Used Future Quarterly Peak Model Data Point : contains only baseline peak quarterly species and PM2.5 values that were used in the analysis.

· Tutorial Daily PM Daily PM25 Point : contains peak base & future PM2.5, species values, and RRFs. (Note that the annual RRFs and annual species values are not used anywhere in the calculation of design values, and are here just for information.) Right-click on the file Tutorial Daily PM Daily PM25 Point . This gives you three options: Add to Map , View , and Extract . Choose the Add to Mapoption.Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 154 

### This will bring up the Map Viewtab.

To view an enlarged map, use the Zoom to an areaTask Bar button on the far left.Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 155 

### Choose the Continental US

.

To more easily view the location of monitors in particular states, uncheck US Counties using the Standard Layersdrop down menu on the far right of the Task Bar. Your window should look like the following:Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 156 

### Zoom in further on the Eastern US using the Zoom inbutton on the Task Bar. This allows you to view the results more closely. A dashed line surrounds the area that you have chosen and should look something like the following:Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 157 

### Right click on the " Tutorial Annual PM Annual PM25 Point " layer in the panel on the left side of the window. Choose the Plot Valueoption.Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 158 

### This will bring up Shape Class Breakswindow. In the Valuedrop-down list, choose the variable " f_pm25_ann_dv " - this is forecasted PM2.5 design value. Set the Marker Sizingto 1 - this will give larger values a somewhat larger marker on the map.

Click Applyand then click Close . This will bring you back to the Map Viewwindow.

This is just a brief summary of the mapping possibilities available. For more details, there is a separate chapter on the Map View . The next stepis to go to the Output NavigatortoDaily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 159 

### view the data in a table format. 

## 6.11 Step 11. View Output After mapping your results, click on the Output Navigatortab, so that you can then view the data in a table. Right-click on the file Tutorial Daily PM Daily PM25 Point . This gives you three options: Add to Map , View , and Extract . Choose the Viewoption.

This will bring up a Monitor Network Datatab. The upper left panel allows you to view the ID and latitude and longitude of the monitors in your data -- at the right of this panel there is a scrollbar with which you can locate any particular monitor of interest.Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 160 

### To view the data for a particular monitor -- in this example, monitor ID = "010491003" -- highlight this monitor. MATS will then display the values for this monitor in the bottom panel.Daily PM Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 161 

### To view all of the data again, click on the Show Allbutton. For additional details on generating annual PM results, see the chapter on Daily PM Analysis: Details . For additional details on viewing data, see the View Data section in chapter on the Output Navigator

.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 162 

## 7 

# Daily PM Analysis: Details 7
MATS can forecast daily design values at PM2.5 monitor locations -- these forecasts are referred to as Point Estimates . The set of choices involved in calculating Point Estimates can be fairly involved, so MATS keeps track of these choices using a Configuration

. When you begin the process of generating PM2.5 estimates, MATS provides an option to start a new Configuration or to open an existing Configuration

.

Select your option and then click Go

. MATS will then step you through a series of windows with choices for your analysis.

· Output Choice . Choose whether you want to run the Standard Analysis, and whether to output a species fractions file and/or quarterly model data.

· Output Choice - Advanced . This option provides miscellaneous Point Estimate output files that are mainly used for QA.

· Data Input
. Load species monitoring data or a species fractions file. Load PM2.5 ambient monitoring data. And, load the modeling data that you want to use.

· Species Fractions Calculation Options . Choose the years of daily STN-IMPROVE and FRM monitoring data. Identify valid monitors. Delete specified values.

· Species Fractions Calculation Options - Advanced . Choose method to identify peak monitor values. Choose interpolation options for PM2.5 and species monitoring data. Choose assumptions for the ammonium calculation, default blank mass, and organic carbon.

· PM2.5 Calculation Options - FRM Monitor Data . Choose the years of quarterly FRM monitoring data. Identify valid monitors. Choose the approach for calculating future NH4.

· Model Data Options . Specify the maximum distance of monitors from modeling domain. Choose method to identify peak model values. Specify which model grid cells will be used when calculating RRFs at monitor locations.

· Final Check . Verifythe selections that you have made. 

## 7.1 Output Choice
In the Output Choicewindow, MATS lets you specify the name of your Scenario , andDaily PM Analysis: Details

April 2014 Abt Associates Inc. 163 

### then to choose up to three file options: Standard Analysis , which refers to forecasts made at FRM PM2.5 monitor locations; Quarterly Model Data , which allows you to create quarterly "peak" averages from daily model output data (output data from grid models such as CMAQ and CAMx), and then subsequently reuse this file; and Species Fractions , which outputs a reusable species fractions file. By checking the box next to Automatically extract all selected output files, MATS will create a separate folder with your chosen Scenario Name in the MATS "Output" folder, and then export .CSV files with the results of your analysis. Alternatively, you can export the results from the Output Navigator , but checking this box is a little easier.

Standard Analysis . The Standard Analysisrefers to the calculation of future year PM2.5 design values at FRM monitor locations. This is the main part of the modeled attainment test for PM2.5. There are several calculations involved in this analysis. MATS will interpolate PM2.5 species data, calculate species concentrations at each FRM site and project design values to a future year using gridded model data. Most MATS users will run this analysis and it is therefore checked by default. Quarterly Peak Model Data . MATS requires two types of data input: ambient monitor data and gridded model output data. For the daily PM2.5 calculations, MATS will accept either MATS formatted daily average gridded model files or quarterly peak average files. If daily average model files are used as inputs, MATS will calculate quarterly peak averages from the daily averages and optionally output the quarterly peak average concentrations into text files (CSV files). The quarterly average text files can then be re-used in subsequent MATS analyses. Quarterly average input files are smaller and runDaily PM Analysis: Details

April 2014 Abt Associates Inc. 164 

### faster than daily average files. Choosing this option will have MATS generate two types of quarterly peak average model concentration CSV files:

· All Data . MATS outputs quarterly peak data for allgrid cells in the modeling domain. MATS will create one baseline year file and one future year file. This will create relatively large files, but they will still be much smaller than daily average files.

· Used Data . MATS outputs quarterly peak data for the grid cells that are subsequently usedin the particular MATS configuration. For example, if MATS calculates future year design values at 20 FRM sites using a 1 X 1 grid array, then MATS will output base and future model values for only 20 grid cells (assuming each monitor is in a unique grid cell). The advantage of these files is that they are extremely small. But if subsequent MATS runs use a different set of monitors or grid arrays, then the files may not contain all of the necessary data to complete the analysis. This option is recommended as a QA tool to examine the grid cells and the model concentrations that MATS is using in the analysis. Species Fraction . Checking the “ Output species fraction file” box will create an output file containing the calculated PM2.5 species fractions at each FRM site used by MATS. This species fraction file can be re-used in MATS as an input file. The species fraction file can be useful for several reasons. One, using a species fraction file saves time because MATS won ’ t have to interpolate species data and calculate fractions each time it is run. Two, it can provide consistency between MATS runs by ensuring that the same species fractions are used each time. And for the same reason, the species fraction file can be used interchangeably between different users to ensure that multiple groups are using the same species fractions (if that is a goal). And finally, the fractions file can serve as a template for creating a custom species fractions file using whatever data and techniques (e.g. alternative interpolation techniques) are desired by any particular user. 

## 7.1.1 Scenario Name The Scenario Name allows you to uniquely identify each analysis that you conduct. It is used in several ways.

· Results file name . The results file is given the Scenario Name(e.g., Example Daily PM.asr). Note that the extension ( .ASR ) is specifically designated just for MATS and can only be used by MATS.

· Organize output . In the Output folder, MATS will generate a folder using the Scenario Name . MATS will use this folder as a default location for files generated with this Scenario Name.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 165 

### · Output file names . The output files generated will begin with the Scenario Name.



## 7.1.2 Standard Analysis Future-year PM2.5 design values are projected at each FRM monitoring site through a series of calculations:Daily PM Analysis: Details

April 2014 Abt Associates Inc. 166 

### Step 1

. Baseline Top 32 Ranked PM2.5 Calculation . MATS uses "official" daily PM2.5 data to select the eight highest daily PM2.5 values for each quarter for each year. Step 2

. Baseline Top 32 Ranked Species Calculation . MATS calculates species fractions using "unofficial" PM2.5 monitor data and speciated monitor data. It then multiplies the species fractions with the baseline PM2.5 concentrations selected in Step 1. Step 3

. Calculate Relative Response Factors (RRFs) . RRFs are calculated for each quarter and each species by dividing the future year quarterly peak modeled concentrations by the base year quarterly peak modeled concentrations. Step 4

. Forecasted Peak Species Calculation . Multiplying RRFs with baseline ambient species values, MATS calculates forecasted peak species values at each FRM monitor site. The species values are aggregated to obtain PM2.5 forecasted values. Step 5

. Forecasted Design Value Calculation . Using the forecasted values, MATS selects the 98th percentile PM2.5 for each year at each FRM monitor site. The design values are calculated as the averages of the 98th percentile values over three years. In this section, we go into some detail describing these steps. However, you should note that MATS gives you a number of options affecting the exact steps that MATS follows, such as determining which years of monitoring data to use and to choosing which monitors to include in the calculations. These options are detailed in the PM2.5 Calculation Options section. The output from the Standard Analysis is described here

. 7.1.2.1 Step 1: Baseline Top 32 Ranked PM2.5 Calculation The first step in projecting the daily design value is to identify the eight highest daily PM2.5 concentrations in each quarter over the entire year. This results in 32 data points for each year (2005-2009 by default) for each FRM site. For each of these values, future values will be forecast using the process outlined in the next two sections. Please note that each of the 32 data points records a variable called "Rank 98". This variable indicates the position of the value representative of the 98th percentile with regards to PM if the 32 data points were sorted in descending order on their PM2.5 values. This variable value is identical for all data points in a given year and is used to determine the forecasted "98th Percentile" value later in the computation. The Rank 98 value is based on the actual rank of the 98th percentile value in the ambient FRM data for each site for each year. It is based on the number of samples per year.

7.1.2.2 Step 2: Baseline Top 32 Ranked Species Calculation Since the FRM monitors do not have speciated data (and the majority of FRM sites are not co-located with a speciation monitor), MATS uses speciated PM2.5 monitor data from other monitoring networks, such as STN and IMPROVE, to estimate the PM2.5 attributable to the following species: sulfate (SO4), nitrate (NO3), elemental carbon (EC), organic carbon (OC), crustal matter, particle bound water (PBW), ammonium (NH4), and, data permitting, salt.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 167 

### To estimate these species, MATS uses the “SANDWICH” process (Frank, 2006) (SANDWICH stands for Sulfates, Adjusted Nitrates, Derived Water, Inferred Carbonaceous mass, and estimated aerosol acidity [H+]). The default species input data file contains aerosol nitrate data (NO3r) that has been adjusted to account for volatilization. Additional SANDWICH adjustments are made within MATS. These include calculation of particle bound water (PBW) and organic carbon by mass balance (OCMmb). Determine Valid Days and Calculate Peak Quarterly Averages for Speciated Monitor Data A first step in calculating baseline peak species values is deleting invalid days of data. MATS deletes days from the speciated monitor data that are missing “MEASURED_FM” values. Days that have a “EPA FLAG” value greater than “0” are also deleted. MATS then uses the Minimum Data Requirements specified on the Species Fractions Calculations Options tab, to delete data that are incomplete for a particular species. In the default case, there should be 11 days each quarter, at least 1 valid quarter per valid year, and at least 1 valid year per valid monitor. In the default case, only the specification of a minimum number of values per quarter has any effect on the data. If a particular quarter in a given year for a given species does not have 11 non-missing species values, then data for that species is dropped for that particular quarter at that monitor. The number of peak days is then calculated. In the default case, the top 10% of days = round (0.10*non-missing days in quarter). The speciated monitor data is then sorted on “MEASURED_FM” at each monitor, for each year and quarter, and the peak days are chosen. (Options for choosing peak days are described in the Species Fractions Calculation Options - Advancedsection.) MATS then averages the peak daily values in each year-quarter, and then averages the values across years. For example, if for 2002-2004 we have SO4 averages of peak values in quarter 1 of 8.2 ug/m 3 

### (for 2002), 6.2 ug/m 3 

### (for 2003), and 3.6 ug/m 3 

### (for 2004), then the average across the years would equal 6.0 (=[8.2+6.2+3.6]/3). Interpolate Quarterly Species Values to FRM Monitors About 75 percent of FRM monitors are not co-located with an STN monitor, so the estimation of the quarterly peaks of the individual species at these FRM sites depends on theinterpolatedquarterly peaks from speciated monitors (e.g., IMPROVE). Individual species are interpolated to the latitude and longitude associated with each FRM monitor. (For FRM monitors that areco-located with an STN monitor, MATS simply uses the species values from the co-located STN monitor.) For the speciated monitors that are not co-located, MATS uses the Voronoi Neighbor Averaging (VNA ) procedure to interpolate the peak quarterly species values to FRM monitors. The VNA procedure identifies the nearby ("neighbor") speciated monitors for each FRM site, and then assigns a weight to each speciated monitor that gets used to generate an initial, weighted-average for each species at each FRM site. Generally speaking, speciated monitors that are relatively far away get a smaller weight. (You canDaily PM Analysis: Details

April 2014 Abt Associates Inc. 168 

### find details on the interpolation process and different options for interpolation at the section on Interpolation Options for Species Fractions Calculation .) After Interpolation to FRM Monitors: SANDWICH and Species Fractions Calculations After the interpolation of quarterly values for retained NO3 (NO3r), SO4, OCb, crustal, EC, and DON, a few additional steps are necessary to generate speciated values at each FRM monitor site. These include calculating retained NH4 (NH4r), PBW, blank mass, and organic carbon mass (OCMMB), the latter of which is calculated through a mass balance approach. (The following sections describe the calculations of ammonium , PBW , and organic carbon[by difference], as well as the blank massassumption.) After generating quarterly values at each FRM monitor site, MATS can then calculate the species fractions. (The species fractions calculations are straightforward and are described further in the Species Fractions section.) Summary of Calculations After Interpolation of STN & IMPROVE Speciated Monitor Data Calculation Description Calculate Retained Ammonium (NH4r) Calculate ammonium associated with retained nitrate (NO3r) and SO4. MATS calculates NH4r using DON, SO4, and NO3r. (Alternatively MATS can use directly measured ammonium). Calculate Particle Bound Water (PBW) Calculate amount of water associated with ammonium sulfate and ammonium nitrate, which are hygroscopic. Estimate Blank Mass Account for contamination on FRM monitor filters. Calculate Organic Carbon Mass (OCMMB) Calculate organic carbon mass with a mass balance approach. Calculate Species Fractions Divide species estimates for SO4, NO3r, OCMMB, EC, crustal material, NH4r, and PBW by the non-blank PM2.5 mass. (The inclusion of salt is optional.)



### Using Species Fractions to Estimate Top 32 Ranked Species Values The use of species fractions to calculate species concentrations is straightforward. The weighted species average is calculated by multiplying the top 32 ranked FRM baseline values (calculated in Step 1, minus the assumed blank mass, specified by the user) with species fractions for the corresponding quarter that have been estimated for each FRM monitor. The calculation is as follows:Daily PM Analysis: Details

April 2014 Abt Associates Inc. 169 

### Note that MATS calculates species fractions from speciated monitors for a limited number of years. As a result, rather than have species fractions specifically calculated for each quarter and each year, MATS uses a single set of quarter-specific species fractions to calculate the weighted peak average species concentrations. The species data should be "representative" of the species fractions that occur during the 5-year FRM monitoring period selected in MATS. Example Calculation Baseline Species Concentrations MATS multiplies the (non-blank) top 32 ranked baselinePM2.5 values. Below is an example showing the calculation for four data points in the same year. Day FRM PM2.5 Blank Mass Non-Blank Mass
2/10 10.4175 0.5 9.9175 5/5 11.4941 0.5 10.9941 8/7 13.0624 0.5 12.5624 11/4 10.5773 0.5 10.0773 

### with the species fractions calculated for this particular site: Quarter SO4 NO3 OCMMB EC PBW NH4 Crustal (Salt) Q1 0.2382 0.1108 0.3346 0.0201 0.1049 0.1209 0.0705

-- Q2 0.2637 0.0727 0.3178 0.0545 0.1095 0.1273 0.0545

-- Q3 0.1432 0.0557 0.5621 0.0238 0.0959 0.0955 0.0238

-- Q4 0.2580 0.1389 0.2756 0.0396 0.1094 0.1190 0.0595

-- 

### The product is the estimated baseline species concentrations. Day SO4 NO3 OCMMB EC PBW NH4 Crustal 2/10 2.3623 1.0989 3.3184 0.1993 1.0403 1.1990 0.6992 5/5 2.8991 0.7993 3.4939 0.5992 1.2039 1.3996 0.5992 8/7 1.7989 0.6997 7.0613 0.2990 1.2047 1.1997 0.2990 11/4 2.5999 1.3997 2.7773 0.3991 1.1025 1.1992 0.5996

Retained Ammonium Calculation 

### MATS calculates retained ammonium two different ways. The default approach is to use interpolated degree of neutralization of sulfate (DON) values from the speciated monitors. The alternative approach is to use interpolated NH4 values from speciated monitors (e.g., STN). In the Species Fractions Calculations Options - Advancedsection, you have the option to choose the approach that you prefer to use. The two approaches are described here. Default approach using measured pre-calculated DON, SO4, and retained NO3 (NO3r):Daily PM Analysis: Details

April 2014 Abt Associates Inc. 170 

### Because of uncertainties in NH4 speciation measurements, by default MATS calculates ammonium values using the degree of sulfate neutralization (DON). MATS uses precalculated daily DON values that are included in the species data input file ("Species-forfractions-xxxx.csv"). The values for DON are calculated from the amount of ammonium associated with sulfate (NH4 SO4 

### ) as follows:

And the estimated NH4 SO4

### is calculated as follows:

where 0.29 is the molar ratio of NH4 to NO3 and NH4 measured

### and NO 3 retained

### reflect the amounts of NH4 and NO3 retained on the FRM filter. The amount of NH4 SO4

### is not allowed to exceed the fully neutralized amount of 0.375 multiplied by the estimated sulfate ion concentration. MATS then calculates ammonium using interpolated monitor values of DON, SO4, and NO3r as follows:

Alternative Approach Using Measured Ammonium . The alternative approach is to use interpolated NH4 values from STN monitors. This approach has several steps. First, MATS calculates “adjusted” NH4:

where the PctEvap factor refers to the percentage of ammonium associated with the volatilized nitrate that is also lost. (As discussed in the Species Fractions Calculation Options - Advancedsection, this factor is adjustable from 0 to 100 percent.) The default assumption is that no ammonium is volatilized (0 percent). Second, MATS calculates NH4 associated with SO4:

Third, MATS calculates DON:

Finally, using the same equation as in the default approach, MATS calculates NH4r by substituting the calculated DON for the interpolated (measured) DON value:Daily PM Analysis: Details

April 2014 Abt Associates Inc. 171 Particle Bound Water Calculation 

### Because ammoniated sulfate and ammonium nitrate are hygroscopic, the retained sulfate and nitrate mass will include water. Particle bound water (PBW) is estimated using the Aerosol Inorganic Model (AIM) (Clegg et al, 1998) . For computational convenience, a polynomial regression equation was fit to the calculated water mass from AIM and the three input values that fed into AIM (sulfate, nitrate and ammonium). AIM was run with typical FRM filter equilibration conditions of 35% RH and 22 deg C (295 deg K). MATS calculates particle-bound water (PBW) using levels of SO4, NO3r, and NH4r as follows. (Note that this is the same equation that MATS uses to calculate future-year PBW, the difference being the future-year PBW uses future-year values of SO4, NO3r, and NH4r, and here MATS uses base-year values.) The calculation uses one of two equations, depending on the acidity of the ammoniated sulfate (represented by DON). S, N, and A in the equations are the relative fraction of SO4, NO3r, and NH4r respectively. S = SO4 / (SO4 + NO3r + NH4r); N = NO3r / (SO4 + NO3r + NH4r); A = NH4r / (SO4 + NO3r + NH4r); if DON le 0.225 then PBW = {595.556 - 1440.584*S - 1126.488*N + 283.907*(S**1.5) - 13.384*(N**1.5) - 1486.711*(A**1.5) + 764.229*(S**2) + 1501.999*(N*S) + 451.873*(N**2) - 185.183*(S**2.5) - 375.984*(S**1.5)*N - 16.895*(S**3)Daily PM Analysis: Details

April 2014 Abt Associates Inc. 172 

### - 65.814*(N**1.5)*S + 96.825*(N**2.5) + 83.037*(N**1.5)*(S**1.5) - 4.419*(N**3) + 1720.818*(A**1.5)*S + 1220.383*(A**1.5)*N - 311.496*(A**1.5)*(S**1.5) + 148.771*(A**1.5)*(N**1.5) + 1151.648*(A**3)} * (SO4+NO3r+NH4); ELSE PBW = {202048.975 - 391494.647 *S - 390912.147 *N + 442.435 *(S**1.5) - 155.335 *(N**1.5) - 293406.827 *(A**1.5) + 189277.519 *(S**2) + 377992.610 *N*S + 188636.790 *(N**2) - 447.123 *(S**2.5) - 507.157 *(S**1.5)*N - 12.794 *(S**3) + 146.221 *(N**1.5)*S + 217.197 *(N**2.5) + 29.981 *(N**1.5)*(S**1.5) - 18.649 *(N**3) + 216266.951 *(A**1.5)*S + 215419.876 *(A**1.5)*NDaily PM Analysis: Details

April 2014 Abt Associates Inc. 173 

### - 621.843 *(A**1.5)*(S**1.5) + 239.132 *(A**1.5)*(N**1.5) + 95413.122 *(A**3)} * (SO4+NO3r+NH4) . Organic Carbon Mass Calculation 

### Measured organic carbon mass is not directly used in the calculation of species fractions in MATS because of (1) many uncertainties in estimating carbonaceous mass from carbon measurements (Turpin & Lim, 2001; Chow et al, 2004) (2) differences in carbon measurement protocol between urban and rural monitoring locations, (3) a relatively “bumpy” surface of urban carbon concentrations as derived from urban and rural organic carbon measurements and (4) lack of carbon measurements at all FRM locations. The MATS approach estimates carbon by mass balance comparing precisely measured FRM PM2.5 mass (EPA, 2003) with the sum of its non-carbon components. Total carbonaceous mass contains both elemental carbon (EC) and organic carbon mass (OCM). We measure EC from the interpolated STN and IMPROVE monitors, while we calculate OCM using a mass balance approach -- and refer to it as OCMMB. To calculate OCMMB, we subtract the other estimated retained species (including EC) from the PM2.5 level measured at the FRM site as follows:

The value for OCMMB could be very small, or even be calculated as negative (if the sum of the species enclosed in the curly brackets exceeded the FRM PM2.5 monitor value). To ensure that the OCMMB does not get too small, an OCMMB "mass balance floor" (default) value is set to 1.0 times the interpolated value of blank-adjusted organic carbon (OCb). It is also possible that the value of the floor by itself could exceed the FRM total PM2.5 value. In this case, MATS imposes a (user-adjustable) "ceiling," such that OCMMB does not exceed a percentage of the total non-blank mass. The default ceiling value is set to 0.8 or 80% of PM2.5 mass. (You can modify the floor and ceiling assumptions in the Species Fractions Calculation Options - Advancedwindow.) To account for these possibilities, MATS uses the following series of equations to calculate OCMMB:

where the " Floor " variable has a default value in MATS of "1.0" and the " Ceiling " variableDaily PM Analysis: Details

April 2014 Abt Associates Inc. 174 

### has a default value in MATS of "0.8". There are at least two things to note with this approach. (1) When the final OCMMB value is equal to the "floor," then the sum of the species will exceed the PM2.5 value at the FRM monitor. To ensure that the sum of the species just equals the FRM PM2.5 value, MATS reduces all of the species (except OCMMB) by the same percentage until the sum of the species just equals the FRM PM2.5 value. (2) When the final OCMMB value is equal to the "ceiling," then the sum of the species will be less than the PM2.5 value at the FRM monitor. In that case, MATS increases all of the species by the same percentage until the sum of the species just equals the FRM PM2.5 value
Blank Mass Assumption 

### The field blank typically has a value of between 0.3 and 0.5 ug/m 3 

### , which appears to result from contamination of the FRM filter. For calculating retained PM2.5, MATS uses a default blank mass value of 0.5 ug/m 3 

### . If desired, you can change the default blank mass value at the Species Fractions Calculations Options - Advancedwindow.
7.1.2.3 Step 3: Calculate Relative Response Factors Relative response factors (RRFs) are calculated as the ratio of the modeled forecasted species to the modeled baseline species. In other words, baseline species concentrations are assumed to change in the same proportion as the model data in the same location from the baseline to the forecasted.

where :
RRFi,Q= relative response factor for species "i" in quarter Q

Model i,futureQ = Modeled forecasted species “i” peak in quarter Q
Model i,baseQ = Modeled baseline species “i” peak in quarter Q 

### MATS calculates RRFs for each quarter for each of six species: SO4, NO3, OCM, EC, crustal material, and (optionally) NH4. (Additional information on the calculation of the RRFs can be found in the Model Data Options section.)

7.1.2.4 Step 4: Forecasted Peak Species Calculation To calculate forecasted peak species values, MATS uses each valid baseline peak species value and the RRFs calculated from baseline and forecasted (e.g., 2020) air quality modeling. If five years of species estimates are available and if all quarters are valid, then this calculation gives 160 estimates (32*5) for each species. Because this calculation involves modeling data from two different years (a base year and a future year), this isDaily PM Analysis: Details

April 2014 Abt Associates Inc. 175 

### referred to as a "temporal adjustment." The forecasted weighted peak for each species is calculated by multiplying the baseline quarterly peak values for each monitor species with the quarterly RRF for that species. This process gives 32 peak values per year of six species: SO4, NO3, OCM, EC, crustal material, and NH4. The form of the equation for each species is as follows (Please note that these computations are repeated 32 times, once for each set of peak species values!):

where : Species i,futureY,D= Estimated forecasted species “i” peak in year Y and top 32 ranked day D Species i,baseY,D= Monitored baseline species “i” peak in year Y and top 32 ranked day D
RRFi,Q= relative response factor for species "i" in quarter Q 

### Additional calculations are needed to estimate future-year peak values of NH4 and particle-bound water (PBW), which is calculated using forecasted levels of NH4, NO3, and SO4. (Details on the PBW calculation can be found here .) Recall that the default base year NH4 calculation is as follows:

MATS can calculate the future year NH4 concentration using modeled NH4 RRFs, or by using the the base year DON value combined with future year SO4 and NO3 values (default approach) as follows:

The option for choosing which approach to use for calculating future NH4 is given in the PM2.5 Calculation Optionswindow. Finally, note that PBW is calculated after future year NH4, using the previously identified water equation and future year concentrations of NH4, SO4, and NO3. Example Calculation Forecasted Species Concentrations Using RRFs MATS multiplies the baseline species concentrations for SO4, NO3, OCMMB, EC, and Crustal. Below is an example showing the calculation for one year of data. Note, however, that if all five years and all quarters of baseline quarterly peak PM2.5 (calculated in Step 1) are valid, then there will be 32 sets of species values for each of five years. Quarter SO4 NO3 OCMMB EC PBW NH4 Crustal 1 2.3623 1.0989 3.3184 0.1993 1.0403 1.199 0.6992Daily PM Analysis: Details

April 2014 Abt Associates Inc. 176 Quarter SO4 NO3 OCMMB EC PBW NH4 Crustal 1 2.253966 1.059887 3.052326 0.192227 0.957682 1.14892 0.650875 1 2.153474 0.960213 3.008953 0.18716 0.941016 1.127472 0.629825 1 2.018054 0.92684 2.948333 0.180317 0.920214 1.072046 0.581908 1 1.883425 0.836795 2.883676 0.179808 0.849054 1.069356 0.564332 1 1.719184 0.818943 2.600576 0.165809 0.831113 0.982041 0.540465 1 1.704355 0.737319 2.477937 0.156328 0.757506 0.929672 0.515625 1 1.624759 0.696826 2.345071 0.14772 0.690914 0.849403 0.477717 2 2.8991 0.7993 3.4939 0.5992 1.2039 1.3996 0.5992 2 2.863181 0.728432 3.301485 0.557751 1.197191 1.329165 0.587084 2 2.847375 0.721621 3.054537 0.525272 1.183466 1.250154 0.568748 2 2.779412 0.720248 2.918015 0.501874 1.075874 1.187874 0.53307 2 2.523706 0.689026 2.759803 0.457018 0.97586 1.106502 0.507829 2 2.302765 0.666994 2.613514 0.446125 0.967615 1.098137 0.489328 2 2.264156 0.621376 2.519566 0.430883 0.891127 1.020688 0.460858 2 2.126643 0.613058 2.271892 0.40016 0.883748 0.946814 0.451779 3 1.7989 0.6997 7.0613 0.299 1.2047 1.1997 0.299 3 1.779318 0.69014 6.817854 0.29281 1.112251 1.192717 0.276236 3 1.625583 0.652832 6.644656 0.274995 1.004904 1.11704 0.269622 3 1.499236 0.605743 6.146527 0.262567 0.923129 1.012394 0.257635 3 1.416128 0.569719 5.763759 0.241669 0.841649 0.935202 0.251172 3 1.343383 0.526069 5.496105 0.238273 0.834924 0.934347 0.246456 3 1.283216 0.509961 5.42566 0.238036 0.8062 0.897558 0.222655 3 1.250273 0.479969 5.275127 0.22308 0.758142 0.832071 0.214994 4 2.5999 1.3997 2.7773 0.3991 1.1025 1.1992 0.5996 4 2.472886 1.380473 2.650604 0.385612 1.073826 1.113676 0.585284 4 2.374537 1.26463 2.471683 0.35995 1.027229 1.103675 0.546542 4 2.145454 1.13918 2.416613 0.354706 0.97877 1.096208 0.519894 4 1.993059 1.12821 2.205443 0.353203 0.954289 1.034843 0.494129 4 1.889724 1.05256 2.003872 0.32705 0.860628 1.016929 0.450157 4 1.71124 0.96074 1.822678 0.308817 0.823144 0.984487 0.410878 4 1.683092 0.957319 1.821362 0.288313 0.79719 0.973683 0.394142 

### with the RRFs for each quarter and species: Quarter SO4 NO3 OCMMB EC PBW NH4 Crustal 1 0.9737 0.9873 0.9636 0.9872

-- -- 0.9808 2 0.9898 0.9991 0.9979 0.9917

-- -- 0.9891 3 0.9784 0.9775 0.9875 0.9944

-- -- 0.9759 4 0.97 0.98 0.9761 0.9843

-- -- 0.9818 

### The product is the forecasted species concentrations by day (typically 8 days per quarter). Quarter SO4 NO3 OCMMB EC PBW NH4 Crustal 1 2.300172 1.084944 3.19761 0.196749

-- -- 0.685775 1 2.194687 1.046427 2.941222 0.189766

-- -- 0.638378Daily PM Analysis: Details

April 2014 Abt Associates Inc. 177 Quarter SO4 NO3 OCMMB EC PBW NH4 Crustal 1 2.096837 0.948018 2.899427 0.184765

-- -- 0.617732 1 1.964979 0.915069 2.841014 0.178009

-- -- 0.570735 1 1.833891 0.826168 2.77871 0.177506

-- -- 0.553497 1 1.67397 0.808542 2.505915 0.163687

-- -- 0.530088 1 1.65953 0.727955 2.38774 0.154327

-- -- 0.505725 1 1.582028 0.687977 2.25971 0.145829

-- -- 0.468544 2 2.869529 0.798581 3.486563 0.594227

-- -- 0.592669 2 2.833976 0.727777 3.294552 0.553121

-- -- 0.580685 2 2.818332 0.720972 3.048122 0.520912

-- -- 0.562549 2 2.751062 0.719599 2.911887 0.497709

-- -- 0.52726 2 2.497964 0.688406 2.754007 0.453224

-- -- 0.502294 2 2.279277 0.666394 2.608026 0.442422

-- -- 0.483994 2 2.241062 0.620817 2.514275 0.427307

-- -- 0.455835 2 2.104951 0.612506 2.267121 0.396839

-- -- 0.446855 3 1.760044 0.683957 6.973034 0.297326

-- -- 0.291794 3 1.740885 0.674612 6.732631 0.291171

-- -- 0.269579 3 1.59047 0.638144 6.561598 0.273455

-- -- 0.263124 3 1.466852 0.592114 6.069696 0.261096

-- -- 0.251426 3 1.38554 0.556901 5.691712 0.240316

-- -- 0.245119 3 1.314366 0.514233 5.427404 0.236939

-- -- 0.240516 3 1.255499 0.498487 5.357839 0.236703

-- -- 0.217289 3 1.223267 0.46917 5.209188 0.221831

-- -- 0.209812 4 2.521903 1.371706 2.710923 0.392834

-- -- 0.588687 4 2.3987 1.352864 2.587255 0.379558

-- -- 0.574631 4 2.303301 1.239337 2.41261 0.354298

-- -- 0.536595 4 2.08109 1.116396 2.358856 0.349137

-- -- 0.510432 4 1.933267 1.105646 2.152733 0.347657

-- -- 0.485136 4 1.833033 1.031509 1.955979 0.321916

-- -- 0.441964 4 1.659903 0.941525 1.779116 0.303969

-- -- 0.4034 4 1.632599 0.938173 1.777832 0.283786

-- -- 0.386968 

### As discussed earlier, PBW and the (default) NH4 are calculated based on other species and not directly from RRFs.
7.1.2.5 Step 5: Forecasted Design Value Calculation The forecasted top 32 ranked values for all species are then added together to get forecasted top 32 ranked PM2.5 values for each year of monitor data (in rare cases there may be less than 32 forecasted values due to missing data):Daily PM Analysis: Details

April 2014 Abt Associates Inc. 178 

### This procedure is repeated for each of the years of monitoring data (e.g., 2005-2009). The forecasted values are then sorted high to low. The value at the position indicated by the Rank 98 variable in each year (as in 7.1.2.1, Step 1 ) is then taken to be the representative final forecasted design value for the year ( PM 2.5, Y

–it will be referred to as the estimated 98th percentile value going forward).
PM 2.5, Y = PM 2.5, Y, Rank 98 

### The forecasted 98th percentile values for each of the 5 years are averaged over 3 year intervals (e.g., 2005-2007, 2006-2008, 2007-2009):

The design value is then the average of the three peak design values, creating 5-year weighted averages for each monitor:

The output file containing the results of this Standard Analysis are described here

. Example Calculation Forecasted Design Values Using hypothetical data from the previous example calculation plus PBW values and assumed blank mass, MATS sums the species to get peak PM2.5 values for each year. The following table shows the calculations for one year (2005), with the selected 98th percentile value in bold italics. In reality, there would be four additional years of data, each with the same format as the table below. Forecasted Species Concentrations Day Year Quarter SO4 NO3 OCMM B EC PBW NH4 Crustal Blank Mass Salt Mass Rank 98 PM2.5

20050727 2005 3 8.4849 0 11.4993 1.1421 2.6976 2.5964 1.9296 0.5 0.045 4 28.8949
20050624 2005 2 5.6601 0 13.2829 1.0199 2.0787 1.9244 1.5417 0.5 0.0716 4 26.0793
20050805 2005 3 6.5993 0 8.9439 0.8883 2.0981 2.0194 1.5008 0.5 0.035 4 22.5848
20050913 2005 3 6.3731 0 8.6373 0.8578 2.0262 1.9502 1.4493 0.5 0.0338 4 21.8277
20051019 2005 4 4.6897 0.2708 9.2791 1.4062 1.6759 1.809 1.6536 0.5 0.1708 4 21.4551
20051001 2005 4 4.4206 0.2552 8.7467 1.3255 1.5797 1.7052 1.5587 0.5 0.161 4 20.2526Daily PM Analysis: Details

April 2014 Abt Associates Inc. 179 Forecasted Species Concentrations Day Year Quarter SO4 NO3 OCMM B EC PBW NH4 Crustal Blank Mass Salt Mass Rank 98 PM2.5

20050826 2005 3 5.6943 0 7.7173 0.7664 1.8104 1.7425 1.295 0.5 0.0302 4 19.5561
20050910 2005 3 4.9778 0 6.7463 0.67 1.5826 1.5232 1.132 0.5 0.0264 4 17.1583
20050621 2005 2 3.6838 0 8.645 0.6638 1.3529 1.2525 1.0034 0.5 0.0466 4 17.148
20051031 2005 4 3.6902 0.2131 7.3016 1.1065 1.3187 1.4235 1.3012 0.5 0.1344 4 16.9892
20050122 2005 1 2.6556 0.0487 9.4565 1.2007 0.9542 0.9967 1.0406 0.5 0.074 4 16.927
20050820 2005 3 4.8647 0 6.5929 0.6548 1.5466 1.4886 1.1063 0.5 0.0258 4 16.7797
20050326 2005 1 2.5838 0.0473 9.201 1.1683 0.9284 0.9697 1.0124 0.5 0.072 4 16.4829
20050630 2005 2 3.4783 0 8.1627 0.6267 1.2774 1.1826 0.9474 0.5 0.044 4 16.2191
20050519 2005 2 3.415 0 8.0143 0.6153 1.2542 1.1611 0.9302 0.5 0.0432 4 15.9333
20050904 2005 3 4.563 0 6.1841 0.6142 1.4507 1.3963 1.0377 0.5 0.0242 4 15.7702
20050507 2005 2 3.3676 0 7.9029 0.6068 1.2368 1.145 0.9173 0.5 0.0426 4 15.719
20050724 2005 3 4.3744 0 5.9285 0.5888 1.3908 1.3386 0.9948 0.5 0.0232 4 15.1391
20050528 2005 2 3.1304 0 7.3464 0.5641 1.1497 1.0643 0.8527 0.5 0.0396 4 14.6472
20050522 2005 2 2.9723 0 6.9754 0.5356 1.0916 1.0106 0.8096 0.5 0.0376 4 13.9327
20051010 2005 4 2.9791 0.172 5.8945 0.8933 1.0646 1.1492 1.0504 0.5 0.1085 4 13.8116
20050119 2005 1 2.1101 0.0387 7.5141 0.9541 0.7582 0.792 0.8268 0.5 0.0588 4 13.5528
20050510 2005 2 2.8775 0 6.7528 0.5185 1.0568 0.9783 0.7838 0.5 0.0364 4 13.5041
20050110 2005 1 2.024 0.0371 7.2074 0.9151 0.7273 0.7596 0.7931 0.5 0.0564 4 13.02
20051109 2005 4 2.71 0.1565 5.3621 0.8126 0.9684 1.0454 0.9556 0.5 0.0987 4 12.6093
20051004 2005 4 2.6908 0.1554 5.3241 0.8068 0.9616 1.038 0.9488 0.5 0.098 4 12.5235
20050227 2005 1 1.8948 0.0347 6.7474 0.8567 0.6808 0.7111 0.7425 0.5 0.0528 4 12.2208
20051224 2005 4 2.5947 0.1498 5.1339 0.778 0.9272 1.0009 0.9149 0.5 0.0945 4 12.0939
20051013 2005 4 2.537 0.1465 5.0198 0.7607 0.9066 0.9786 0.8946 0.5 0.0924 4 11.8362
20050221 2005 1 1.7513 0.0321 6.2362 0.7918 0.6293 0.6573 0.6862 0.5 0.0488 4 11.333
20050125 2005 1 1.6795 0.0308 5.9806 0.7594 0.6035 0.6303 0.6581 0.5 0.0468 4 10.889
20050101 2005 1 1.579 0.0289 5.6228 0.7139 0.5674 0.5926 0.6187 0.5 0.044 4 10.2673 

### Then MATS selects the 98th percentile concentration in each year based on the variable "Rank 98" (e.g., 21.8277 for year 2005, which corresponds to the row in bold italics in the table above): Day Year Annual Peak 20050913 2005 21.8277 20060818 2006 19.4299 20070807 2007 19.6192 20080530 2008 15.2901 20090305 2009 14.7958 

### These annual peaks are then averaged for each three-year period, and then MATS averages these three-year averages to get the forecasted peak design value:Daily PM Analysis: Details

April 2014 Abt Associates Inc. 180 Year Annual Peak 2005-2007 20.29226667 2006-2008 18.11306667 2007-2009 16.56836667 Forecasted Design Value 18.32456667



### 7.1.2.6 Output Description The output file is named " Daily PM25 Point.csv " with the Scenario Nameappended at the beginning (e.g., " Example Daily PM Daily PM25 Point.csv "). The table below describes the variables in the output file for the Standard Analysis

. Note the following: The RRF variables in this file are not the actual RRFs used to calculate future peak PM2.5 and PM2.5 species. They are the effective RRFs calculated by dividing the future peak concentrations (in this file) by the base year peak concentrations (in this file). The actual RRFs are calculated on a quarterly basis and are contained in the quarterly peak output files. Even though there are no quarterly RRFs for water or NH4 (if DON, NO3, and SO4 are used to calculate NH4), the resultant RRFs are included in the quarterly peak output files, based on the future year water and NH4 concentrations divided by the base year water and NH4 concentrations. Output file name: "Scenario Name + Daily PM25 Point" Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _type FRM data _STATE_NAME State name. (This is a character variable.) _COUNTY_NAM E County name. (This is a character variable.) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_gridcell Identifier of grid cell closest to the monitor b_pm25_d_DV Base year 5 year weighted average PM2.5 24-hr average (daily) design value f_pm25_d_DV Future year 5 year weighted average PM2.5 24-hr average (daily) design value b_blank_mass Base year blank mass concentration (ug/m3) b_crustal_mass Base year crustal mass concentration (ug/m3) b_EC_mass Base year elemental carbon mass concentration (ug/m3)Daily PM Analysis: Details

April 2014 Abt Associates Inc. 181 b_NH4_mass Base year ammonium mass concentration (ug/m3) b_Ocmb_mass Base year organic carbon mass (by difference) concentration (ug/m3) b_SO4_mass Base year sulfate ion mass concentration (ug/m3) b_NO3_mass Base year nitrate ion mass concentration (ug/m3) b_water_mass Base year water mass concentration (ug/m3) b_salt_mass Base year salt mass concentration (ug/m3) f_blank_mass Future year blank mass concentration (ug/m3) f_crustal_mass Future year crustal mass concentration (ug/m3) f_EC_mass Future year elemental carbon mass concentration (ug/m3) f_NH4_mass Future year ammonium mass concentration (ug/m3) f_Ocmb_mass Future year organic carbon mass (by difference) concentration (ug/m3) f_SO4_mass Future year sulfate ion mass concentration (ug/m3) f_NO3_mass Future year nitrate ion mass concentration (ug/m3) f_water_mass Future year water mass concentration (ug/m3) f_salt_mass Future year salt mass concentration (ug/m3) rrf_crustal Resultant annual relative response factor- Crustal Mass rrf_ec Resultant annual response factor- Elemental Carbon Mass rrf_nh4 Resultant annual relative response factor- Ammonium Mass. rrf_oc Resultant annual relative response factor- Organic Carbon Mass rrf_so4 Resultant annual relative response factor- Sulfate Mass rrf_no3 Resultant annual relative response factor- Nitrate Mass rrf_water_mass Resultant annual relative response factor- Water Mass rrf_salt Resultant annual relative response factor- Salt Mass (set equal to 1 if modeled salt is not used) 

## 7.1.3 Quarterly Peak Model Data The Quarterly Peak Model Dataoption gives you the option of creating a small, reusable file with quarterly peak values from a much larger file with daily values. Since daily PM2.5 MATS works with quarterly peak values there is no loss of precision. To save time, it is possible to use daily values only for an initial run with MATS and check this Quarterly Peak Model Dataoption. Then for subsequent runs (that use the same modeled data), use the quarterly file that MATS generates. However, this will only work for subsequent MATS runs that use exactly the same base and future year photochemical model data (such as sensitivity runs that test the various ambient data settings in MATS). Alternatively, you can generate a baseline and future quarterly average model file outside of MATS (using a program such as SAS, STATA, etc), and then load these quarterly files into MATS, bypassing the use of any daily model data in MATS. The format of the quarterly file is described below. MATS generates baseline and future model files for the complete model domain:Daily PM Analysis: Details

April 2014 Abt Associates Inc. 182 

### · Base-year file: " Baseline Quarterly Peak Model Data.csv " with the Scenario Name (e.g., Example Daily PM) appended at the beginning (e.g., " Example Daily PM Baseline Quarterly Peak Model Data.csv ").

· Future year file: "FutureQuarterly Peak Model Data.csv ." MATS also produces a set of "used" quarterly peak model files (base and future). These have the same format as the complete quarterly peak model data files, but only contain data for the model grid cells that were used in the MATS point calculations. These files can also be re-used and are also useful for QA purposes.

· Base-year file: " Used Baseline Quarterly Peak Model Data Point.csv. "

· Future year file: " Used Future Quarterly Peak Model Data Point.csv ." The format of all four of these model files is the same. The table below describes the variables in the Quarterly Peak Model Datafile. Output file name: "Scenario Name + (Used) Baseline/Future Quarterly Peak Model Data (Point)" Variable Description _id The ID is a unique identifier for each model grid cell. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) _type lat Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. long Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. date Year and Quarter (01= 1st quarter, 04= 2nd quarter, etc.) crustal Crustal PM nh4 Ammonium PM so4 Sulfate PM
ec Elemental Carbon no3 Nitrate PM

oc Organic carbon PM pm25 PM2.5 mass (only used to gradient adjust PM2.5 for gradient adjusted spatial fields) cm Coarse PM (ug/m3) (only used for visbility calculations)



## 7.1.4 Species Fractions Species fractions are simply the fraction of quarterly average PM2.5 at a given monitor attributable to seven (and potentially eight) species: nitrate (NO3), sulfate (SO4), organic carbon (OC), crustal, elemental carbon (EC), ammonium (NH4), and particle-bound water (PBW). (And pending data availability, an eighth species, salt, can be included as well, theDaily PM Analysis: Details

April 2014 Abt Associates Inc. 183 

### default MATS species files include salt data. But salt is an optional species on the model files. If base and future year modeled salt data is supplied, a salt RRF will be calculated. If there is no salt data in the model files, then the salt RRF will be set to 1.) When you check the Species Fractionsoption, you get a reusablefile with species fractions for each FRM monitor. Making the file reusable allows you to generate consistent results and, perhaps most importantly, allows the same file to be used by different MATS users.

7.1.4.1 Species Fractions Calculation After calculating the ambient level of SO4, NO3, OCMMB, EC, PBW, NH4, and crustal (as described in Step 2 of the Standard Analysis ), MATS then divides these ambient levels by the non-blank mass of PM2.5. To get non-blank PM2.5, MATS subtracts the blank mass from the FRM PM2.5 value. MATS then divides each of the species (except blank mass) by non-blank PM2.5. Example Calculation of Species Fractions The table below gives an example of theses calculations. The fraction is calculated by dividing mass (ug/m 3 

### ) by the Non-blank Mass. Note that salt is optional.
Units FRM PM2.5 Blank Mass Non-Bla nk Mass SO4 NO3 OCMM B EC PBW NH4 Crusta l (Salt)

Concentrati on 10.9175 0.5 10.4175 2.4160 1.1555 3.4847 0.2101 1.1555 1.2605 0.7353

-- Fraction 0.2319 0.1109 0.3345 0.0202 0.1109 0.1210 0.0706

--



### 7.1.4.2 Output Description The output file is named " Quarterly Peak Spec Frac Point.csv " with the Scenario Name appended at the beginning (e.g., " Example Daily PM Quarterly Peak Spec Frac Point.csv "). The table below describes the variables in the file. The interpolated variables (starting with i_xxx) are created when MATS is run, but are not needed when re-using a fractions file. They are also not needed when running with a user generated fractions file. Output file name: "Scenario Name + Quarterly Peak Spec Frac Point" Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _STATE_NAME State name. (This is a character variable.) _COUNTY_NAME County name. (This is a character variable.) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 184 monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_gridcell Identifier of grid cell closest to the monitor
quarter Quarter pm25_mass_frac PM2.5 mass used to calculate species fractions fcr Crustal fraction of PM2.5 mass fec Elemental carbon fraction of PM2.5 mass fnh4 Ammonium fraction of PM2.5 mass focm Organic carbon fraction of PM2.5 mass fso4 Sulfate ion fraction of PM2.5 mass fno3 Nitrate ion fraction of PM2.5 mass fwater Water fraction of PM2.5 mass fsalt Salt fraction of PM2.5 mass blank_mass Blank mass don Degree of neutralization of sulfate used to calculate ammonium mass (0.000 - 0.375) i_so4 Interpolated sulfate ion i_no3r Interpolated retained nitrate ion i_ocb Interpolated blank-adjusted organic carbon i_ec Interpolated elemental carbon i_crustal Interpolated crustal i_don Interpolated degree of neutralization of sulfate (DON). i_nh4 Interpolated ammonium i_no3 Interpolated nitrate ion (only used to calculate volatilized ammonium; if option is selected) i_salt Interpolated salt


### Note:

· i_ocb is only used to to calculate the OCMmb "floor".

· i_nh4 is not used if DON is used to calculate the ammonium concentration (and fraction).

· i_no3 is only used to calculate the "volatilized ammonium", if the option is selected (not used by default). 

## 7.2 Output Choice - Advanced
In the Output Choice Advancedwindow, MATS lets you choose various files grouped under the heading Miscellaneous Outputs . These files are generally used for QA and are described below.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 185 

## 7.2.1 Miscellaneous Outputs MATS gives you ability to generate a number of specialized files for quality assurance, identify the monitor in each county with the highest forecast, and other reasons. These files include:

· Daily files

. The MATS default is to output the 98th percentile design values, which are based on a weighted average of five years of data. However, checking this box will output more detailed calculations (the peak calculations are the basis of all of the design value calculations). There are two daily files. The first contains data for years, quarters and days, and containsbaseline PM2.5 and species concentrations, RRFs, forecasted PM2.5 and species concentrations. The "true" RRFs and PM2.5 and species concentrations are found in this file. A second file has the 98th percentile PM2.5 value in the baseline and future for each year at each monitor. Both of these daily files are important because all of the basic PM2.5 calculations in MATS occur on a daily basis.

· High county sites

. The MATS default is to output the point results for all FRM sites. Checking this box will also create a file which contains only the single highest monitor in each county (based on the highest future-year value). This dataset is a subset of the all sites file.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 186 

### · Quarterly average speciated monitors

. This file contains the raw quarterly peak speciated data at STN and IMPROVE sites that MATS uses to do interpolations (to calculate species fractions). This is the subset of species data that MATS uses for each particular scenario (based on the MATS inputs and configuration settings).

· Design value periods

. This file contains standard MATS output for each individual design value period within the period covered by the analysis.

· Neighbor files

. The neighbor files contain the “nearest neighbor” data for the VNA interpolation scheme. The data includes the distance to neighbor monitors and weights used to do the interpolations. There is information for each FRM monitor for each quarter and for each species.

7.2.1.1 Daily Files The Daily Files provide intermediate calculations performed by MATS. There are two files generated by checking this option:

· " Daily All Years All Days PM25 Point ". This file has baseline and future values for PM2.5 Top 32 ranked values and constituent species. In addition it gives the speciated RRFs.

· " Daily All Years High Days PM25 Point ". This file identifies the 98th percentile PM2.5 value in the baseline and future for each year at each monitor. Note that the baseline and future quarters and days may differ. When generating these files, MATS appends the Scenario Nameat the beginning (e.g., " Example Daily PM Daily All Years All Days PM25 Point.csv "). The variables in each file are described below. Output file name: "Scenario Name + Daily All Years All Days PM25 Point" Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _type FRM data _STATE_NAME State name. (This is a character variable.) _COUNTY_NAME County name. (This is a character variable.) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_gridcell Identifier of grid cell closest to the monitor day Day (yyyymmdd) year Year (up to 5 years)Daily PM Analysis: Details

April 2014 Abt Associates Inc. 187 quarter Quarter b_pm25_d_conc Base year top PM2.5 concentrations f_pm25_d_conc Future year top PM2.5 concentrations b_blank_mass Base year blank mass concentration (ug/m3) b_crustal_mass Base year crustal mass concentration (ug/m3) b_EC_mass Base year elemental carbon mass concentration (ug/m3) b_NH4_mass Base year ammonium mass concentration (ug/m3) b_Ocmb_mass Base year organic carbon mass (by difference) concentration (ug/m3) b_SO4_mass Base year sulfate ion mass concentration (ug/m3) b_NO3_mass Base year nitrate ion mass concentration (ug/m3) b_water_mass Base year water mass concentration (ug/m3) b_salt_mass Base year salt mass concentration (ug/m3) f_blank_mass Future year blank mass concentration (ug/m3) f_crustal_mass Future year crustal mass concentration (ug/m3) f_EC_mass Future year elemental carbon mass concentration (ug/m3) f_NH4_mass Future year ammonium mass concentration (ug/m3) f_Ocmb_mass Future year organic carbon mass (by difference) concentration (ug/m3) f_SO4_mass Future year sulfate ion mass concentration (ug/m3) f_NO3_mass Future year nitrate ion mass concentration (ug/m3) f_water_mass Future year water mass concentration (ug/m3) f_salt_mass Future year salt mass concentration (ug/m3) rrf_crustal_q Relative response factor- Crusatal Mass rrf_ec_q Relative response factor- Elemental Carbon Mass rrf_nh4_q Relative response factor- Ammonium Mass. (Not used if future year ammonium is calculated using base year DON values) rrf_oc_q Relative response factor- Organic Carbon Mass rrf_so4_q Relative response factor- Sulfate Mass rrf_no3_q Relative response factor- Nitrate Mass rrf_water_q Relative response factor- Water Mass rrf_salt_q Relative response factor- Salt Mass Output file name: "Scenario Name + Daily All Years High Days PM25 Point" Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _type FRM data _STATE_NAME State name. (This is a character variable.) _COUNTY_NAME County name. (This is a character variable.)Daily PM Analysis: Details

April 2014 Abt Associates Inc. 188 monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_gridcell Identifier of grid cell closest to the monitor 98th_percent_rank year Year (up to 5 years) date_b Base date b_high_quarter Base high quarter number b_pm25_d_conc Base year peak (98th percentile) PM2.5 concentration date_f Future date f_high_quarter Future high quarter number f_pm25_d_conc Future year peak (98th percentile) PM2.5 concentration f_blank_mass Future year blank mass concentration for high days (ug/m3) f_crustal_mass Future year crustal mass concentration for high days (ug/m3) f_EC_mass Future year elemental carbon mass concentration for high days (ug/m3) f_NH4_mass Future year ammonium mass concentration for high days (ug/m3) f_Ocmb_mass Future year organic carbon mass (by difference) concentration for high days (ug/m3) f_SO4_mass Future year sulfate ion mass concentration for high days (ug/m3) f_NO3_mass Future year nitrate ion mass concentration for high days (ug/m3) f_water_mass Future year water mass concentration for high days (ug/m3) f_salt_mass Future year salt mass concentration for high days (ug/m3) rrf_crustal_q Relative response factor for high days - Crusatal Mass rrf_ec_q Relative response factor for high days - Elemental Carbon Mass rrf_nh4_q Relative response factor for high days - Ammonium Mass. (Not used if future year ammonium is calculated using base year DON values) rrf_oc_q Relative response factor for high days - Organic Carbon Mass rrf_so4_q Relative response factor for high days - Sulfate Mass rrf_no3_q Relative response factor for high days - Nitrate Mass rrf_water_q Relative response factor for high days - Water Mass rrf_salt_q Relative response factor for high days - Salt MassDaily PM Analysis: Details

April 2014 Abt Associates Inc. 189 

### 7.2.1.2 Output Description - High County Sites In this file, MATS reports the monitor with the highest forecasted peak PM2.5 design value in each county. The name of this file is " High County Sites " with the Scenario Nameappended at the beginning (e.g., " Example Daily PM -- High County Sites.csv "). The table below describes the variables in the output file. "Scenario Name + High County Sites" Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _type FRM data _STATE_NAME State name. (This is a character variable.) _COUNTY_NAME County name. (This is a character variable.) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_gridcell Identifier of grid cell closest to the monitor b_pm25_d_DV Base year 5 year weighted average PM2.5 24-hr average (daily) design value f_pm25_d_DV Future year 5 year weighted average PM2.5 24-hr average (daily) design value b_blank_mass Base year blank mass concentration (ug/m3) b_crustal_mass Base year crustal mass concentration (ug/m3) b_EC_mass Base year elemental carbon mass concentration (ug/m3) b_NH4_mass Base year ammonium mass concentration (ug/m3) b_Ocmb_mass Base year organic carbon mass (by difference) concentration (ug/m3) b_SO4_mass Base year sulfate ion mass concentration (ug/m3) b_NO3_mass Base year nitrate ion mass concentration (ug/m3) b_water_mass Base year water mass concentration (ug/m3) b_salt_mass Base year salt mass concentration (ug/m3) f_blank_mass Future year blank mass concentration (ug/m3) f_crustal_mass Future year crustal mass concentration (ug/m3) f_EC_mass Future year elemental carbon mass concentration (ug/m3) f_NH4_mass Future year ammonium mass concentration (ug/m3) f_Ocmb_mass Future year organic carbon mass (by difference) concentration (ug/m3) f_SO4_mass Future year sulfate ion mass concentration (ug/m3) f_NO3_mass Future year nitrate ion mass concentration (ug/m3) f_water_mass Future year water mass concentration (ug/m3) f_salt_mass Future year salt mass concentration (ug/m3) rrf_crustal Resultant annual relative response factor- Crustal MassDaily PM Analysis: Details

April 2014 Abt Associates Inc. 190 rrf_ec Resultant annual response factor- Elemental Carbon Mass rrf_nh4 Resultant annual relative response factor- Ammonium Mass. rrf_oc Resultant annual relative response factor- Organic Carbon Mass rrf_so4 Resultant annual relative response factor- Sulfate Mass rrf_no3 Resultant annual relative response factor- Nitrate Mass rrf_water_mass Resultant annual relative response factor- Water Mass rrf_salt Resultant annual relative response factor- Salt Mass (set equal to 1 if modeled salt is not used)


### 7.2.1.3 Design Value Periods Normally, MATS will output one set of files covering the entire analysis period specified by the user. The outputs represent the averages of the values for each 3-year design value period. If the "Output design value periods" option is checked, MATS will produce discrete outputs for each design value period. The output files will be the same as a standard analysis, but with "Period 1", "Period 2", etc., attached at the end of the name. Please note, however, that checking this option will substantially increase the MATS run time, by up to four times.

7.2.1.4 Output Description - Quarterly Average Speciated Monitors In this file, MATS reports the quarterly peak values at the speciated monitors. The speciated data is split into two files:

· " Quarterly Peak Speciated Monitors ". This has crustal, EC, OC, SO4, NO3, retained NO3, and salt quarterly peak speciated values.

· " Quarterly Peak NH4_DON Monitors ". This has NH4 and DON quarterly peak speciated values. MATS generates these files with the Scenario Nameappended at the beginning (e.g., " Example Daily PM Quarterly Peak Speciated Monitors.csv "). The tables below describe the variables in each file. Output file name: "Scenario Name + Quarterly Peak Speciated Monitors" Variable Description _id IMPROVE/STN Site Code _type Monitor type (e.g., STN) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_gridcell Identifier of grid cell closest to the monitor quarter QuarterDaily PM Analysis: Details

April 2014 Abt Associates Inc. 191 b_crustal_mass Base year crustal mass concentration (ug/m3) b_EC_mass Base year elemental carbon mass concentration (ug/m3) b_OCB_mass Base year organic carbon mass blank adjusted (ug/m3) b_SO4_mass Base year sulfate ion mass concentration (ug/m3) b_NO3_mass Base year nitrate ion mass concentration (ug/m3) b_no3r_mass Base year retained nitrate ion mass concentration (ug/m3) b_salt_mass Base year salt mass concentration (ug/m3) Output file name: "Scenario Name + Quarterly Peak NH4 & DON Monitors" Variable Description _id IMPROVE/STN Site Code _type Monitor type (e.g., STN) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_gridcell Identifier of grid cell closest to the monitor quarter Quarter b_NH4_mass Base year ammonium mass concentration (ug/m3) b_DON Base year degree of neutralization (DON)



### 7.2.1.5 Neighbor Files MATS calculates the nearby monitors or "neighbors" separately for each species when interpolating to FRM monitors ("points"). In this file, MATS reports the neighbors involved in interpolating species values to the FRM monitor sites. The name of this file is "Neighbor File Point " with the Scenario Nameappended at the beginning (e.g., " Example Daily PM Neighbor File Point.csv "). The table below describes the variables in the output file. Output file name: "Scenario Name + Neighbor File Point" Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _state_name State name. (This is a character variable.) _county_name County name. (This is a character variable.) monitor_lat Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. monitor_long Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 192 monitor_gridcell Identifier of grid cell closest to the monitor quarter Quarter _neighbor IMPROVE/STN Site Code. (This is a character variable.) neighbor_gridcell Identifier of grid cell closest to the neighbor distance Distance in kilometers from FRM monitor site and IMPROVE/STN/SPECTRE neighbor. weightdistance Inverse-distance weight weightdistancesquared Inverse-distance-squared weight pollutant Pollutant (e.g., SO4). Note interpolation approach can vary by pollutant


## 7.3 Data Input
In the Data Inputwindow, you specify the MATS input files that are used in each scenario. There are three main types of files which must be specified. These include ambient PM2.5 species data (STN and IMPROVE), ambient total PM2.5 data (FRM and IMPROVE), and gridded model output data (e.g. CMAQ or CAMx data). There is specific terminology that is used on the Data Input page. "Official" data refers to PM2.5 FRM data that can be used to determine official design values for compliance purposes (comparison to the NAAQS). Other datasets which may not have rigid regulatory significance are sometimes referred to as "unofficial" data. The individual input file choices are explained below.



## Species Data

. MATS needs ambient PM2.5 species data to calculate speciesDaily PM Analysis: Details

April 2014 Abt Associates Inc. 193 

### concentrations at FRM monitoring sites. Users have a choice of supplying a “Species Monitor Data File” or a “Species Fractions File”.

· Species Monitor Data File . The default is to provide a species monitor data file. MATS is populated with daily average species data from STN and IMPROVE sites across the country. However, users can also provide their own ambient data file. MATS uses the daily average species data to calculate species fractions at each FRM monitor. The species fraction data is combined with the “unofficial daily average PM2.5 data” to calculate species concentrations. The default MATS species data file contains all available data. However, there is a data flag to indicate site days that are recommended to be removed from the species fractions calculations. This is not necessarily the same data flags that have been identified by State agencies. MATS has incorporated flagging routines that remove data that are considered to be outliers and/or incomplete data. (A description of the flags is provided in the section on Species Fractions Calculation Options .)

· Species Fraction File

. Alternatively, the user can choose to use a pre-calculated species fractions file which contains quarterly species information for the FRM monitors of interest. MATS can also re-use a species fractions file that has previously been generated by MATS. To re-use a previously created fractions file, simply supply the correct path to the file. (The calculation of species fractions is discussed here .)


## PM2.5 Monitor Data

. MATS uses both "official" and "unofficial" data in its calculations

.

· Unofficial Daily Average PM2.5 Data File

. The “unofficial daily average PM2.5” file contains the PM2.5 data that is needed to calculate species fractions. It is used in combination with the “species monitor data file” from above. The unofficial daily average PM2.5 file is not needed if the user supplies a pre-calculated species fractions file. Similar to the species monitor data file from above, the “unofficial” PM2.5 data file contains a data flag to indicate site days that are recommended to be removed from the species fractions calculations. The flagged data is matched between the species file and the PM2.5 file so that the same site days are removed. However, the PM2.5 data file contains additional data (sites that don ’ t contain speciation measurements) and therefore has additional flagged site days. These are not the same data flags that have been identified by State agencies. MATS has incorporated flagging routines that remove data that are considered to be outliers and/or incomplete data. (A description of the flags is provided in the section on Species Fractions Calculation Options .) The user is free to unflag existing data or add flags as necessary and appropriate.

· Official Daily Average FRM Data File

. The “official daily average file” contains all of the “official” daily FRM data that has been used to calculate daily PM2.5 design values. It is used to calculate design values and 5 year weighted-average design values as part of the attainment test.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 194 

### The default data file in MATS was created by the Air Quality Analysis Group within OAQPS. In most cases, the data should not be altered, however in some cases (e.g. sensitivity analyses) there may be a need to add or remove data.


## Model Data . The “model data” refers to gridded model output from models such as CMAQ or CAMx. The user can choose either daily model data input or quarterly model data input (which would be quarterly peak values calculated from the daily model data). Either will work. The default setting is daily average data. Recall that MATS can generate quarterly peak model data (which can then be re-used in subsequent MATS runs). Model data must be selected for all MATS runs. The size of the modeling grid defines the outputs for point estimates. For point estimates, MATS will output the results for all specified monitors within the domain. Note that you need to specify both a Baseline Fileand a Forecast File . The baseline file should be consistent with the historical monitor data that you use, and the forecast year is the future-year of interest. 

## 7.3.1 Species Data Input The species data may be in form of monitor data (specified below) that MATS then uses to calculate species fractions, or it may be in the form of species fractions directly ( specified here ). Monitor data should be in the form of a simple text file. The first row specifies the frequency of the data ( e.g ., day). The second row presents comma-separated variable names. The third row begins the data values. Below is an example of the monitor data file format and descriptions of the variables in the file.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 195 

### Format of Speciated Monitor Data

Speciated Monitor Data Variable Descriptions
Variable Description _id The ID is a unique name for each monitor in a particular location. (This is a character variable.) LAT Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. LONG Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. _TYPE STN or IMPROVE network data DATE Date of daily average ambient data with YYYYMMDD format (This is a numeric variable) SO4 Measured sulfate ion NO3R Estimated nitrate retained on FRM filter, using measured nitrate, hourly T and RH NH4 Measured NH4+ ion OCB OC blank adjusted, STN uses constant blank value per sampler type, IMPROVE uses backup filter methodology EC Measured EC CRUSTAL Using IMPROVE algorithm, Crustal, aka "Fine Soil" = 2.2 ×[Al] + 2.49 ×[Si] + 1.63 ×[Ca] + 2.42 ×[Fe] + 1.94 ×[Ti] SALT Estimated salt using Cl (Salt=1.8*Cl), where Cl is elemental chloride DON Degree of neutralization of SO4 (0-0.375)Daily PM Analysis: Details

April 2014 Abt Associates Inc. 196 H2O_AIM Calculated water using AIM and measured SO4, adjusted NO3 and measured NH4 OC Measured OC NO3 Measured nitrate ion SO4_3S Sulfate value derived from S, as per IMPROVE protocol. i.e. SO4_3S = 3*S. CRUSTAL_ALT Alternative Crustal calculation using measured Si, Fe, Ca, Ti (modified formula without Al) = 3.73 ×[Si] + 1.63 ×[Ca] + 2.42 ×[Fe] + 1.94 ×[Ti] FRM_MASS FRM mass MEASURED_FM STN or IMPROVE sampler measured fine mass (Teflon filter) RCFM Reconstructed Fine Mass using IMPROVE protocol, RCFM = [Amm_Sulfate] + [Amm_Nitrate] + [OCM] + [EC] + [Fine Soil] Al Measured Al Ca Measured Ca Fe Measured Fe Ti Measured Ti Si Measured Si EPA_FLAG Flag to indicate data that EPA recommends to be removed from the species fractions calculations. 0 = valid data, 1 or greater = data that has been flagged and should be removed USER_FLAG Flag to indicate additional data that the user wants to remove from the species fractions calculations. 0 = valid data, 1 or greater = data that has been flagged and should be removed 

### Note: Some variables are supplied for QA purposes only and are either not used by MATS or are calculated internally by MATS. For example, "OC" is not used by MATS (OCb is used) and H20_AIM is calculated internally. Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.)


## 7.3.2 PM2.5 Monitor Data Input MATS uses the "unofficial" daily PM2.5 file for the calculation of species fractions files. MATS uses the "official" daily PM2.5 file for point estimates.
7.3.2.1 Unofficial Daily PM2.5 Monitor Data Input Monitor data should be in the form of a simple text file. The first row specifies the frequency of the data ( e.g ., day). The second row presents comma-separated variable names. The third row begins the data values. Below is an example of the monitor data file format and descriptions of the variables in the file.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 197 

### Format of Unofficial Daily PM2.5 Monitor Data

Unofficial Daily PM2.5 Monitor Data Variable Descriptions
Variable Description _ID The ID is a unique name for each monitor in a particular location. (This is a character variable.) _TYPE FRM or IMPROVE data. (This is a character variable.) LAT Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. LONG Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. DATE Date of daily average ambient data with YYYYMMDD format (This is a numeric variable) PM25 Measured PM2.5 mass (ug/m3) EPA_FLAG Flag to indicate data that EPA recommends to be removed from the species fractions calculations. 0 = valid data, 1 = data that has been flagged and should be removed USER_FLAG Flag to indicate additional data that the user wants to remove from the species fractions calculations. 0 = valid data, 1 or greater = data that has been flagged and should be removed. 

### Note: Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.)Daily PM Analysis: Details

April 2014 Abt Associates Inc. 198 

### 7.3.2.2 Official Daily PM2.5 Monitor Data Input Monitor data should be in the form of a simple text file. The first row specifies the frequency of the data ( e.g ., day). The second row presents comma-separated variable names. The third row begins the data values. Below is an example of the monitor data file format and descriptions of the variables in the file. Format of Official Daily PM2.5 Monitor Data

Official Daily PM2.5 Monitor Data Variable Descriptions
Variable Description _ID The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _TYPE FRM data MONTIOR_LAT Latitude at the monitor site in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. MONITOR_LONG Longitude at the monitor site in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. DATE Date of daily average ambient data with YYYYMMDD format (This is a numeric variable) PM25 Measured PM2.5 mass (ug/m3) 98_PERCENTILE Official 98th percentile values for each site for each year are identified by a flag = "1"Daily PM Analysis: Details

April 2014 Abt Associates Inc. 199 EPA_FLAG Official flags to indicate data that has been removed from design value calculations. 0 = valid data, 1 = data that has been flagged and removed USER_FLAG Flag to indicate additional data that the user wants to remove from design value calculations. 0 = valid data, 1 = data that has been flagged and should be removed. COMPLETION_COD E Official design value completion codes (1, 2, 3, 4, 5, and -9). Codes are valid for the end year of each 3 year design value period. _STATE_NAME State name. (This is a character variable.) _COUNTY_NAME County name. (This is a character variable.) RANK_98 Rank order of the official 98th percentile measured value for the year (single value for each site year). 

### Note: Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.)


## 7.3.3 Model Data Input Model data should be in the form of a simple text file. The first row specifies the frequency of the data ( e.g ., day). The second row presents comma-separated variable names. The third row begins the data values. Below is an example of the model data file format and descriptions of the variables in the file. Note that there is both a base year and a future year model file. The format for both is the same. Note that you can load in either daily model data or quarterly model data.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 200 

### Format of Model Data

Model Data Variable Descriptions
Variable Description _ID The ID is a unique value for each model grid cell. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) _TYPE Leave blank LAT Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. LONG Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. DATE Date of daily average model value with YYYYMMDD format (This is a numeric variable) Crustal Crustal PM2.5 mass NH4 Ammonium mass SO4 Sulfate PM EC Elemental carbon NO3 Nitrate PM OC Organic mass PM PM25 PM2.5 mass CM Coarse PM mass (ug/m3) SALT Salt (Optional) 

### Note:Daily PM Analysis: Details

April 2014 Abt Associates Inc. 201 

### · The "PM25" mass variable is used to sort the model data to determine the "peak" modeled PM2.5 days for the RRF calculations (based on the high base year PM2.5 concentrations). It is up to the user to provide a modeled PM2.5 mass concentration using an appropriate definition of modeled PM2.5 mass.

· Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.) 

## 7.4 Species Fractions Calculation Options
The Species Fractions Calculation Optionshas two main sections. One involving speciated monitor data (e.g., STN and IMPROVE monitors) and the other total PM2.5 monitor data (FRM and IMPROVE). For each type of data you can specify the years of interest , whether you want to delete certain data , and the minimum amount of datafor a monitor to be considered "valid" (and thus included in the calculations). In the next sections, we describe each of these three options in more detail. Note that these options apply more or less in the same way for both speciated monitor data and total PM2.5 monitor data. Also note that these options are no longer relevant if you have loaded a species fractions file

.

· IMPROVE-STN Monitor Data . The speciation data from STN and IMPROVE monitors are interpolated by MATS in order to provide species data for any point in a modeling domain. The interpolated species data is used to calculate species fractions at FRM monitors. Note that you do notneed to have values for all species for a monitor to be considered valid, as each species is considered individually. However, the "EPA_Flag" variable in the default "species for fractions" file has been set so that all monitor days that do not have complete species data are not used in the calculations (flag = 1). If the user wants to use the incomplete species data, the flag can changed to "0".

· PM2.5 Monitor Data . The total PM2.5 data from FRM are used by MATS to calculate species fractions (in conjunction with the interpolated speciation data from STN and IMPROVE monitors).Daily PM Analysis: Details

April 2014 Abt Associates Inc. 202 

## 7.4.1 Monitor Data Years Using the Start Yearand End Yeardrop-down menu options, you can choose more than one year of speciated data for the calculation of species fractions. The default approach in MATS is to use three years of data.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 203 

### MATS handles multiple years of data by calculating averages for each species by quarter and year. MATS then averages the quarterly values across the years (e.g., average quarter 1 values of SO4 across two years to get a single "quarter 1" estimate). For example, if for 2006-2008 we have SO4 averages of peak values in quarter 1 of 8.2 ug/m 3 

### (for 2006), 6.2 ug/m 3 

### (for 2007), and3.6 ug/m 3 

### (for 2008), then the average across the years would equal 6.0 (=[8.2+6.2+3.6]/3). After completing this step, MATS will have four quarterly estimates for each species at each speciated monitor. These quarterly values are then ready to be interpolated to FRM sites.


## 7.4.2 Delete Specifed Data Values The default is to delete the observations specified by EPA. (That is, these observations are excluded from a particular analysis, while they of course remain in the database.) As described in the Data Inputsection, valid data are given a value of "0" and observations that are deleted are given a value of "1" to "10", as follows: 0. Data is OK to use 1. Important species is missing (e.g. no3, so4, oc, etc) 2. Constructed mass < 30% total mass 3. Constructed mass > 2 times total mass 4. Fire event 5. total mass < so4 6. total mass < crustal 7. OC is outside QA criteria 8. Soil is outside QA criteria 9. Both OC and soil are outside QA criteria 10. Regional concurrence on exceptional event

There is alsoan option for the user to flag data, using the same convention of "0" for valid data and "1" to "10" for data marked for deletion. If both the EPA-specifiedand Userspecifiedflags are checked, then MATS deletes any observations that are marked for deletion by either the EPA or the user. This makes it easy for the user to flag additional data for removal from the calculations (without deleting the actual record from the ambient data file).



## 7.4.3 Minimum Data Requirements There are three sets of minimum data requirements:Daily PM Analysis: Details

April 2014 Abt Associates Inc. 204 

### · Minimum number of valid days per quarter
. This is the minimum number of site-days per valid quarter. The default is 11 days, which corresponds to > 75% completeness for monitors on a 1 in 6 day schedule. This is a minimum number of samples that is routinely used in calculations of quarterly average concentrations.

· Minimum number of valid quarters per valid year
. This is the number of valid quarters of data required for a given year. The default value is 1 quarter. If the value is set = 2, then there will need to be 2 quarters of valid data for a given year to be valid.

· Minimum number of valid years required for valid monitor
. This is the number of valid years that are needed in order for a particular monitor's data to be considered valid. The default is 1 for IMPROVE-STN monitor data and the range is 1-4.

Example 1: Minimum Days = 11, Minimum Quarters = 1, Minimum Years = 1 Consider the default assumptions and the following number of observations from three monitors:
Monitor 1 Monitor 2 Monitor 3 Year Quarter # Obs. # Obs. # Obs. 2006 1 8 11 11 2 6 13 8 3 11 4 12 4 5 12 8 2007 1 11 10 9 2 9 11 12 3 12 13 10 4 6 12 9 2008 1 6 15 12 2 7 11 10 3 12 12 10 4 13 9 12 

### With the default 11 minimum days required, MATS would then consider the highlighted quarters (above) as valid. MATS would then use all of the highlighted quarters as all of the following years are valid.
Monitor 1 Monitor 2 Monitor 3 Year Avg (ug/m 3 ) Avg (ug/m 3 ) Avg (ug/m 3 ) 2006 v v v 2007 v v v 2008 v v vDaily PM Analysis: Details

April 2014 Abt Associates Inc. 205 

### Example 2: Minimum Days = 11, Minimum Quarters = 2, Minimum Years = 2 Consider the data from three monitors in the previous examples: Minimum Days = 11, Minimum Quarters = 2, Minimum Years = 2 Monitor 1 Monitor 2 Monitor 3 Year Quarter # Obs. # Obs. # Obs. 2006 1 8 11 11 2 6 13 8 3 11 4 12 4 5 12 8 2007 1 11 10 9 2 9 11 12 3 12 13 10 4 6 12 9 2008 1 6 15 12 2 7 11 10 3 12 12 10 4 13 9 12 

### With the default 11 minimum days required, MATS would then consider the highlighted quarters (above) as valid. MATS would then use only a subset of the highlighted quarters, as not all of the years are valid. Monitor 1 would not be used at all, and data from Monitor 3 would only be used from 2006 and 2008.
Monitor 1 Monitor 2 Monitor 3 Year Avg (ug/m 3 ) Avg (ug/m 3 ) Avg (ug/m 3 ) 2006

-- v v 2007

-- v -- 2008

-- v v 

## 7.5 Species Fractions Calculation Options - Advanced
The Species Fractions Calculation Options - Advancedscreen allows you to make relatively advanced choices for your analysis. Generally speaking, the default options settings are consistent with the EPA modeling guidance document. The first set of options lets you specify which monitor data you want to use. The second set of options allows you to specify the interpolation weighting that you want to use and whether the interpolation involves a maximum distance or not. The third set of options involves choices regarding ammonium, blank mass, and organic carbon.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 206 

## 7.5.1 Using Monitor Data to Calculate Species Fractions The Using Monitor Data to Calculate Species Fractionspanel allows you to choose how you will choose IMPROVE and STN speciated monitor data and ("unofficial") PM2.5 monitor data to calculate quarterly peak values. There are three options:

· Use Top X Percent of Daily Monitor Days . MATS chooses the top "X" percent of days per quarter that you specify and averages them.

· Use All Daily Monitor Values Greater than Fixed Amount (ug/m 3 

### ) . MATS chooses all monitor values greater than or equal to a fixed amount that you specify and averages them. Note that you also need to specify a minimum number of days greater than orDaily PM Analysis: Details

April 2014 Abt Associates Inc. 207 

### equal to your specified amount. If there are an insufficient number of days then MATS drops the data for that particular quarter.

· Use Top X Number of Daily Monitor Days . MATS chooses the top "X" number of days per quarter that you specify and averages them. These three options work in essentially the same way for IMPROVE and STN speciated monitor data and for ("unofficial") PM2.5 monitor data. Below are some examples of how these options work. Note that the IMPROVE and STN speciated monitor data uses the "measured_FM" variable to identify peak days. Note also that it is possible that the option used to identify peak days (e.g., Use Top X Percent of Daily Monitor Days) does not give a unique set of days because a number of days may have the same value (see Example 1, below).

Example 1: Use Top 10 Percent of Daily Monitor Days Assume the default of using the top 10 percent of days. Let's say there are 27 days in the first quarter (January-March) at a particular monitor for a given year, and 24, 25, and 32 valid days of data in quarters 2,3, and 4. MATS will then calculate the number of peak days in each quarter as follows: Year 2006, Q1: round(0.10*27) = round(2.7) = 3 Year 2006, Q2: round(0.10*24) = round(2.4) = 2 Year 2006, Q3: round(0.10*25) = round(2.5) = 3 Year 2006, Q4: round(0.10*32) = round(3.2) = 3. In the sample data for quarter 1 (below), there are not three unique peak days because theDaily PM Analysis: Details

April 2014 Abt Associates Inc. 208 

### third and fourth highest days (highlighted in yellow) have the same value. In this case, MATS uses the top 4 days. Sample Data for Quarter 1 - Highlighted Top 10 Percent Day measured_FM 1 13.9 2 13.8 3 13.6 4 13.6 5 13.0 6 12.6 7 12.6 8 12.4 9 12.1 10 11.7 11 11.4 12 10.4 13 10.2 14 10.1 15 9.6 16 9.5 17 9.4 18 9.0 19 8.9 20 8.4 21 8.2 22 8.2 23 7.6 24 7.4 25 7.3 26 6.6 27 6.6 

### Example 2: Use All Daily Monitor Values Greater than 13 ug/m 3 

### With the same sample data and with the choice to use monitor values greater than 13 ug/m 3 

### , MATS will select the top five days. Note that if you had selected values greater than 14 ug/m 3 

### , MATS would not have any data and would have dropped this quarter. Sample Data for Quarter 1 - Highlighted Greater than or Equal to 13 ug/m 3 Day measured_FM 1 13.9 2 13.8 3 13.6 4 13.6 5 13.0 6 12.6 7 12.6 8 12.4 9 12.1 10 11.7 11 11.4 12 10.4Daily PM Analysis: Details

April 2014 Abt Associates Inc. 209 13 10.2 14 10.1 15 9.6 16 9.5 17 9.4 18 9.0 19 8.9 20 8.4 21 8.2 22 8.2 23 7.6 24 7.4 25 7.3 26 6.6 27 6.6 

### Example 3: Use Top 3 Daily Monitor Days With the same sample data and with the choice to use the top three monitor days, MATS would select the top four days, because the third and fourth days have the same value. This is the same result as in Example 1 (above).


## 7.5.2 Interpolation Options for Species Fractions Calculation The Interpolation Optionspanel allows you to choose how you will interpolate , or combine, the values from different monitors. One approach is to use Inverse Distance Weights . This means that the weight given to any particular monitor is inversely proportional to its distance from the point of interest. A second approach is Inverse Distance Squared Weights, which means that the weights are inversely proportional to the square of the distance. And the third approach is Equal Weighting of Monitors. The default approach for PM is Inverse Distance Squared Weights.

When interpolating monitor values, MATS allows you to identify the monitors you want to use based on their distance away from the point of interest ( e.g. , the center of a grid cell). The first step in the interpolation process is to identify the monitors that are nearby, or neighbors, for each point of interest. The next step is to determine the distance ( in kilometers ) from the nearby monitors to the point of interest. The default approach is to include all valid monitors ( i.e. , those that satisfy the three criteria in the Species Fractions Calculation Options panel), regardless of distance. If youDaily PM Analysis: Details

April 2014 Abt Associates Inc. 210 

### want to limit the use of monitors based on distance, type in the distance you want to use (e.g., 100) next to the pollutant of interest.

You can also change the number using the arrows. The double arrow on the right increases the number in units of 100:

and the double arrow on the left decreases the number in units of 100. The upper arrow increases the number in single digits:

and the lower arrow reduces the number in single digits. Note that a distance of one hundred (100) kilometers means that any monitors further than 100 kilometers can no longer be used in the interpolation. If a point of interest has no monitors within the specified distance, then no value is calculated.


## 7.5.3 Miscellaneous Options The Miscellaneous Options panel lets you make choices regarding:

· Ammonium . This allows you to specify whether MATS uses degree of neutralization (DON) values to calculate ammonium (NH4) or whether it uses measured ammonium in conjunction with an assumption about the percentage of NH4 that evaporates. The default option is to use DON values. If you want to use measured ammonium, you need to click the button and choose a NH4 percentage evaporating (e.g., 50). The default is "0", which assumes that no ammonium evaporates from the FRM filters. The calculations underlying the default and alternative ammonium calculations are discussed in detail in the section on species fractions calculations

.

· Default Blank Mass . The Default Blank Mass option simply allows you to set default blank mass to the desired level. The default is 0.5. You can type desired value, or use the arrows to increase or decrease the value.

· Organic Carbon . This allows you to set the "floor" and the "ceiling" for the mass balance calculation for organic carbon. The calculations involved are discussed in detailDaily PM Analysis: Details

April 2014 Abt Associates Inc. 211 

### in the section on species fractions calculations

.



## 7.5.4 Internal Precision of the Calculations All calculations in MATS are carried out with single precision. In addition, most output files by default generate outputs only up to 3 digits after the decimal. Therefore, the base year DV (b_pm25_d_q_DV) may differ slightly from the sum of the component species of the quarterly PM2.5 MATS output files. In particular, the water calculation requires additional precision in the species fractions. It is therefore recommended to have at least seven decimal digits in the species fractions. This may be accomplished by increasing precision of the species and species fractions calculations to 7 (or more) significant digits by modifying the MATS.ini file as follows: set species_calc_precision=7 and species_fraction_precision=7. Please note that the future year species always add up to the future year DV. However, increases in species fractions precision may result in very small changes in future DV due to the dependence of the future concentrations on the base year concentrations. 

## 7.6 PM2.5 Calculation Options
The PM2.5 Calculation Optionswindow allows you to specify the particular years of monitor data that you want to use from the input file you specified in the Data Input section. You can also specify the following:

· Valid FRM Monitors . You can specify the minimum number of design values (the default is 1) and whether you want to make sure that particular design values have to be used in the calculations.

· NH4 Future Calculation . You can also specify how you want to forecast NH4 values. The default approach is to use baseline DON values, and the alternative is to use baseline NH4 and a RRF value for NH4. (These calculations are described in detail here .)Daily PM Analysis: Details

April 2014 Abt Associates Inc. 212 

## 7.6.1 PM2.5 Monitor Data Years Using the Start Yearand End Yeardrop-down menu options, you can choose more than one year of official PM monitor data for the calculation of future PM2.5 values. The default approach in MATS is to use five years of data.



## 7.6.2 Valid FRM Monitors By default, MATS assumes that there only needs to be one design value for a monitor to be considered valid. In addition, MATS assumes that no particular design value is required, so different monitors with different years of data could be used. For example, if you specify the start year and end year as 2005 and 2009 (giving potential design values of 2005-2007, 2006-2008, and 2007-2009), then one monitor could have data for, say, 2005-2007 and another monitor data for 2006-2008, and both monitors would be used.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 213 

## 7.6.3 NH4 Future Calculation As described in the section on Forecasted Species Calculation , MATS can forecast NH4 using two different approaches. The default approach is to use base year DON values.



## 7.7 Model Data Options
The Model Data Optionssection allows you to specify:

· Temporal Adjustment at Monitor. This option specifies how many model grid cells to use in the calculation of RRFs for point estimates and for spatial estimates. Using the drop-down menu, y ou can choose 1x1, 3x3, 5,x5, and 7x7. (The default for a 12 kilometer by 12 kilometer grid is to use a 1x1 set of grid cells. The choice of grid size is discussed in the following EPA guidance: http://www.epa.gov/scram001/guidance/guide/final-03-pm-rh-guidance.pdf ) For PM analyses, MATS calculates meanconcentrations across the grid cell array (as compared to maximum concentrations used for ozone analyses).

· Advanced Options: RRF Model Values Used . This option allows you to choose three different ways to calculate quarterly peak modeled values: (1) the top X percent of daily model days, (2) all daily model values greater than or equal to a specified amount, and (3) the top X number of model days. (These three options are described in detail in Species Fractions Calculation Options - Advancedsection.) The peak modeled days are determined by sorting the PM2.5 variable in the baseline model data input file.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 214 

## 7.8 Final Check
The Final Checkwindow verifies the selections that you have made.Daily PM Analysis: Details

April 2014 Abt Associates Inc. 215 

### Click the button Press here to verify your selections . If there are any errors, MATS will present a message letting you know. For example, if the path to a model file is invalid -- perhaps you misspelled the file name -- you would get the following error:

After making the necessary correction, click the button Press here to verify your selections . Then click the Finishbutton.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 216 

## 8 

# Ozone Analysis: Quick Start Tutorial 8
In this tutorial you will forecast ozone design values at monitors in the Eastern United States. The steps in this analysis are as follows:

· Step 1. Start MATS . Start the MATS program and choose to do an Ozone analysis.

· Step 2. Output Choice . Choose the output to generate. In this example, you will forecast ozone levels at monitor locations.

· Step 3. Data Input . Choose the data files for input to MATS.

· Step 4. Filtering & Interpolation . Choose the particular years of data and monitors to use in this analysis.

· Step 5. RRF & Spatial Gradient . Specify how to generate the relative response factors (RRFs) used in the forecasts.

· Step 6. Final Check . Verify the choices you have made.

· Step 7. Load & Map Output . Load your output and prepare maps of your forecasts.

· Step 8. View & Export Output . Examine the data in a table format and export these data.

Each step is explained below. Additional details are provided in the section Ozone Analysis: Details

. 

## 8.1 Step 1. Start MATS Double-click on the MATS icon on your desktop, and the following window will appear:Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 217 

### Click the Ozone Analysisbutton on the main MATS window. This will bring up the Configuration Managementwindow.

A Configurationallows you to keep track of the choices that you make when using MATS. For example, after generating results in MATS, you can go back, change one of your choices, rerun your analysis, and then see the impact of this change without having to enter in all of your other choices. For this example, we will start with a New Configuration

. Choose Create New Configurationand click the Gobutton. This will bring up the Choose Desired Outputwindow. 

## 8.2 Step 3. Data Input
The Data Inputwindow allows you to choose the monitor data and the model data thatOzone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 218 

### you want to use. As discussed in more detail in the following chapter (see RRF Setup ), MATS calculates the ratio of the base and future year model data to calculate a relative response factor (RRF). MATS then multiplies the design valuefrom the monitor data with the RRF to calculate a future-year design value. MATS currently comes loaded with ozone design values for the period from 1998-2009 (1998-2000, 1999-2001, 2000-2002, 2001-2003, 2002-2004, 2003-2005, 2004-2006, 2005-2007, 2006-2008, 2007-2009); and it comes loaded with example ozone model data for 2001 and 2015. These are the files needed to calculate the Point Estimates and Spatial Fieldslisted in the Desired Outputwindow. Use the default settings in the Data Inputwindow. The window should look like the following:

Note that MATS gives you the option to use model data in different ways when calculating forecasts at each monitor. The user can choose to use the model results from the single grid cell that contains the monitor or select a grid cell array of 3x3, 5x5, or 7x7 model cells around each monitor. The example model output dataset contained in MATS is at 12km resolution. Therefore, for this example, a 3x3 grid cell array should be used (see section 3.2 of the modeling guidance). The default for ozone analysis is to choose the maximum value each day in the array for the calculation. This is described in more detail in the Using Model Datasection of the Ozone Analysis: Detailschapter

. When your window looks like the window above, click Next . This will bring you to the Filtering and Interpolationwindow.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 219 

## 8.3 Step 2. Output Choice
The Choose Desired Outputwindow allows you to choose the output that you would like to generate. MATS allows you to forecast Point Estimates(at ambient monitors) or to generate a Spatial Fieldof either Baseline values or Forecast values. In the Scenario Namebox type “ Tutorial O3 ”

–this will be used to keep track of where your results are stored and the variable names used in your results files. Leave the box checked next to Temporally-adjust ozone levels at monitors
. MATS will create forecasts for each monitor in the monitor file. Check the box next to Automatically extract all selected output files . MATS will create a separate folder called "Tutorial O3" in the MATS "Output" folder, and then export .CSV files with the results of your analysis. Alternatively, you can export the results from the Output Navigator , but checking this box is a little easier.

When your window looks like the window above, click Next . This will bring you to the Data Inputwindow.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 220 

## 8.4 Step 4. Filtering and Interpolation
TheFiltering and Interpolationwindow has several functions. These include identifying the years of monitor data that you want to use, choosing the particular monitors in these data that you want in your analysis, and (when calculating spatial fields ) specifying the interpolationmethod. Use the default settings pictured in the screenshot below.

· Choose Ozone Design Values

. Choose the years of design values that you want to use. The default is to use a 5 year period (3 design values) that is centered about the base emissions year. The default in MATS assumes an emissions year of 2007. Therefore, the design value would be based on data from 2005-2007 up through a design value based on data from 2007-2009. (That is, the Start Yearis 2005-2007 and the End Year is 2007-2009 .)

· Valid Ozone Monitors . Identify "valid" monitors -- that is, those monitors that you want to include in the analysis. The defaults are that monitors should have at least one valid design value period; and are within 25 kilometers of a model grid cell. You can also specify that a monitor must have a particular design value ( e.g. , 2005-2007) to be valid, however the default is to require none in particular.

· Default Interpolation Method . Choose the interpolation method -- that is, the method to combine the design values from different monitors into a single estimated design value. This option is only used when generating estimates for a Spatial Field. Since we are only generating Point Estimates , this set of options is not active.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 221 

### When your window looks like the window above, click Next . This will bring you to the RRF & Spatial Gradientwindow, where you can set parameters for the calculation of RRFs and spatial gradients

. 

## 8.5 Step 5. RRF & Spatial Gradient
The RRF and Spatial Gradient window has two sets of options.

· The RRF Setupdetermines the days to be used in the calculation of relative response factors (RRFs ). By default, MATS will select the top 10 highest days for the calculation. Each monitor must meet the minimum allowable threshold value and the minimum number of days at or above minimum allowable threshold value specified in this screen, or it is dropped from the calculation. The default values are 60 and 5, respectively.

· The Spatial Gradient Setupidentifies the model values that will be used in the calculation of a Spatial Field . Since we are only generating Point Estimates , this set of options is not active.

When your window looks like the window above, click Next . This will take you to the Final Check window, where you can verify the choices that you have made.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 222 * The default values in MATS are consistent with the recommended values in the EPA modeling guidance (see section 14.1.1). 

## 8.6 Step 6. Final Check
The Final Checkwindow verifies the choices that you have made. For example, it makes sure that the paths specified to each of the files used in your Configurationare valid. Click on the Press here to verify selectionsbutton.

If you encounter any errors, go back to the choices you have previously made by clicking on the appropriate part ( e.g. , Data Input) of the tree in the left panel, and then make any changes required. When your window looks like the window above, click either Save Scenario & Runor Save Scenario. Save Scenario & Run will cause MATS to immediately run the scenario. A temporary, new Runningtab will appear (in addition to the Start , Map Viewand Output Navigatortabs).Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 223 

### When the calculations are complete, a small window indicating the results are Donewill appear. Click OK

.

After clicking OK , the Output Navigatortab will be active. (The Runningtab will no longer be seen.) MATS will automatically load the output files associated with the .asr configuration that just finished running.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 224 

### The next step ( click here ) shows you how to map your results with the Output Navigator

. For more details on mapping and other aspects of the Output Navigator , there is a separate chapter on the Output Navigator

. 

## 8.7 Step 7. Load & Map Output After generating your results, Output Navigatorcan be used to load and/or map them. If a run just finished, the output files will already be loaded into output navigator. If files from a previous run need to be loaded then click on the Loadbutton and choose the Tutorial O3.asr file.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 225 

### Under Configuration/Log Files , you will see two files:

· Configuration : keeps track of the assumptions that you have made in your analysis.

· Log File : provides information on a variety of technical aspects regarding how a results file (*.ASR) was created. Under Output Filesyou will see:

· Tutorial O3 - Ozone Monitors - monitor data, temporally adjusted 2015 : contains forecasted values and the monitor data used.

· Tutorial O3 - Ozone Monitors - county high monitoring sites, temporally adjusted 2015 : contains forecasted values and the monitor data used for the monitor with the highest levels in the county. Right-click on the file Tutorial O3 - Ozone Monitors - monitor data temporally adjusted 2015 . This gives you three options: Add to Map , View , and Extract . Choose the Add to Mapoption.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 226 

### This will bring up the Map Viewtab.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 227 

### To view an enlarged map, use the Zoom to an areaTask Bar button on the far left. Choose the Continental US

.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 228 

### To more easily view the location of monitors in particular states, uncheck US Counties using the Standard Layersdrop down menu on the far right of the Task Bar. Your window should look like the following:

Zoom in further on the Eastern US using the Zoom inbutton on the Task Bar. This allows you to view the results more closely. A dashed line surrounds the area that you have chosen and should look something like the following:Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 229 

### Right click on the " Tutorial O3 - Ozone Monitors - "layer in the panel on the left side of the window. Choose the Plot Valueoption.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 230 

### This will bring up Shape Class Breakswindow. In the Valuedrop-down list, choose the variable " f_o3_dv " -- this is forecasted ozone design value for 2015.

Click Applyand then click Close . This will bring you back to the Map Viewwindow.

Examine the other variables: b_o3_dv : baseline ozone design value;Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 231 

### rrf : relative response factor used to forecast the ozone design value; ppb : value of the threshold used; day: number of days at or above the threshold. This is just a brief summary of the mapping possibilities available. For more details, there is a separate chapter on the Map View . The next stepis to go to the Output Navigatorto view the data in a table format. 

## 8.8 Step 8. View & Export Output After mapping your results, click on the Output Navigatortab, so that you can then view the data in a table. Right-click on the file Tutorial O3 - Ozone Monitors - monitor data temporally adjusted 2015 . This gives you three options: Add to Map , View , and Extract

. Choose the Viewoption.

This will bring up a Monitor Network Datatab. The upper left panel allows you to view the ID and latitude and longitude of the monitors in your data -- at the right of this panel there is a scrollbar with which you can locate any particular monitor of interest. The lower left panel allows you to view the other variables in the data.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 232 

### The default option is to show all of the data in the lower left panel. If, however, you want to just view the data for a particular monitor -- in this example, monitor ID = "010331002" -- use the scrollbar (if needed) and then highlight this monitor. MATS will then display the values for this monitor in the bottom panel.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 233 

### To view all of the data again, click on the Show Allbutton.

To eliminate missing values (denoted by negative numbers in the lower panel), check oneOzone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 234 

### or more boxes in the panel in the upper right of the window. For example, to eliminate any monitors that do not have a ozone design value forecast, check the forecasted ozone design value variable " f_o3_dv ". MATS will automatically drop these values. (Note that the monitor that we previously highlighted [monitor ID = "010331002] has now dropped out of the display.)

Click the Exportbutton and save the file as " O3 Tutorial No Negative Forecasts ." (It is unnecessary to add an extension. MATS automatically saves the file as a CSV text file and adds a ".csv" extension to your file name.) View the file in Excel.Ozone Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 235 

### For additional details on generating ozone results, see the chapter on Ozone Analysis: Details . For additional details on viewing data, see the View Data section in chapter on the Output NavigatorOzone Analysis: Details

April 2014 Abt Associates Inc. 236 

## 9 

# Ozone Analysis: Details 9
MATS can forecast design values at ozone monitor locations -- these forecasts are referred to as Point Estimates . MATS can also use a variety of approaches to calculate design values for a Spatial Field . A Spatial Field refers to a set of values comprising calculations for each grid cell in a modeling domain from Eulerian grid models such as CMAQ and CAMx. The set of choices involved in calculating either Point Estimatesor a Spatial Field can be fairly involved, so MATS keeps track of these choices using a Configuration . When you begin the process of generating ozone estimates, MATS provides an option to start a new Configuration or to open an existing Configuration.

Select your option and then click Go

. MATS will then step you through a series of windows with choices for your analysis.

· Choose Desired Output
. Choose whether you want Point Estimates, estimates for a Spatial Field, or both.

· Data Input
. Specify the air quality modeling and ambient monitoring data that you want to use. Specify which model grid cells will be used when calculating RRFs at monitor locations.

· Filtering Interpolation . Choose the years of monitoring data. Identify valid monitors. Define the interpolation approach to be used (when calculating a Spatial Field).

· RRF and Spatial Gradient
. Specify the daily ozone values that will be used in the calculation of RRFs and Spatial Gradients

.
· Final Check . Verifythe selections that you have made. 

## 9.1 Choose Desired Output MATS lets you choose to generate Point Estimates, which refer to forecasts made at fixed locations, such as monitors. MATS can also generate Spatial Fields, which refer to air pollution estimates made at the center of each grid cell in a specified model domain. (For example if the model domain has 20 columns and 30 rows, then there are 600 grid cells for which MATS can generate estimates.) The Spatial Field estimates can be baseline estimates or forecasts, generated with or without a gradient adjustment

.Ozone Analysis: Details

April 2014 Abt Associates Inc. 237 

### By checking the box next to Automatically extract all selected output files, MATS will create a separate folder with your chosen Scenario Name in the MATS "Output" folder, and then export .CSV files with the results of your analysis. Alternatively, you can export the results from the Output Navigator , but checking this box is a little easier.



## 9.1.1 Scenario Name The Scenario Name allows you to uniquely identify each analysis that you conduct. It is used in several ways.

· Results file name . The results file is given the Scenario Name(e.g., Example O3.asr). Note that the extension ( .ASR ) is specifically designated just for MATS and can only be used by MATS.

· Organize output . In the Output folder, MATS will generate a folder using the Scenario Name . MATS will use this folder as a default location for files generated with this Scenario Name.Ozone Analysis: Details

April 2014 Abt Associates Inc. 238 

### · Output file names . The output files generated will begin with the Scenario Name.Ozone Analysis: Details

April 2014 Abt Associates Inc. 239 

## 9.1.2 Point Estimates The calculation of Point Estimates , or future-year ozone levels at monitors, has several steps (the process is laid out in more detail in Sections 3 and 4 of the EPA modeling guidance). The first step is to calculate the baseline value as a function of up to three design values. The second step is to use model data to temporal adjust the baseline value.

9.1.2.1 Baseline Ozone The baseline ozone design valueis the simple average of design values, where the average carries one significant figure to the right of the decimal point. Generally, one should select design value years that match the modeling data being used. The EPA modeling guidance recommends using an average of the 3 design values periods which straddle the emissions base year. For example, if the modeled emissions base year is 2007, then design values from 2005-2007, 2006-2008, and 2007-2009 would be averaged. An average of design values is, in effect, a weighted average of annual averages -- 2007 is “weighted” three times, 2006 and 2008 are weighted twice, and 2005 and 2009 are weighted once. This creates a 5-year weighted average design value which is used to project future air quality levels. The default design value years in MATS are the periods 2005-2009. This assumes a model base year of 2007. If the base year is not 2007, then the start and end design value period should be adjusted.
9.1.2.2 Temporally-Adjust Baseline Ozone The first step in temporally adjustingbaseline ozone involves identifying the model grid cells near the monitor site. Next, MATS calculates the average of daily 8-hour average maximum model values for both the baseline and future-year model runs, and then takes the ratio of the two to calculate the RRF . Finally, MATS calculates the future-year design value by multiplying the RRF with the baseline design value measured at the monitor. The equation for temporally adjusting baseline ozone is as follows:

where: Monitori, future

### = future-year ozone design value at monitor site i, measured in parts per billion (ppb)Ozone Analysis: Details

April 2014 Abt Associates Inc. 240 

### Monitori

### = baseline ozone design value at monitor site i, measured in ppb
RRFi

### = relative response factor at monitor site i. The RRF is the ratio of the future 8-hour daily maximum concentration predicted near a monitor (averaged over multiple days) to the baseline 8-hour daily maximum concentration predicted near the monitor (averaged over the same days). NOTE: The calculation of the RRF involves a number of assumptions that are specified in the RRF and Spatial Gradient window.


## 9.1.3 Spatial Field A Spatial Fieldrefers to air pollution estimates made at the center of each grid cell in a specified model domain . For example, MATS might calculate ozone design values for each grid cell in a modeling domain. MATS calculates four types of ozone-related Spatial Fields:

· Baseline - interpolate monitor data to spatial field . This is an interpolation of baseline monitor values at each grid cell. MATS identifies the "neighbor" monitors for each grid cell and then calculates an inverse-distance-weighted average of the monitor values at each grid cell.

· Baseline - interpolate gradient-adjusted monitor data to spatial field . This is an interpolation of model-adjustedbaseline monitor values at each grid cell. MATS identifies the "neighbor" monitors for each grid cell, it adjusts the monitor values toaccount for the modeled spatial gradient, and then calculates an inverse-distanceweighted average of the monitor values.

· Forecast - interpolate monitor data to spatial field. Temporally Adjust

. This is an interpolation of baseline monitor values at each grid cell that are then temporally adjusted to a future year. MATS calculates the Baseline - interpolate monitor data to spatial fieldand multiplies it with a RRF

.

· Forecast - interpolate gradient-adjusted monitor data to spatial field. Temporally adjust

. This is an interpolation of model-adjusted baseline monitor values at each grid cell that are then temporally adjusted to a future year. MATS calculates the Baseline - interpolate gradient-adjusted monitor data to spatial fieldand multiplies it with a RRF. Details on the calculations are provided in the following sections.Ozone Analysis: Details

April 2014 Abt Associates Inc. 241 

### 9.1.3.1 Baseline - interpolate monitor data to spatial field Using modeling data for gradient scalingis fairly simple: MATS uses the model value for the grid cell of interest and the model values for the grid cells containing the monitors to be interpolated to the grid cell of interest. A general form of the equation is as follows:

where: Gridcell E, baseline

### = baseline ozone concentration at unmonitored site E; Weighti

### = inverse distance weight for monitor i;
Monitori

### = baseline ozone concentration at monitor i; Gradient Adjustmenti, E

### = gradient adjustment from monitor i to unmonitored site E.

There are a variety of approaches that might be used to calculate the gradient adjustment. As a default, MATS averages the five highest daily 8-hour values. The equation can then be rewritten as follows:

where: Model E, baseline

### = baseline scenario, average of five highest daily 8-hour values at site E;
Model i, baseline

### = baseline scenario, average of five highest daily 8-hour values at monitorOzone Analysis: Details

April 2014 Abt Associates Inc. 242 

### site i.
9.1.3.2 Baseline - interpolate gradient-adjusted monitor data to spatial field Using modeling data for gradient scalingis fairly simple: MATS uses the model value for the grid cell of interest and the model values for the grid cells containing the monitors to be interpolated to the grid cell of interest. A general form of the equation is as follows:

where: Gridcell E, baseline

### = baseline ozone concentration at unmonitored site E; Weighti

### = inverse distance weight for monitor i;
Monitori

### = baseline ozone concentration at monitor i; Gradient Adjustmenti, E

### = gradient adjustment from monitor i to unmonitored site E.

There are a variety of approaches that might be used to calculate the gradient adjustment. As a default, MATS averages the five highest daily 8-hour values. The equation can then be rewritten as follows:

where: Model E, baseline

### = baseline scenario, average of five highest daily 8-hour values at site E;
Model i, baseline

### = baseline scenario, average of five highest daily 8-hour values at monitor site i.
9.1.3.3 Forecast - interpolate monitor data to spatial field. Temporally-adjust ozone levels To get the forecasted design valuefor each grid-cell in the spatial field , MATS multiplies the Baseline - interpolate monitor data to spatial fieldfor each grid-cell with the RRF calculated for that grid-cell. The equation is as follows:Ozone Analysis: Details

April 2014 Abt Associates Inc. 243 

### where: Gridcell E, baseline

### = baseline ozone concentration at unmonitored site E; Weighti

### = inverse distance weight for monitor i;
Monitori

### = baseline ozone concentration at monitor i.

NOTE: The RRF is calculated using the same approach as for Point Estimates(except when a backstop threshold minimum is set [ see section 9.4.1.6 ]).
9.1.3.4 Forecast - interpolate gradient-adjusted monitor data to spatial field. Temporally-adjust ozone levels To get the forecasted design valuefor each grid-cell in the spatial field witha gradient adjustment , MATS multiplies the Baseline - interpolate gradient-adjusted monitor data to spatial fieldfor each grid-cell with the RRFcalculated for that grid cell. The equation is as follows:

where: Gridcell E, baseline

### = baseline ozone concentration at unmonitored site E; Weighti

### = inverse distance weight for monitor i;
Monitori

### = baseline ozone concentration at monitor i. NOTE: The RRF is calculated using the same approach as for Point Estimates (except when a backstop threshold minimum is set [ see section 9.4.1.6 ]).


## 9.1.4 Design Value Periods Normally, MATS will output one set of files covering the entire analysis period specified by the user. The outputs represent the averages of the values for each 3-year design value period. If the "Output design value periods" option is checked, MATS will produce discrete outputs for each design value period. The output files will be the same as a standard analysis, but with "Period 1", "Period 2", etc., attached at the end of the name. Please note, however, that checking this option will substantially increase the MATS run time, by up to four times.Ozone Analysis: Details

April 2014 Abt Associates Inc. 244 

### The maximum design values are based on the highest future year value from the three design value periods. These values can be output by checking the "Output design value periods maxima" option. The output file will be the same as a standard analysis, but with “maximum forecast” inserted into the file name.


## 9.1.5 Ozone Output Variable Description MATS generates up to three output files:

· Ozone forecasts for all monitors . The name of this file is "Ozone Monitors -- monitor data, temporally adjusted yyyy .csv" with the Scenario Nameappended at the beginning and the forecast year is inserted at the end (e.g., "Example O3 -- Ozone Monitors -- county high monitoring sites, temporally adjusted 2015.csv").

· Ozone forecasts for the highest monitor in each county . The name of this file is "Ozone Monitors -- county high monitoring sites, temporally adjusted yyyy .csv" with the Scenario Name appended at the beginning and the forecast year inserted at the end.

· Spatial field forecasts . The name of this file is "Spatial Field -- interpolated monitor data, temporally adjusted; gradient-adjusted monitor data, temporally adjusted yyyy .csv" with the Scenario Name appended at the beginning and the forecast year inserted at the end. The following sub-sections describe the variables in each file.
9.1.5.1 Ozone Monitors -- monitor data, temporally adjusted 2015.csv The table below describes the variables in the output file.
Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _type Leave blank lat Latitude in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. long Longitude in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. date The date represents the last year of the chosen design value periods (e.g., if a 5 year period is chosen, 2009 represents the 2005-2009 period ). b_o3_DV Baseline design value f_o3_DV Forecasted (future year) design value referencecell Identifier of the closest model grid cell centroid to the monitor. rrf Relative response factor is the ratio of the future year modeled concentration predicted near a monitor (averaged over multiple days) to the base year modeled concentration predicted near the monitor (averaged over the same days). ppb Threshold value (measured in parts per billion) used in the rrf calculationOzone Analysis: Details

April 2014 Abt Associates Inc. 245 days Number of days at or above the threshold value. _state_name State name. (This is a character variable.) _county_name County name. (This is a character variable.)



### 9.1.5.2 Ozone Monitors -- county high monitoring sites, temporally adjusted 2015.csv An example of this output file is as follows (with variable definitions in the table below):
Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _type Leave blank lat Latitude in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. long Longitude in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. date The date represents the last year of the selected design value periods (e.g., if a 5 year period is selected, 2009 represents the 2005-2009 period ). b_o3_DV Baseline design value f_o3_DV Forecasted (future year) design value referencecel l Identifier of the closest model grid cell centroid to the monitor.
rrf Relative response factor is the ratio of the future year modeled concentration predicted near a monitor (averaged over multiple days) to the base year modeled concentration predicted near the monitor (averaged over the same days). ppb Threshold value (measured in parts per billion) used in the rrf calculation days Number of days at or above the threshold value. _state_nam e State name. (This is a character variable.) _county_na me County name. (This is a character variable.)



### 9.1.5.3 Spatial Field -- interpolated monitor data, temporally adjusted; gradient-adjusted monitor data, temporally adjusted 2015.csv An example of this output file is as follows (with variable definitions in the table below):
Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) _type Leave blank lat Latitude in decimal degrees of the center of each grid cell. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative.Ozone Analysis: Details

April 2014 Abt Associates Inc. 246 long Longitude in decimal degrees of the center of each grid cell. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative.
date The date represents the last year of the selected design value periods (e.g., if a 5 year period is selected, 2009 represents the 2005-2009 period ). ga_conc Modeled concentration (ppb) used for gradient adjustment (average of "start value" and "end value") i_b_o3 Interpolated (to spatial field) baseline concentration (ppb). i_f_o3 Interpolated (to spatial field) future year concentration (ppb). i_b_ga_o3 Interpolated (to spatial field) gradient adjusted baseline concentration (ppb). i_f_ga_o3 Interpolated (to spatial field) gradient adjusted future year concentration (ppb). ppb Threshold value (measured in parts per billion) used in the rrf calculation days Number of days at or above the threshold value. referencecell Identifier of the grid cell. (In the case of spatial fields, this is identical to the _ID variable.) rrf Relative response factor is the ratio of the future year modeled concentration predicted near a monitor (averaged over multiple days) to the base year modeled concentration predicted near the monitor (averaged over the same days).



## 9.2 Data Input In the Data Input window, you need to specify the air quality modeling and ambient monitoring data that you want to use. In addition, you need to specify which model grid cells will be used when calculating RRFs at monitor locations.Ozone Analysis: Details

April 2014 Abt Associates Inc. 247 

## 9.2.1 Monitor Data Monitor data should be in the form of a simple text file. The first row specifies the frequency of the data ( e.g ., day). The second row presents comma-separated variable names. The third row begins the data values. Below is an example of the monitor data file format and descriptions of the variables in the file. Format of Ozone Monitor Data

Ozone Monitor Data Variable Descriptions
Variable DescriptionOzone Analysis: Details

April 2014 Abt Associates Inc. 248 _ID The ID is a unique name for each monitor in a particular location. The default value is the AIRS ID. (This is a character variable.) _TYPE Leave this blank. LAT Latitude in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. LONG Longitude in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. DATE The time period of the monitor observation. As a convention, the date represents the last year of the three-year design value period (e.g., 2001 represents the 1999-2001 design value).
O3 Observed monitor value. Note that missing values are represented by a minus nine (-9). _STATE_NAME State name. (This is a character variable.) _COUNTY_NAME County name. (This is a character variable.)


### Note:

· Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.)


## 9.2.2 Model Data The model data should be in the form of a simple text file. The first row specifies the frequency of the data ( e.g ., day). The second row presents comma-separated variable names. The third row begins the data values. The ozone model data should be the daily 8- hour average maximum concentration in each grid cell. Below is an example of the model data file format and descriptions of the variables in the file. Format of Ozone Model Data

Ozone Model Data Variable Descriptions
Variable DescriptionOzone Analysis: Details

April 2014 Abt Associates Inc. 249 _ID The ID is a unique number for each model grid cell in the air quality model domain. It is generally based on the column and row identifiers from the air quality modeling domain. The default convention is to calculate the ID by multiplying the column identifier by one thousand (1000) and adding the row identifier. (This is a character variable.) _TYPE Leave this blank. LAT Latitude in decimal degrees of the center of each grid cell. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. LONG Longitude in decimal degrees of the center of each grid cell. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative.
DATE The time of the monitor observation. The day is represented in the yyyymmdd format O3 Modeled ozone concentration (8-hour average daily maximum).


### Note :

· Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.)
9.2.2.1 EPA Default Model Data The example model output dataset in MATS comprises daily 8-hour average maximums from May-September at 12km resolution. The baseline year for the modeling is 2001 and the future year is 2015.


## 9.2.3 Using Model Data The RRF for a monitor is calculated from "nearby" model grid cells. For purposes of this calculation, a monitor is assumed to be at the center of the cell in which it is located, and this cell is at the center of an array of “nearby” cells. The number of cells considered “nearby” a monitor is a function of the size of the grid cells used in the modeling. In the example case of a 12 km grid, EPA uses as a default 3x3 array of grid cells (see section 3.2 of the EPA modeling guidance for more details).Ozone Analysis: Details

April 2014 Abt Associates Inc. 250 

### With the array size determined, MATS gives you two options for how you might use the modeling data.

· Maximum . For each day of modeling data, MATS will identify the highest 8-hour daily maximum among the grid cells in the chosen array. In the case of a 3x3 array, MATS will identify the highest daily 8-hour average maximum from among the nine “nearby” grid cells for each day and for each monitor site.

· Mean . For each day of modeling data, MATS will average the 8-hour daily values for the grid cells in the chosen array. In the case of a 3x3 array, MATS will average nine values.

· Maximum-paired in space . For each day of modeling data, MATS will identify the grid cell with the highest 8-hour daily maximum in the chosen array in the baseline file, and calculate the RRF using the same grid cell in the control file.Ozone Analysis: Details

April 2014 Abt Associates Inc. 251 

### The default choice for the ozone analysis in MATS is to use themaximum-paired in spaceoption when calculating temporally-adjusted ozone levels at each monitor. NOTE: For monitors on the border of a modeling domain -- where it may not be possible to have a full set of neighbors -- MATS uses the available modeling data.
9.2.3.1 Nearby Monitor Calculation - Example 1 Given : (1) Four primary days have been simulated using baseline and future emissions. (2) The horizontal dimensions for each surface grid cell are 12 km x 12 km. (3) In each of the 9 grid cells “near” a monitor site I, the maximum daily predicted future concentrations are 87.2, 82.4, 77.5, and 81.1 ppb. (4) In each of the 9 grid cells “near” a monitor site I, the maximum daily predicted baseline 8-hour daily maximum ozone concentrations are 98.3, 100.2, 91.6, and 90.7 ppb. Find : The site-specific relative response factor for monitoring site I, (RRF)IOzone Analysis: Details

April 2014 Abt Associates Inc. 252 

### Solution : (1) For each day and for both baseline and future emissions, identify the 8-hour daily maximum concentration predicted near the monitor. Since the grid cells are 12 km, a 3 x 3 array of cells is considered “nearby.” (2) Compute the mean 8-hour daily maximum concentration for (a) future and (b) baseline emissions. Using the information from above, (a) (Mean 8-hr daily max.)future = (87.2 + 82.4 + 77.5 + 81.1)/4 = 82.1 ppb and (b) (Mean 8-hr daily max.)baseline = (98.3 + 100.2 + 91.6 + 90.7)/4 = 95.2 ppb (3) The relative response factor for site I is (RRF)I = (mean 8-hr daily max.)future/(mean 8-hr daily max.)baseline = 82.1/95.2 = 0.862.Ozone Analysis: Details

April 2014 Abt Associates Inc. 253 

## 9.3 Filtering and Interpolation
The Filtering and Interpolationwindow allows you to choose the years of monitoring data that you will use in your analysis. MATS allows you to specify the rules to determine the monitors that you will use. And in the case of calculating Spatial Fields, it allows you to define the interpolation method that MATS will use.



## 9.3.1 Choose Ozone Design Values Choosing the Start Yearand the End Yeardefines the range of the ozone design values that will be used in the calculation of the baseline ozone level. You can vary the number of design values used in this calculation. The database that comes with MATS has design values periods from (1998-2000)-(2007- 2009). The default approach in MATS is to average 3 design value periods. For example, if the modeling base year is 2007, then you would use the design values from 2005-2007, 2006-2008, and 2007-2009. The Start Yearis set to 2005-2007 and the End Yearis set to 2007-2009.Ozone Analysis: Details

April 2014 Abt Associates Inc. 254 

## 9.3.2 Valid Ozone Monitors MATS provides two choices for identifying monitors that are "valid" and thus included in your analysis.

· Minimum Number of Design Values . Specifies the minimum number of design value periods that need to be included in the calculation of the baseline ozone design value (1, 2, or 3).

· Required Design Values . Specifies whether a particular design value period needs to be valid for the calculations to be performed at that monitor.

9.3.2.1 Minimum Number Design Values The Minimum Number of Design Valuess pecifies the minimum number of design values that need to be available in the potential range of design values specified by the Start Year and End Year. Monitors that do not meet the minimum are excluded from the calculation of baseline ozone levels. Recall that the baseline ozone level is an average of one or more design values. The number of design values available for this calculation will typically be either 1, 2, or 3 design value periods. The default option is to require that one design value be available in the specified range.

Example 1: Point EstimatesOzone Analysis: Details

April 2014 Abt Associates Inc. 255 

### When calculating ozone levels at monitors, if MATS finds that a monitor has an insufficient number of valid design values (e.g., one required but none available in the specified range), then MATS will set the baseline level and forecast values to missing ( denoted by a negative number). Example 2: Spatial Field The calculation of the ozone level in each grid cell of a Spatial Field involves multiple monitors. MATS uses Voronoi Neighbor Averaging to identify "neighboring" monitors from the available set of valid monitors, and then calculates an inverse-distance weighted average of the baseline ozone levels from these neighbors. The Minimum Number of Design Valuesdetermines which monitors are "valid" -- that is, those monitors that will be included in the calculation.
9.3.2.2 Required Design Values Using the Required Design Valuedrop-down list, you can specify that a particular design value must be available at each monitor included in the analysis. If you want to use all monitors that have a valid design value for 2001-2003, then MATS will only include those monitors that have this valid design value. The default is to choose None Selected

.



## 9.3.3 Default Interpolation Method The Default Interpolation Methodpanel allows you to choose how you will interpolate , or combine, the values from different monitors. One approach is to use Inverse Distance Weights . This means that the weight given to any particular monitor is inversely proportional to its distance from the point of interest. A second approach is Inverse Distance Squared Weights, which means that the weights are inversely proportional to the square of the distance. And the third approach is Equal Weighting of Monitors. The default approach for ozone is Inverse Distance Weights.

When interpolating monitor values, MATS allows you to identify the monitors you want to use based on their distance away from the point of interest ( e.g. , the center of a grid cell). The first step in the interpolation process is to identify the monitors that are nearby, orOzone Analysis: Details

April 2014 Abt Associates Inc. 256 

### neighbors, for each point of interest. The next step is to determine the distance from the nearby monitors to the point of interest. The default approach is to include all valid monitors ( i.e. , those that satisfy the two criteria in the Valid Ozone Monitors panel), regardless of distance. If you want to limit the use of monitors based on distance, check the box next to check to set a maximum interpolation distance , and then specify a distance (in kilometers). A distance of one hundred (100) kilometers means that any monitors further than 100 kilometers can no longer be used in the interpolation. If a point of interest has no monitors within the specified distance, then no value is calculated. The default is to leave this box unchecked.



## 9.4 RRF and Spatial Gradient In calculating an ozone RRFor a Spatial Gradient , typically, not all of the model data are used. In the case of RRFs, daily values falling below specified thresholds can be excluded from the calculation ( e.g. , RRF Calculation - Example 1 ) . In the case of a spatial gradient, MATS be be setup to follow the same thresholds as used for point estimates or if a valid result is needed in all grid cells, a Backstop minimum thresholdcan be used ( e.g. , RRF Calculation Spatial Gradient with Backstop Threshold - Example 6 ). You can also specify a sub-range of days included in the model data files and base and future year model dayscan be paired by high concentration instead of by date. MATS also averages a userspecified range of values to calculate gradient adjustments ( e.g. , Spatial Gradient Calculation - Example 1 )

.Ozone Analysis: Details

April 2014 Abt Associates Inc. 257 

## 9.4.1 RRF Setup The RRFSetup involves four variables that specify the thresholds and the numbers of days above the thresholds -- Initial threshold value; Minimum number of days in baseline at or above threshold; Minimum allowable threshold value ; and Min number of days at or above minimum allowable threshold

. The first step in calculating the RRF is to determines the number of days at or above the Initial threshold valueor select directly the top number of days based on value (Top X option in GUI). If the number of days is above the Minimum number of days in baseline at or above threshold , then MATS averages the 8-hour values for those grid cells with at least this number. For example, MATS performs the following steps:

· In the case of a 3x3 array, MATS identifies the highest daily 8-hour average maximum from among the nine “nearby” grid cells for each day and for each monitor site. In the case where there are 90 days of model outputs, MATS generates 90 daily values. NOTE: MATS can do this calculation separately for the baseline and future-year scenarios. As a result

–if you chose an option other than “Maximum

–paired in space” - two different grid cells in the baseline and future-year might be used to represent a given day.Ozone Analysis: Details

April 2014 Abt Associates Inc. 258 

### · MATS updated approach is as follows: MATS allows the user to specify the Top X days to be used in computing the RRF. MATS will then select the specified number of days based on their ranking by value and date. If there are fewer than the Min number of days at or above minimum allowable threshold, then the monitor site will be dropped. Otherwise the selected days will be used in computing the RRF. This new approach replaces the legacy approach that used the following algorithm: The default Initial threshold valueis set to 85 ppb. The default Minimum number of days in baseline at or above thresholdis set to 10. If there are fewer than 10 days at or above 85 ppb in the baseline scenario, then MATS lowers the threshold in increments of 1 ppb, until there are at least 10 days at or above this new, lower threshold. This process is continued, if needed, until the Minimum allowable threshold valueis reached. The default Minimum allowable threshold valueis 70 ppb. MATS calculates the number of days at or above the Minimum allowable threshold value

. If there are fewer than the Min number of days at or above minimum allowable threshold , then the monitor site will be dropped. The default Min number of days at or above minimum allowable thresholdis 5.

· Using the threshold established with the baseline scenario, MATS checks the daily 8- hour maxima calculated for the baseline scenario, and sets to missing any daily value falling below the threshold. For any day set to missing in the baseline scenario, MATS also sets the corresponding day in the future-year scenario to missing.

· For each monitor site, MATS averages the non-missing daily values for the baseline and future-year scenarios, and then calculates the RRF as the ratio of the future-year average to the baseline average. You can also set a Backstop minimum threshold for spatial fields . As noted in Example 6 (below ), the backstop minimum threshold allows the minimum threshold to be lowered to a value below the Minimum allowable threshold valueuntil the minimum number of days is reached. The backstop threshold is only used for grid cells which do not have enough days to meet the minimum number of days value with the minimum allowable threshold. The backstop threshold does not change the calculation for grid cells that already meet the minimum number of days. Another option is to specify a Subrangeof days to use in the model RRF calculation. The start day and end day of the subrange are specified based on a count of the number of daysfrom the first day in the file. For example, if the model files contained data for June 1stAugust 30th, a subrange start and end day of "31" and "61" respectively would specify the July 1st-July 31st period. There is also an option to pair days based on high concentration instead of date . This may be useful for model runs where the future year meteorology is different than the base year (such as climate modeling). MATS will pair the future year highest concentrations with the highest concentrations in the base year file, regardless of date. The number of days in the RRF will continue to be based on the threshold variables. For example, if 11 days are greater than the selected threshold in the base year, then the RRF will be calculated based on the 11 highest base and future year concentration days.Ozone Analysis: Details

April 2014 Abt Associates Inc. 259 

### 9.4.1.1 RRF Calculation - Example 1 Assume the following default values:

Assume that there are 15 days of data: Baseline day Baseline value Future day Future value

1 103 1 95 2 112 2 97 3 98 3 94 4 97 4 95 5 95 5 94 6 95 6 93 7 94 7 89 8 92 8 86 9 90 9 80 10 85 10 78 11 89 11 80 12 88 12 81 13 85 13 76 14 78 14 75 15 78 15 74Ozone Analysis: Details

April 2014 Abt Associates Inc. 260 

### MATS will sort the values from high to low based on the Baseline values: Baseline day Baseline value Future day Future value

2 112 2 97 1 103 1 95 3 98 3 94 4 97 4 95 5 95 5 94 6 95 6 93 7 94 7 89 8 92 8 86 9 90 9 80 11 89 11 80 12 88 12 81 10 85 10 78 13 85 13 76 14 78 14 75 15 78 15 74



### Note that Day 2 has the highest Baseline value. And note that the Future values are not sorted high to low, and instead the Future days match the Baseline days. MATS will take the top 10 days (highlighted in yellow) and then calculate separate averages for the Control and Baseline values: Control average = 90.3 ppb Baseline average = 96.5 ppb. The RRF equals the ratio of the Control to the Baseline: RRF = 90.3 / 96.5 = 0.936 Note that we report the RRF with three digits after the decimal point. The calculation of the Baseline and Control averages does not involve any rounding or truncation.
9.4.1.2 RRF Calculation - Example 2 In this example, MATS uses a threshold value instead of the top X number of days. Assume the following values:Ozone Analysis: Details

April 2014 Abt Associates Inc. 261 

### Assume that there are 15 days of data: Baseline day Baseline value Future day Future value

1 100 1 95 2 100 2 97 3 98 3 94 4 97 4 95 5 95 5 94 6 95 6 93 7 90 7 89 8 85 8 86 9 84 9 80 10 83 10 78 11 83 11 80 12 83 12 81 13 79 13 76 14 78 14 75 15 78 15 74Ozone Analysis: Details

April 2014 Abt Associates Inc. 262 

### MATS will sort the data from high to low based on the Baseline values: Baseline day Baseline value Future day Future value

1 100 1 95 2 100 2 97 3 98 3 94 4 97 4 95 5 95 5 94 6 95 6 93 7 90 7 89 8 85 8 86 9 84 9 80 10 83 10 78 11 83 11 80 12 83 12 81 13 79 13 76 14 78 14 75 15 78 15 74



### Note that the Baseline values happen to stay in the same order. And note that the Future values are not sorted high to low, and instead the Future days match the Baseline days. When you compare these sorted data with the Initial threshold valueof 85 ppb, note that there are only eight (8) Baseline values (highlighted in yellow) at or above this threshold. Since there are fewer days than the ten (10) specified as the Minimum number of days in baseline at or above threshold , MATS will then lower the threshold by one ppb to 84 ppb. There are nine (9) Baseline values at or above this lower threshold -- still less than the value of ten (10) that specified as the Minimum number of days in baseline at or above threshold . MATS will lower the threshold again by one ppb to 83 ppb. At this point, there are twelve (12) days at or above this threshold. MATS will take the top 12 days: Baseline day Baseline value Future day Future value

1 100 1 95 2 100 2 97 3 98 3 94 4 97 4 95 5 95 5 94 6 95 6 93 7 90 7 89 8 85 8 86Ozone Analysis: Details

April 2014 Abt Associates Inc. 263 9 84 9 80 10 83 10 78 11 83 11 80 12 83 12 81 13 79 13 76 14 78 14 75 15 78 15 74



### and then calculate separate averages for the Control and Baseline values: Control average = 88.5000 ppb Baseline average = 91.0833 ppb. The RRF equals the ratio of the Control to the Baseline: RRF = 88.5000 / 91.0833 = 0.972 Note that we report the RRF with three digits after the decimal point. The calculation of the Baseline and Control averages does not involve any rounding or truncation.
9.4.1.3 RRF Calculation - Example 3 In this example, MATS uses a threshold value instead of the top X number of days. Assume the following values:Ozone Analysis: Details

April 2014 Abt Associates Inc. 264 

### Assume that there are 15 days of data: Baseline day Baseline value Future day Future value

1 84 1 83 2 85 2 84 3 85 3 84 4 82 4 82 5 78 5 78 6 76 6 75 7 70 7 72 8 70 8 62 9 70 9 70 10 67 10 62 11 64 11 63 12 63 12 60 13 62 13 62 14 62 14 59 15 59 15 57Ozone Analysis: Details

April 2014 Abt Associates Inc. 265 

### MATS will sort the data from high to low based on the Baseline values: Baseline day Baseline value Future day Future value

2 85 2 84 3 85 3 84 1 84 1 83 4 82 4 82 5 78 5 78 6 76 6 75 7 70 7 72 8 70 8 62 9 70 9 70 10 67 10 62 11 64 11 63 12 63 12 60 13 62 13 62 14 62 14 59 15 59 15 57



### When you compare these sorted data with the Initial threshold valueof 85 ppb, note that there are only two (2) Baseline values at or above this threshold. Since there are fewer days than the ten (10) specified as the Minimum number of days in baseline at or above threshold , MATS will then lower the threshold by one ppb to 84 ppb. There are three (3) Baseline values at or above this lower threshold -- still less than the value of ten (10) that specified as the Minimum number of days in baseline at or above threshold . MATS will lower the threshold again by one ppb, and eventually get to the Minimum allowable threshold valueof 70 ppb. At this point, there are still only nine (9) days at or above this threshold. MATS will take the nine days (highlighted in yellow) above the Minimum allowable threshold value and then calculate separate averages for the Control and Baseline values: Control average = 76.6667 ppb Baseline average = 77.7778 ppb. The RRF equals the ratio of the Control to the Baseline: RRF = 76.6667 / 77.7778 = 0.986 Note that we report the RRF with three digits after the decimal point. The calculation of the Baseline and Control averages does not involve any rounding or truncation.Ozone Analysis: Details

April 2014 Abt Associates Inc. 266 

### 9.4.1.4 RRF Calculation - Example 4 In this example, MATS uses a threshold value instead of the top X number of days. Assume the following values:

Assume that there are 15 days of data: Baseline day Baseline value Future day Future value

1 67 1 65 2 74 2 73 3 70 3 69 4 68 4 66 5 78 5 77 6 66 6 64 7 66 7 63 8 65 8 63 9 63 9 63 10 62 10 60 11 61 11 61 12 60 12 59Ozone Analysis: Details

April 2014 Abt Associates Inc. 267 13 60 13 57 14 59 14 56 15 57 15 55



### MATS will sort the data sorted from high to low based on the Baseline values: Baseline day Baseline value Future day Future value

5 78 5 77 2 74 2 73 3 70 3 69 4 68 4 66 1 67 1 65 6 66 6 64 7 66 7 63 8 65 8 63 9 63 9 63 10 62 10 60 11 61 11 61 12 60 12 59 13 60 13 57 14 59 14 56 15 57 15 55



### When you compare these sorted data with the Initial threshold valueof 85 ppb, note that there are zero (0) Baseline values at or above this threshold. Since there are fewer days than the ten (10) specified as the Minimum number of days in baseline at or above threshold , MATS will lower the threshold by one ppb, and eventually get to the Minimum allowable threshold valueof 70 ppb. At this point, there are still only three (3) days at or above this threshold -- still less than the Min number of days at or above minimum allowable . As a result, MATS will not calculate a RRF and will set the future year design value to missing.
9.4.1.5 RRF Calculation - Example 5 In this example, MATS uses a threshold value instead of the top X number of days. Assume the following values:Ozone Analysis: Details

April 2014 Abt Associates Inc. 268 

### Assume that there are 15 days of data: Baseline day Baseline value Future day Future value

1 67 1 65 2 74 2 73 3 70 3 69 4 68 4 66 5 78 5 77 6 67 6 64 7 66 7 63 8 65 8 63 9 63 9 63 10 62 10 60 11 61 11 61 12 60 12 59 13 60 13 57 14 59 14 56 15 57 15 55Ozone Analysis: Details

April 2014 Abt Associates Inc. 269 

### MATS will sort the data from high to low based on the Baseline values: Baseline day Baseline value Future day Future value

5 78 5 77 2 74 2 73 3 70 3 69 4 68 4 66 1 67 1 65 6 67 6 64 7 66 7 63 8 65 8 63 9 63 9 63 10 62 10 60 11 61 11 61 12 60 12 59 13 60 13 57 14 59 14 56 15 57 15 55



### When you compare these sorted data with the Initial threshold valueof 85 ppb, note that there are zero (0) Baseline values at or above this threshold. Since there are fewer days than the ten (10) specified as the Minimum number of days in baseline at or above threshold , MATS will lower the threshold by one ppb, and eventually get to the Minimum allowable threshold valueof 62 ppb. At this point, there are ten (10) days at or above this threshold. MATS will take the ten days (highlighted in yellow) above the Minimum allowable threshold value and then calculate separate averages for the Control and Baseline values: Control average = 66.3000 ppb Baseline average = 68.0000 ppb. The RRF equals the ratio of the Control to the Baseline: RRF = 66.3000 / 68.0000 = 0.975 Note that we report the RRF with three digits after the decimal point. The calculation of the Baseline and Control averages does not involve any rounding or truncation.
9.4.1.6 RRF Calculation Spatial Gradient with Backstop Threshold - Example 6 The following is an example showing the difference between RRF s calculated for Point Estimates and RRFs calculated for Spatial Fields. The key difference is that MATS allows you to choose a Backstop minimum threshold for spatial fields , which applies just toOzone Analysis: Details

April 2014 Abt Associates Inc. 270 

### Spatial Fields. This extra parameter allows you to calculate RRFs for Spatial Fields exactly as you would for Point Estimates, except in the case when the minimum number of days threshold cannot be met (MATS would return a -9 value for point estimates).

An example of such a case of where the two RRF calculations differ is when the number of days at or above the Minimum allowable threshold valueis less than the Minimum number of days at or above minimum allowable threshold . In this case, MATS would not calculate an RRF for a Point Estimate. However, if the Backstop minimum threshold for spatial fieldsis set to some value lower than the Minimum allowable threshold value , then MATS could potentially calculate an RRF for all or most grid cells in a Spatial Field. The backstop minimum threshold allows the minimum threshold to be lowered to a value below the Minimum allowable threshold valueuntil the minimum number of days is reached. The backstop threshold is only used for grid cells which do not have enough days to meet the minimum number of days value with the minimum allowable threshold. The backstop threshold does not change the calculation for grid cells that already meet the minimum number of days.

Assume that there are 15 days of data for a grid cell: Baseline day Baseline value Future day Future value

1 67 1 65 2 74 2 73Ozone Analysis: Details

April 2014 Abt Associates Inc. 271 3 70 3 69 4 68 4 66 5 78 5 77 6 67 6 64 7 66 7 63 8 65 8 63 9 63 9 63 10 62 11 61 11 61 10 60 12 60 12 59 13 60 13 57 14 59 14 56 15 57 15 55



### MATS will sort the data from high to low based on the Baseline values: Baseline day Baseline value Future day Future value

5 78 5 77 2 74 2 73 3 70 3 69 4 68 4 66 1 67 1 65 6 67 6 64 7 66 7 63 8 65 8 63 9 63 9 63 10 62 11 61 11 61 10 60 12 60 12 59 13 60 13 57 14 59 14 56 15 57 15 55



### When you compare these sorted data with the Initial threshold valueof 85 ppb, note that there are zero (0) Baseline values at or above this threshold. Since there are fewer days than the ten (10) specified as the Minimum number of days in baseline at or above threshold , MATS will lower the threshold by one ppb, and eventually get to the Minimum allowable threshold valueof 70 ppb. At this point, there are still only three (3) Baseline values (highlighted in yellow) at or above this lower threshold -- still less than the value of ten (10) that specified as theOzone Analysis: Details

April 2014 Abt Associates Inc. 272 

### Minimum number of days in baseline at or above threshold . This fails the test for calculating an RRF for a Point Estimate. However, there is still a possibility that MATS can calculate an RRF for a Spatial Field. MATS just needs to find at least five values MATS will lower the threshold again by one ppb. At a threshold of 68 ppb, there are four (4) days. MATS will lower the threshold again by one ppb. At a value of 67 ppb, there are six (6) days at or above the Backstop minimum threshold for spatial fields

. Baseline day Baseline value Future day Future value

5 78 5 77 2 74 2 73 3 70 3 69 4 68 4 66 1 67 1 65 6 67 6 64 7 66 7 63 8 65 8 63 9 63 9 63 10 62 11 61 11 61 10 60 12 60 12 59 13 60 13 57 14 59 14 56 15 57 15 55



### Since MATS is looking for at least five days, MATS will take these six days (highlighted in yellow) above the Backstop minimum threshold for spatial fields and then calculate separate averages for the Control and Baseline values: Control average = 70.0000 ppb Baseline average = 71.4000 ppb. The RRF equals the ratio of the Control to the Baseline: RRF = 70.0000 / 71.4000 = 0.980 Note that we report the RRF with three digits after the decimal point. The calculation of the Baseline and Control averages does not involve any rounding or truncation.


## 9.4.2 Spatial Gradient Setup In using a spatial gradient to estimate ozone levels, MATS estimates ozone levels in unmonitored locations by using the values of a nearby monitored data scaled by a ratio of model values. The ratio, or spatial gradient, is a mean of model values at the unmonitoredOzone Analysis: Details

April 2014 Abt Associates Inc. 273 

### location over the mean of the model values at a monitor. Note that several "nearby" monitors (and their associated model values) are used in the calculation of ozone values at an unmonitored location. MATS uses a process called Voronoi Neighbor Averaging (VNA) to identify these neighbors, and then takes an inverse distance-weighted average of these monitors. MATS sorts the daily 8-hour maximum ozone values from high to low, averages a certain number of these values (by default the top five), and then uses these averages in the calculation of the spatial gradient. Note that the highest days for Cell A and Cell E are determined independently of each other. If you want to use a different set of days for the gradient adjustment, you can do so with the Start Valueand End Value . MATS assigns an index of value of 1 to the highest daily 8-hour maximum ozone value in each grid cell. The second-highest an index value of 2. And so on. Using the Start Valueand the End Value , you can identify the values that you want to average by using this index.
9.4.2.1 Spatial Gradient Calculation - Example 1 Assume a Start Value of "1" and an End Value of "5":

For this example calculation, assume that we have one monitor and we want to use this monitor to estimate the ozone level at the center of a nearby grid cell. Further assume thatOzone Analysis: Details

April 2014 Abt Associates Inc. 274 

### the monitor resides in grid cell "A" and the we want to estimate the ozone level in grid cell "E". With the default Start Value equal to one (1) and the default End Value, equal to five (5), MATS will average the five highest daily 8-hour maximum ozone values. Note, however, that the highest days for Cell A and Cell E are determined independently of each other. Assume that there are 15 days of data: Day Cell A Day Cell E 1 100 1 68 2 100 2 73 3 98 3 74 4 97 4 78 5 95 5 72 6 95 6 69 7 90 7 77 8 85 8 63 9 84 9 65 10 83 10 61 11 83 11 60 12 83 12 62 13 79 13 58 14 78 14 56 15 78 15 57 

### MATS will sort the data for cell A from high to low. Independently, MATS will also sort the data for Cell E from high to low. In this example, Day 1 has the highest value for cell A, while the highest value for cell E falls on Day 2. Day Cell A Day Cell E 1 100 4 78 2 100 7 77 3 98 3 74 4 97 2 73 5 95 5 72 6 95 6 69 7 90 1 68 8 85 9 65 9 84 8 63 10 83 12 62 11 83 10 61 12 83 11 60 13 79 13 58Ozone Analysis: Details

April 2014 Abt Associates Inc. 275 14 78 15 57 15 78 14 56



### MATS will take the top 5 days (highlighted in yellow) and then calculate separate averages for cell A and cell E: cell E average = 74.8000 ppb cell A average = 98.0000 ppb. The Spatial Gradientequals the ratio of Cell E to Cell A: Spatial Gradient = 74.8000 / 98.0000 = 0.763 Note that we report the Spatial Gradient with three digits after the decimal point. The calculation of the averages does not involve any rounding or truncation.
9.4.2.2 Spatial Gradient Calculation - Example 2 Assume a Start Value of "2" and an End Value of "3":

For this example calculation, assume that we have one monitor and we want to use this monitor to estimate the ozone level at the center of a nearby grid cell. Further assume that the monitor resides in grid cell "A" and the we want to estimate the ozone level in grid cellOzone Analysis: Details

April 2014 Abt Associates Inc. 276 

### "E". With the default Start Value equal to two (2) and the default End Value, equal to three (3), MATS will average the second and third highest daily 8-hour maximum ozone values. Assume that there are 15 days of data: Day Cell A Day Cell E 1 100 1 68 2 100 2 73 3 98 3 74 4 97 4 78 5 95 5 72 6 95 6 69 7 90 7 77 8 85 8 63 9 84 9 65 10 83 10 61 11 83 11 60 12 83 12 62 13 79 13 58 14 78 14 56 15 78 15 57 

### MATS will sort the data for cell A from high to low. Independently, MATS will also sort the data for Cell E from high to low. Day Cell A Day Cell E 1 100 4 78 2 100 7 77 3 98 3 74 4 97 2 73 5 95 5 72 6 95 6 69 7 90 1 68 8 85 9 65 9 84 8 63 10 83 12 62 11 83 10 61 12 83 11 60 13 79 13 58 14 78 15 57 15 78 14 56 

### MATS will take the second and third highest days (highlighted in yellow) and thenOzone Analysis: Details

April 2014 Abt Associates Inc. 277 

### calculate separate averages for cell A and cell E: cell E average = 75.5000 ppb cell A average = 99.0000 ppb. The Spatial Gradientequals the ratio of Cell E to Cell A: Spatial Gradient = 75.5000 / 99.0000 = 0.763 Note that we report the Spatial Gradient with three digits after the decimal point. The calculation of the averages does not involve any rounding or truncation.
9.4.2.3 Spatial Gradient Calculation - Example 3 Assume a Start Value of "4" and an End Value of "4":

For this examplecalculation, assume that we have one monitor and we want to use this monitor to estimate the ozone level at the center of a nearby grid cell. Further assume that the monitor resides in grid cell "A" and the we want to estimate the ozone level in grid cell "E". With the default Start Value equal to four (4) and the default End Value, equal to four (4), MATS will only use the fourth highest daily 8-hour maximum ozone value in each grid cell.Ozone Analysis: Details

April 2014 Abt Associates Inc. 278 

### Assume that there are 15 days of data: Day Cell A Day Cell E 1 100 1 68 2 100 2 73 3 98 3 74 4 97 4 78 5 95 5 72 6 95 6 69 7 90 7 77 8 85 8 63 9 84 9 65 10 83 10 61 11 83 11 60 12 83 12 62 13 79 13 58 14 78 14 56 15 78 15 57 

### MATS will sort the data for cell A from high to low. Independently, MATS will also sort the data for Cell E from high to low. Day Cell A Day Cell E 1 100 4 78 2 100 7 77 3 98 3 74 4 97 2 73 5 95 5 72 6 95 6 69 7 90 1 68 8 85 9 65 9 84 8 63 10 83 12 62 11 83 10 61 12 83 11 60 13 79 13 58 14 78 15 57 15 78 14 56 

### MATS will take the fourth highest day (highlighted in yellow) for cell A and cell E: cell E = 73 ppb cell A = 97 ppb.Ozone Analysis: Details

April 2014 Abt Associates Inc. 279 

### The Spatial Gradientequals the ratio of Cell E to Cell A: Spatial Gradient = 73 / 97 = 0.753 Note that we report the Spatial Gradient with three digits after the decimal point. 

## 9.5 Final Check
The Final Checkwindow verifies the selections that you have made.

Click the button Press here to verify your selections . If there are any errors, MATS will present a message letting you know. For example, if the path to a model file is invalid -- perhaps you misspelled the file name -- you would get the following error:Ozone Analysis: Details

April 2014 Abt Associates Inc. 280 

### After making the necessary correction, click the button Press here to verify your selections

. .

When your window looks like the window above, click either Save Scenario & Runor Save Scenario. Save Scenario & Run will cause MATS to immediately run the scenario.


## 9.5.1 Running MATS in Batch Mode The Save Scenariobutton will save the scenario as a configuration file (.cfg file). The "*.cfg" file will be saved in the .\MATS\output directory. Several .cfg files can be created with the MATS interface and run later in batch mode. To do this, edit the default batch file located in the .\MATS directory. The file "batchmats.bat" should be edited with a text editor to point to the name and location of the .cfg files that will be run in batch mode.

After editing the batchmats.bat file, simply run the .bat file. MATS will start and run in the background.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 281 

## 10 

# Visibility Analysis: Quick Start Tutorial 10
In this tutorial you will forecast visibility levels at Class I Areasin the United States. The steps in this analysis are as follows:

· Step 1. Start MATS . Start the MATS program and choose to do a Visibility analysis.

· Step 2. Output Choice . Choose the output to generate. In this example, you will forecast visibility levels using the new IMPROVE algorithmand model data at the IMPROVE monitors.

· Step 3. Data Input . Choose the data files for input to MATS.

· Step 4. Filtering . Choosethe years of monitor and model data that you want to use, and then choose the particular monitors in these data that you want to include in the analysis.

· Step 5. Final Check . Verify the choices you have made.

· Step 6. Load & Map Results
. Load your results and prepare maps of your forecasts.

· Step 7. Working with Configuration File . Examine the Configuration file that stores the choices that you made underlying your analysis.

Each step is explained in detail below. Additional details are provided in the section Visibility Analysis: Details

. 

## 10.1 Step 1. Start MATS Double-click on the MATS icon on your desktop, and the following window will appear:Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 282 

### Click the Visibility Analysisbutton on the main MATS window. This will bring up the Configuration Managementwindow.

A Configurationallows you to keep track of the choices that you make when using MATS. For example, after generating results in MATS, you can go back, change one of your choices, rerun your analysis, and then see the impact of this change without having to enter in all of your other choices. For this example, we will start with a new Configuration. Choose Create New Configurationand click the Gobutton. This will bring up the Choose Desired Outputwindow. 

## 10.2 Step 2. Output Choice The Choose Desired Output window allows you to choose the output that you would likeVisibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 283 

### to generate. MATS allows you to calculate future year (forecast) visibility levels at Class I Areas

. In the Scenario Namebox type “Tutorial Visibility”

–this will be used to keep track of where your results are stored and the variable names used in your results files. Leave the box checked next to Temporally-adjust visibility levels at Class I Areas. MATS will create forecasts for each Class I Area in your modeling domain. MATS provides two algorithms for calculating visibility -- an " old version " and a " new version " of the IMPROVE visibility algorithm ( see IMPROVE 2006 ) (The old and new versions are discussed in Desired Outputsection of the Visibility Analysis: Details chapter.) Choose the new version. A single IMPROVE monitor is associated with each Class I Area. MATS multiplies the monitor value with a relative response factor (RRF) , which is the the modeled future-year visibility divided the modeled current-year visibility. In calculating the RRF, MATS allows you to use either the model values in the grid cell at the IMPROVE monitor or to use the model values in the grid cell at the Class I Area centroid. Choose the default option of using model values in the grid cell at the monitor. (For additional details see the Desired Outputsection of the Visibility Analysis: Details chapter.) Check the box next to Automatically extract all selected output files . MATS will create a separate folder called "Tutorial Visibility" in the MATS "Output" folder, and then export .CSV files with the results of your analysis. Alternatively, you can export the results from the Output Navigator , but checking this box is a little easier.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 284 

### When your window looks like the window above, click Next . This will bring up the Data Input window. 

## 10.3 Step 3. Data Input
The Data Inputwindow allows you to choose the monitor data and the model data that you want to use. As discussed in more detail in the Visibility Analysis: Details chapter, MATS calculates the ratio of the model data to calculate a relative response factor (RRF) for the 20% best and 20% worst visibility days separately. MATS then multiplies the visibility level measured at the monitor for the best days with the RRF for the best days to calculate a future-year estimate for visibility on the best visibility days. MATS performs an analogous calculation for the worst visibility days. MATS comes loaded with IMPROVE visibility monitorvalues from 2000 through 2010. It also comes loaded with an example model output dataset for visibility for 2002 and 2020. These are the key ingredients for creating your visibility forecasts

. Use the default settings in the Data Inputwindow. The window should look like the following:Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 285 

### Note that MATS gives you the option to use model data in different ways when calculating forecasts at each monitor. The example model datasets are at 36km resolution. Therefore, the default is to use a 3x3 array of model cells aroundeach monitor. This is described in more detail in the Using Model Datasection of the Visibility Analysis: Details chapter

. When your window looks like the window above, click Next . This brings up the visibility Filteringwindow. 

## 10.4 Step 4. Filtering
TheFiltering window has two sets of functions. The first involves identifying the years of monitor and model data that you want to use. The second involves identifying the particular monitors in these data that you want to include in the analysis. Use the default settings pictured in the screenshot below. Choose Visibility Data Years

· Specify the range of visibility monitor data that you want to use. The default is to use all of the available data: 2005 through 2009. (That is, Start Monitor Yearset to 2005and End Monitor Yearset to 2009 .)

· Choose the Base Model Year . This should match the metorological year that is being modeled. It should fall within the range specified by the Start Monitor Year and the EndVisibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 286 

### Monitor Year. The Base Model Yearfor the example dataset is 2007

. Valid Visibility Monitors

· Identify the monitors that you want to include in the analysis. First, specify the Minimum years required for a valid monitor . MATS excludes from the analysis any monitors with fewer than the Minimum years required for a valid monitor . The default value is 3years.



## 10.5 Step 5. Final_Check
The Final Checkwindow verifies the choices that you have made. For example, it makes sure that the paths specified to each of the files used in your Configurationare valid. Click on the Press here to verify selectionsbutton.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 287 

### If you encounter any errors, go back to the choices you have previously made by clicking on the appropriate part ( e.g. , Data Input) of the tree in the left panel, and then make any changes required. When your window looks like the window above, click either Save Scenario & Runor Save Scenario. Save Scenario & Run will cause MATS to immediately run the scenario. A temporary, new Runningtab will appear (in addition to the Start , Map Viewand Output Navigatortabs).Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 288 

### Note that MATS is very computation-intensive, so if you try to work with other programs in addition they may run very slowly. When the calculations are complete, a small window indicating the results are Donewill appear. Click OK

.

After clicking OK , the Output Navigatortab will be active. (The Runningtab will no longer be seen.). MATS will automatically load the output files associated with the .asr configuration that just finished running.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 289 

### The next step ( click here ) shows you how to map your results with the Output Navigator

. For more details on mapping and other aspects of the Output Navigator , there is a separate chapter on the Output Navigator

. 

## 10.6 Step 6. Load and Map Results After generating your results, Output Navigatorcan be used to load and/or map them. If a run just finished, the output files will already be loaded into output navigator. If files from a previous run need to be loaded then click on the Loadbutton and choose the Tutorial Visibility.asr file.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 290 

### Click on the Loadbutton and choose the Tutorial Visibility.asr file.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 291 

### Under Configuration/Log Files , you will see two files:

· Configuration : keeps track of the assumptions that you have made in your analysis.

· Log File : provides information on a variety of technical aspects regarding how a results file (*.ASR) was created. Under Output Filesyou will see:

· Tutorial Visibility - Forecasted Visibility - all design values : baseline and forecasted visibility levels for the best and worst days for each year of the five year base period.

· Tutorial Visibility - Used Model Grid Cells - Base Data : baseline model values for PM species for the grid cells and days used in the RRF calculations.

· Tutorial Visibility - Used Model Grid Cells - Future Data : future-year model values for PM species for the grid cells and days used in the RRF calculations.

· Tutorial Visibility - Forecasted Visibility Data : baseline and forecasted deciview values for the best and worst days (averaged across up to five years). Also includes species-specific relative response factors for the best and worst days.

· Tutorial Visibility - Class 1 Area and IMPROVE Monitor Identifiers and Locations : monitor latitude and longitude.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 292 

### Right-click on the file Tutorial Visibility - Forecasted Visibility Data . This gives you three options: Add to Map , View , and Extract . Choose the Add to Mapoption.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 293 

### This will bring up the Map View

.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 294 

### To view an enlarged map, use the Zoom to an areaTask Bar button on the far left. Choose the Continental US

.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 295 

### The map will then zoom to the Continental US.

To more easily view the location of monitors in particular states, uncheck US Counties using the Standard Layersdrop down menu on the far right of the Task Bar. Your window should look like the following:Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 296 

### Right click on the " Tutorial Visibility - Forecasted Visibility Data " l ayer in the panel on the left side of the window. Choose the Plot Valueoption.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 297 

### This will bring up Shape Class Breakswindow. In the Valuedrop-down list, choose the variable " dv_best " -- this is forecasted visibility design value for the best visibility days in 2015. (Note that the Datebox defaults to the baseline year; in this case 2002 .)

Click Applyand then click Close . This will bring you back to the Map Viewwindow.

Examine the other variables:Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 298 

### dv_worst : forecasted deciview values for 20% worst days; dv_best : forecasted deciview values for 20% best days base_best : baseline design values for best days; base_worst : baseline design values for worst days; rrf_b_crustal, rrf_b_no3, rrf_b_oc, rrf_b_ec, rrf_b_cm, andrrf_b_so4 : relative response factor used to forecast the best visibility days; rrf_w_crustal, rrf_w_no3, rrf_w_oc, rrf_w_ec, rrf_w_cm, andrrf_w_so4 : relative response factor used to forecast the worst visibility days; This is just a brief summary of the mapping possibilities available. For more details, there is a separate chapter on the Map View

. 

## 10.7 Step 7. Working with Configuration File Configurations keep track of the choices that you have made in your analysis. There are two ways that you can access your configuration. First, you can view your configuration using the Output Navigator. Right-click on Configurationand choose View

.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 299 

### This will take you to the Tutorial Visibilityconfiguration that you used to generate your visibility results.

A second way to access your Tutorial Visibility configuration is to go back to the Start window.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 300 

### Click on the Visibility Analysisbutton. This will bring up the Configuration Managementwindow.

Choose Open Existing Configurationand then click the Gobutton. This will bring up the Select a Configurationwindow. Find the Tutorial Visibility.asr file that you generated.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 301 

### Click Openand this will bring you your Tutorial Visibilityconfiguration. Choose the Use model grid cells at Class 1 area centroidoption.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 302 

### MATS will now calculate RRFs using model data located over the center of each Class 1 area, instead of using model data located over the monitor linked to each Class 1 area. To reflect this change in your analysis, change the Scenario Namebox to Tutorial Visibility - Model at Class 1

.Visibility Analysis: Quick Start Tutorial

April 2014 Abt Associates Inc. 303 

### Keep all of the other assumptions the same. At the Filteringwindow, click the Finish button. MATS will generate a new set of results and save them in a file called: Tutorial Visibility - Model at Class 1.asr . You can then view and map your results in the same way as with other results files.Visibility Analysis: Details

April 2014 Abt Associates Inc. 304 

## 11 

# Visibility Analysis: Details 11
MATS can calculate baseline and future-year visibility levels for the best and worst days for Class I Areas-- these estimates are referred to as Point Estimates , as they refer to particular locations. MATS gives you several options for how to generate these estimates, and keeps track of the choices you make with a Configuration

. When you begin the process of generating visibility estimates, MATS provides an option to start a new Configuration or to open an existing Configuration.

Select your option and then click Go

. MATS will then step you through a series of windows with choices for your analysis.

· Choose Desired Output . Choose whether you want to calculate Point Estimatesat IMPROVE monitors or at Class I Area centroids and whether to use the old or new version of the IMPROVE visibility equation.

· Data Input
. Specify the air modeling and monitoring data that you want to use. Specify which model grid cells will be used when calculating RRFs at monitor locations.

· Filtering
. Choose the years of monitoring data. Identify valid monitors.

MATS comes with a set of default choices and an example set of input files. If desired you can use these defaults and skip to the Final Check window and click the Finishbutton to generate your calculations. 

## 11.1 Choose Desired Output
In the Choose Desired Outputwindow, you specify the Scenario Namethat you would like to use, as well as choices regarding how you would like to calculate future year (forecast) visibility levels for Class I Areas. As discussed in the section on Forecasting Visibility , the forecast calculations have a number of steps. At the end of this section, there is an exampleof these calculations. You may use the "old version" or "new version" of the IMPROVE Equation( IMPROVE, 2006 ), which MATS uses to translate PM levels (measured in ug/m3) to visibility levels (measured in extinction or deciviews). You may also choose between using model data

atVisibility Analysis: Details

April 2014 Abt Associates Inc. 305 

### the monitor or model data at the center of the Class I Area. * By checking the box next to Automatically extract all selected output files, MATS will create a separate folder with your chosen Scenario Name in the MATS "Output" folder, and then export .CSV files with the results of your analysis. Alternatively, you can export the results from the Output Navigator , but checking this box is a little easier.

* Monitors assigned to represent a Class I Area are generally close to the Class I Area. However, in some cases, the distance can be substantial. For example, the YELL2 monitor in Wyoming (44.5653 latitude, -110.4002 longitude) is located more than a degree longitude away from the Red Rocks Lake Class I Area (44.64 latitude, -111.78 longitude). By default, MATS uses model data at the monitor. 

## 11.1.1 Scenario Name The Scenario Nameallows you to uniquely identify each analysis that you conduct. It is used in three ways. (1) Results file name . The results file is given the Scenario Name(e.g., Tutorial Visibility.asr). Note that the extension ( .ASR ) is specifically designated just for MATS and can only be used by MATS. (2) Organize output . In the Output folder, MATS will generate a folder using the Scenario Name . MATS will use this folder as a default location for files generated withVisibility Analysis: Details

April 2014 Abt Associates Inc. 306 

### this Scenario Name

.

(3) Output file names . The output files generated will begin with the Scenario Name

.Visibility Analysis: Details

April 2014 Abt Associates Inc. 307 

## 11.1.2 Forecast Visibility at Class I Areas MATS provides a forecast of visibility in Class I Areas . The approach used has the following steps:

· Identify best & worst visibility monitor days in Base Model Year . Use monitored total extinctiondata from a user-specified year to identify the 20 percent best and 20 percent worst visibility days at each Class I area. At this stage MATS is using extinction values (measured in inverse megameters). By the end of this series of calculations, MATS will convert these extinction visibility measures to deciviews

. Note that you specify the particular year, the Base Model Year , from the available monitoring data in the Filteringwindow. MATS labels the year of monitoringdata as the Base Model Year , because this particular year of monitor data matches the baseline model data, specified in the Data Input window.

· Average best & worst baselinemodel days . Using baseline speciated model data (specified in the Data Inputwindow), average the 20 percent best visibility days and then average the 20 percent worst visibility days at each Class I areas (matched with the ambient data). The model data comes into MATS as speciated values measured in ug/m 3 

### . Average these speciated values. When done there will be two averages (one “best” the other “worst”) for each species and these averages will be ug/m 3



### .Visibility Analysis: Details

April 2014 Abt Associates Inc. 308 

### · Average best & worst forecastmodel days . Calculate these same averages for the forecast model data (specified in the Data Input window). That is, identify the same 20 percent best and 20 percent worst visibility days and then average the speciated model data (measured in ug/m 3 

### ). * When done there will be two averages (one “best” the other “worst”) for each species and these averages will be in ug/m 3



### .

· Calculate RRFs . Use the speciated (best & worst) averages from the baseline and forecast model data to calculate two RRFs for each species. That is, there will be one RRF for the 20 percent best visibility days and another for the 20 percent worst visibility days at each Class I area. The “best” RRF is simply the ratio of the baseline “best” average (measured in ug/m 3 

### ) to the control scenario “best” average (measured in ug/m 3 

### ). The “worst” RRF is calculated in an analogous way. An RRF is unitless and there are two for each species.

· Identify best & worst visibility days in other monitored years. Using monitored total extinction, identify the 20 percent best visibility days and the 20 percent worst visibility days from the other available years of monitoring data. The default in MATS is that there should be at least three valid years and one of those years should be the base modeling year (the base meteorological year). (Monitor validity is discussed further in the Valid Visibility Monitors section.) Note that the 20 percent best days will occur on a different set of days for each year; similarly, the 20 percent worst days will occur on a different set of days for each year.

· Multiply RRF with speciated monitor data from each year . Multiply the speciesspecific “best” RRF (unitless) with the “best” daily speciated monitor values (measured in ug/m 3 

### ) from each of the available years. Do analogous calculations for the worst days. When done, there will the original (baseline) monitor values and an analogous set of forecast values (equal to the baseline times the RRF). Note that the RRF is based on best/worst days identified from the Base Model Year

. This same " Base Model Year " RRF is used with all of the valid monitor years. For example, if the Base Model Year were 2001, then the RRF developed from 2001 modeling data will be applied to all valid data in the five year ambient base period.

· Convert ug/m 3

### values to daily extinction values and sum to get total extinction . For each day in each valid monitoryear (for both the baseline and forecast), use either the New IMPROVE equationor the Old IMPROVE equationto convert ug/m 3 

### values to get daily total extinction (measured in inverse megameters). After this calculation there will be a set of total extinction values for the best and worst visibility days in each valid year for both the baseline and the forecast.

· Convert extinction to deciviews . For each valid year in both the baseline and forecast, convert the best & worst daily averages from extinction (inverse megameters) to deciviews (unitless). The formula for this conversion is as follows: Deciviews = 10*ln (extinction/10)

· Average daily best and worst days . For each valid year, average the daily deciviewVisibility Analysis: Details

April 2014 Abt Associates Inc. 309 

### values from the 20 percent best visibility days and calculate the same average for the 20 percent worst visibility days. There will be up to five “best” averages and “worst” total visibility measures (measured in deciviews) for both the baseline and the forecast.

· Calculate final average . Average the valid best/worst yearly visibility measures. When done there will be one “best” value and one “worst” value, measured in deciviews (unitless), for both the baseline and forecast.

* The future days are the same as the base year days. The identification of the 20 percent best and worst is solely based on the base year ambient data. 

### 11.1.2.1 Old IMPROVE Equation The Old IMPROVE equation is as follows: bext = 3*f(RH)*AMM_SO4 + 3*f(RH)*AMM_NO3 + 4*OMC + 10*EC + CRUSTAL + 0.6*CM + RAYLEIGH. where: bext = total extinction (measured in inverse megameters) FRH = term to account for enhancement of light scattering due to hydroscopic growth of suflate and nitrate (unitless) AMM_SO4 = ammonium sulfate (ug/m 3 

### ) AMM_NO3 = ammonium nitrate (ug/m 3 

### ) OMC= organic carbon mass (ug/m 3 

### ) (OC*1.4) EC= elemental carbon (ug/m 3 

### ) CRUSTAL = fine soil (ug/m 3 

### ) CM= coarse particulate matter (ug/m 3 

### ) RAYLEIGH= Rayleigh scattering. Accounts for natural scattering of light by gases in the atmosphere. Assumed to equal 10 inverse megameters at all locations

.Visibility Analysis: Details

April 2014 Abt Associates Inc. 310 

### Example Calculation Old IMPROVE Equation The first column "bext" presents the calculated value given the following data.

11.1.2.2 New IMPROVE Equation The New IMPROVE Equation has a number of additional terms, in relation to the Old IMPROVEequation. In particular, it takes into account the different effects of small and large sulfate, nitrate, and organic carbon particles. A separate equation defining small and large is given below. bext = 2.2*f s 

### (RH)*[SMALL_AMM_SO4] + 4.8*f l 

### (RH)*[LARGE_AMM_SO4]
+ 2.4*f s 

### (RH)*[SMALL_AMM_NO3] + 5.1*f l 

### (RH)*[LARGE_AMM_NO3] + 2.8*[SMALL_OMC] + 6.1*[LARGE_OMC] + 10*EC + CRUSTAL + 0.6*CM + SS_RAYLEIGH + 1.7*f ss 

### (RH)*SEA_SALT
+ 0.33*NO2. where: bext = total extinction (measured in inverse megameters) f s 

### (RH) = term to account for enhancement of light scattering due to hydroscopic growth of small ammonium nitrate and ammonium sulfate (unitless) f l 

### (RH) = term to account for enhancement of light scattering due to hydroscopic growth of large ammonium nitrate and ammonium sulfate (unitless) SMALL_AMM_SO4 = small ammonium sulfate (ug/m 3 

### )Visibility Analysis: Details

April 2014 Abt Associates Inc. 311 

### LARGE_AMM_SO4 = large ammonium sulfate (ug/m 3 

### ) SMALL_AMM_NO3 = small ammonium nitrate (ug/m 3 

### ) LARGE_AMM_NO3 = large ammonium nitrate (ug/m 3 

### ) SMALL_OMC= small organic carbon mass (ug/m 3 

### ) (OC*1.8) LARGE_OMC= large organic carbon mass (ug/m 3 

### ) (OC*1.8) EC= elemental carbon (ug/m 3 

### ) CRUSTAL= fine soil (ug/m 3 

### ) CM= coarse particulate matter (ug/m 3 

### ) SS_RAYLEIGH = Site-specific Rayleigh scattering (inverse megameters) f ss 

### (RH) = term to account for enhancement of light scattering due to hydroscopic growth of sea salt (unitless) SEA_SALT = Sea salt (ug/m 3 

### ) NO2 = Nitrogen dioxide levels (parts per billion). This term is assumed to be zero. The apportionment of the total concentration of sulfate compounds into the concentrations of the small and large size fractions is accomplished using the following equations:

[ Large Sulfate] = [Total Sulfate]/20 ug/m 3 

### x [Total Sulfate], for [Total Sulfate] < 20 ug/m 3 

### [Large Sulfate] = [Total Sulfate], for [Total Sulfate] 320 ug/m 3 

### [Small Sulfate] = [Total Sulfate] - [Large Sulfate]
The same equations are used to apportion total nitrate and total organic mass concentrations into the small and large size fractions.

Example Calculation New IMPROVE Equation The first column "bext" presents the calculated value given the following data.Visibility Analysis: Details

April 2014 Abt Associates Inc. 312 

### 11.1.2.3 Choose Model Grid Cell The model data are used to calculate an RRF for each species for both the best and worst visibility days. The RRF is the ratio of future-year modeled visibility levels over baseline modeled visibility levels. When forecasting visibility, MATS allows you to choose whether the RRF will be calculated with model data from the grid cell containing the monitor or the centroid of the Class I Area. The representative IMPROVE monitor assignments are taken from Appendix A, Table A-2 of "Guidance for Tracking Progress Under the Regional Haze Rule" http://www.epa.gov/ttn/oarpg/t1/memoranda/rh_tpurhr_gd.pdf. Monitors assigned to represent a Class I Area are generally close to the Class I Area. However, in some cases, this distance can be substantial. For example, the YELL2 monitor in Wyoming (44.5653 latitude, -110.4002 longitude) is located more than a degree longitude away from the Red Rocks Lake Class I Area (44.64 latitude, -111.78 longitude). By default, MATS uses model data at the monitor.


## 11.1.3 Visibility Output Variable Description MATS generates five output files:Visibility Analysis: Details

April 2014 Abt Associates Inc. 313 

### · Visibility forecast (average of design values) . (Up to) five year average of forecasted and base-year average visibility. When you have specified the option Use model grid cells at monitor , name of this file is "Forecasted Visibility Data.csv" with the Scenario Nameappended at the beginning (e.g., "Tutorial Visibility - Forecasted Visibility Data. csv"). When you have specified the option Use model grid cells at Class 1 area centroid , name of this file changes to "Forecasted Visibility Data for Class 1 Areas.csv" plus the Scenario Name (e.g., "Example Visibility - Forecasted Visibility Data for Class 1 Areas.csv").

· Visibility forecast (all design values) . Forecasted and base-year values for individual years. (The forecast is based on The name of this file is "Forecasted Visibility - all design values.csv" plus the Scenario Name (e.g., "Tutorial Visibility - Forecasted Visibility - all design values.csv").

· Class I areas and the monitors . Contains a list of all of the Class I areas and the monitors assigned to each. The name of this file is "Class 1 Area and IMPROVE Monitor Identifiers and Locations.csv" plus the Scenario Name (e.g., "Tutorial Visibility - Class 1 Area and IMPROVE Monitor Identifiers and Locations.csv").

· Base-year model data used. The name of this file is: "Used Model Grid Cells - Base Data.csv" plus the Scenario Name (e.g., "Tutorial Visibility - Used Model Grid Cells - Base Data.csv"). This file contains the base year model values for PM species for the grid cells and days used in the RRF calculations.

· Future-year model data used. The format for this file is the same as for the base-year. The name of this file is: "Used Model Grid Cells - Future Data.csv" plus the Scenario Name (e.g., "Tutorial Visibility - Used Model Grid Cells - Future Data.csv"). This file contains the future year model values for PM species for the grid cells and days used in the RRF calculations. The following sub-sections describe the variables in each file.
11.1.3.1 Forecasted Visibility Data.csv The table below describes the variables in the output file. Note that the output data includes a large number of variables, so in the sample output below we have divided the variables into two blocks. In a file actually generated by MATS, these two blocks would be combined. Note also that the variables output by MATS depend on whether you have specified using model dataat the monitor or model data at the center of the Class I Area. This is detailed in the description table below.
Variable Description _id Site ID _type Leave blank date Meteorological modeling year (used to identify the 20% best and worst days from the ambient data)Visibility Analysis: Details

April 2014 Abt Associates Inc. 314 dv_best Forecasted (future year) best visibility [up to five year average] (in deciviews) dv_worst Forecasted (future year) worst visibility [up to five year average] base_best Base-year best visibility [up to five year average] base_worst Base-year worst visibility [up to five year average] rrf_b_crustal Relative response factor (RRF) for crustal matter on the best visibility days rrf_b_no3 RRF for nitrate on the best visibility days rrf_b_oc RRF for organic mass on the best visibility days rrf_b_ec RRF for elemental carbon on the best visibility days rrf_b_cm RRF for coarse matter (PM10 minus PM2.5) on the best visibility days rrf_b_so4 RRF for sulfate on the best visibility days rrf_w_crustal RRF for crustal matter on the worst visibility days rrf_w_no3 RRF for nitrate on the worst visibility days rrf_w_oc RRF for organic mass on the worst visibility days rrf_w_ec RRF for elemental carbon on the worst visibility days rrf_w_cm RRF for coarse matter (PM10 minus PM2.5) on the worst visibility days rrf_w_so4 RRF for sulfate on the worst visibility days monitor_gridcell Identifier for grid cell closest to monitor. (This variable only appears if you specified the Use model grid cell at monitoroption.) class_i_gridcell Identifier for grid cell closest to Class 1 area. (This variable only appears if you specified the Use model grid cell at Class 1 area centroid option.) gridcell_lat Centroid latitude in decimal degrees of grid cell used in calculation. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. gridcell_long Centroid longitude in decimal degrees of grid cell used in calculation. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_lat Monitor latitude. (This variable only appears if you specified the Use model grid cell at monitoroption.) class_i_lat Class 1 area centroid latitude. (This variable only appears if you specified the Use model grid cell at Class 1 area centroid option.) monitor_long Monitor longitude. (This variable only appears if you specified the Use model grid cell at monitoroption.) class_i_long Class 1 area centroid longitude. (This variable only appears if you specified the Use model grid cell at Class 1 area centroid option.)



### 11.1.3.2 Forecasted Visibility - all design values.csv The table below describes the variables in the output file. Note that the variables output by MATS depend on whether you have specified using model data at the monitor or model data at the center of the Class I Area. This is detailed in the description table below.
Variable Description _id Site ID _type Leave blankVisibility Analysis: Details

April 2014 Abt Associates Inc. 315 date Base year of monitoring data dv_best Forecasted (future year) best visibility (in deciviews) dv_worst Forecasted (future year) worst visibility base_best Base-year best visibility base_worst Base-year worst visibility monitor_gridce ll Identifier for grid cell closest to monitor. (This variable only appears if you specified the Use model grid cell at monitoroption.) class_i_gridcel l Identifier for grid cell closest to Class 1 area. (This variable only appears if you specified the Use model grid cell at Class 1 area centroid option.) gridcell_lat Centroid latitude in decimal degrees of grid cell used in calculation. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. gridcell_long Centroid longitude in decimal degrees of grid cell used in calculation. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. monitor_lat Monitor latitude. (This variable only appears if you specified the Use model grid cell at monitoroption.) class_i_lat Class 1 area centroid latitude. (This variable only appears if you specified the Use model grid cell at Class 1 area centroid option.) monitor_long Monitor longitude. (This variable only appears if you specified the Use model grid cell at monitoroption.) class_i_long Class 1 area centroid longitude. (This variable only appears if you specified the Use model grid cell at Class 1 area centroid option.)



### 11.1.3.3 Class 1 Area and IMPROVE Monitor Identifiers and Locations.csv The table below describes the variables in the output file. Note that the output data includes a number of variables, so in the sample output below we have divided the variables into two blocks. In a file actually generated by MATS, these two blocks would be combined.
Variable Description _id Class I area site ID _type Leave blank. _class_i_name Class 1 area name class_i_state State of Class 1 area class_i_lat Latitude in decimal degrees of Class 1 area centroid class_i_long Longitude in decimal degrees of Class 1 area centroid class_i_gridcell Identifier of grid cell closest to the Class 1 area centroid date Meteorological modeling year _monitor_id IMPROVE site code (either at Class I area or a representative site) monitor_lat IMPROVE Monitor latitude monitor_long IMPROVE Monitor longitude monitor_gridcell Identifier of grid cell closest to the monitorVisibility Analysis: Details

April 2014 Abt Associates Inc. 316 

### 11.1.3.4 Used Model Grid Cells - Base/Future Data.csv The table below describes the variables in the output file.
Variable Description _id The ID is a unique name for each monitor in a particular location. The default value is the column identifier multiplied by 1000 plus the row. (This is a character variable.) _type Leave blank gridcell_lat Latitude at the grid cell centroid in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. gridcell_long Longitude at the grid cell centroid in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. date Date of daily average model value with YYYYMMDD format (This is a numeric variable) cm Coarse PM (ug/m3) crustal Crustal PM so4 Sulfate PM
ec Elemental Carbon no3 Nitrate PM
oc Organic carbon PM _visibility_rank worst = 20% worst days used in rrf calculation; best = 20% best days used in rrf calculation 

## 11.2 Data Input
In the Data Inputwindow, you need to specify the monitor data and model data that you want to use. MATS comes with monitor and model data. Alternatively, you can add your own, following the monitor and model format described below. In addition, you need to specify how MATS will evaluate the model data when calculating RRFs

.Visibility Analysis: Details

April 2014 Abt Associates Inc. 317 

## 11.2.1 Monitor Data Input Daily monitor data, with concentration (ug/m3) and visibility (inverse megameters) measures for each species, are available from the VIEWS website http://vista.cira.colostate.edu/views/

. * As described in the Forecasting Visibilitysection, these monitor data are used to: (1) identify the 20 percent best and worst visibility days for a given year, and (2) calculate the 5-year baseline conditions. Note that one IMPROVE monitor is associated with each Class I site, and the calculated visibility for the IMPROVE site is assumed to representative of the Class I site. MATS comes with a default "linkage" databasethat provides the cross-walk that MATS uses for IMPROVE monitors and Class I Areas. The tables in the next sub-sections present the old equation and new equationvariable names and descriptions downloaded from the VIEWS website and the variable names used in MATS. The format the data read into MATS is also included. By default, MATS includes species concentrations (measured in ug/m3) as well as extinction estimates (measured in inverse megameters) and deciview values. MATS uses the concentration estimates. In particular, it uses the variables: AMM_SO4, AMM_NO3, OMC, EC, CRUSTAL, and CM. The variable GOOD_YEAR indicates whether a particular monitor should be used for a given year. A value of “1" means the monitor can be used, and a value of “0" means that the monitor should be dropped for the year.Visibility Analysis: Details

April 2014 Abt Associates Inc. 318 

### The variable GROUP identifies the percentile for the overall visibility level for a particular day. A value of “90" means that the particular day is among the 20 percent worst days for the year. A value of “10" means that the particular day is among the 20 percent best days for that year. (Days with other GROUP values are not needed) There are a number of extra variables in the ambient data input file that are not directly used by MATS (such as extinction values). The additional data can be used to QA MATS output or for additional data analysis.

* The Visibility Information Exchange Web System (VIEWS) is an online exchange of air quality data, research, and ideas designed to understand the effects of air pollution on visibility and to support the Regional Haze Rule enacted by the U.S. Environmental Protection Agency (EPA) to reduce regional haze and improve visibility in national parks and wilderness areas. http://vista.cira.colostate.edu/views/



### 11.2.1.1 Monitor Data Description (Old Equation) The monitor data for the old IMPROVE algorithm includes a large number of variables, so in the sample format below we have only a portion of the variables listed. The table below has a complete listing of the variables. The variables in boldare required variables on the input file. The additional variables are provided for QA purposes and are optional. Visibility Monitor Data Format (Old Algorithm)

Visibility Monitor Data Variables and Descriptions (Old Algorithm) [Variables in bold are required]
Variable Description _ID IMPROVE site code _TYPE Leave blank LAT Latitude in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. LONG Longitude in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. DATE Date of daily average ambient data with YYYYMMDD format (This is aVisibility Analysis: Details

April 2014 Abt Associates Inc. 319 numeric variable) FRH Monthly climatological relative humidity adjustment factor PM25 Measured PM2.5 mass (ug/m3) CRUSTAL Crustal mass ( 2.2 ×[Al] + 2.49 ×[Si] + 1.63 ×[Ca] + 2.42 ×[Fe] + 1.94 ×[Ti]) AMM_NO3 Ammonium nitrate mass (NO3*1.29) OMC Organic carbon mass (OC*1.4) EC Elemental carbon PM10 PM10 mass CM Coarse mass (PM10 minus PM2.5) AMM_SO4 Ammonium sulfate (S*4.125) E_AMM_SO4 Ammonimum sulfate extinction (Mm-1) E_AMM_NO3 Ammonimum nitrate extinction E_OMC Organic mass extinction E_EC Elemental carbon extinction E_CRUSTAL Crustal extinction E_CM Coarse mass (PM10 minus PM2.5) extinction TBEXT Total bext (includes 10 Mm-1 for Rayleigh scattering) DV Deciviews (calculated from Total bext) GOOD_YEAR Denotes complete data for the year (1= all quarters >75% completeness, 0= incomplete) GROUP 90= 20% worst days and 10= 20% best days for each year (if good_year= 1) POSSIBLE_NDAYS Possible samples in quarter NDAYS Actual complete samples per quarter
COMPLETE_QUAR TER Quarter completeness (1= complete, 0= incomplete)

SF Sulfur concentration (used to calculate ammonium sulfate) SO4F Sulfate concentration (may be used as a backup in case S is missing)


### Note : Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.)

11.2.1.2 Monitor Data Description (New Equation) The monitor data for the new IMPROVE algorithm includes a large number of variables, so in the sample format below we have only a portion of the variables listed. The table below has a complete listing of the variables. The variables in boldare required variables on the input file. The additional variables are provided for QA purposes and are optional. Note that sea salt mass is optional, but is used in the visibility calculations if provided. Visibility Monitor Data Format (New Algorithm)Visibility Analysis: Details

April 2014 Abt Associates Inc. 320 

### Visibility Monitor Data Variables and Descriptions (New Algorithm) [Variables in bold are required]

Variable Description _ID IMPROVE site code _TYPE Leave blank LAT Latitude in decimal degrees. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative. LONG Longitude in decimal degrees. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative. DATE Date of daily average ambient data with YYYYMMDD format (This is a numeric variable) FRH Monthly climatological relative humidity adjustment factor FSRH Monthly climatological relative humidity adjustment factor - small sulfate and nitrate particles FLRH Monthly climatological relative humidity adjustment factor - large sulfate and nitrate particles FSSRH Monthly climatological relative humidity adjustment factor - sea salt SS_RAYLEIGH Site-specific Rayleigh scattering (Mm-1) PM25 Measured PM2.5 mass (ug/m3) SEA_SALT Sea salt mass CRUSTAL Crustal mass ( 2.2 ×[Al] + 2.49 ×[Si] + 1.63 ×[Ca] + 2.42 ×[Fe] + 1.94 ×[Ti]) AMM_NO3 Ammonium nitrate mass (NO3*1.29) OMC Organic carbon mass (OC*1.8) EC Elemental carbon PM10 PM10 mass CM Coarse mass (PM10 minus PM2.5) AMM_SO4 Ammonium sulfate (S*4.125) LARGE_OMC Large organic mass SMALL_OMC Small organic mass LARGE_AMM_SO4 Large ammonium sulfate SMALL_AMM_SO4 Small ammonium sulfate LARGE_AMM_NO3 Large ammonium nitrateVisibility Analysis: Details

April 2014 Abt Associates Inc. 321 SMALL_AMM_NO3 Small ammonium nitrate E_AMM_SO4 Ammonimum sulfate extinction (Mm-1) E_AMM_NO3 Ammonimum nitrate extinction E_OMC Organic mass extinction E_EC Elemental carbon extinction E_CRUSTAL Crustal extinction E_CM Coarse mass (PM10 minus PM2.5) extinction E_SEA_SALT Sea salt extinction TBEXT Total bext (includes site specific Rayleigh scattering) DV Deciviews (calculated from Total bext) GOOD_YEAR Denotes complete data for the year (1= all quarters >75% completeness, 0= incomplete) GROUP 90= 20% worst days and 10= 20% best days for each year (if good_year= 1) POSSIBLE_NDAYS Possible samples in quarter NDAYS Actual complete samples per quarter COMPLETE_QUAR TER Quarter completeness (1= complete, 0= incomplete) SF Sulfur concentration (used to calculate ammonium sulfate) SO4F Sulfate concentration (may be used as a backup in case S is missing)


### Note: Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.)
11.2.1.3 Linkage between Monitors & Class I Areas MATS comes with a default database that provides the linkage between IMPROVE monitors and Class I Areas. The file is called "156-Class I-coordinates-all site names.csv". The format of the file and the variable descriptions are as follows:

Format for File Linking IMPROVE Monitors and Class I AreasVisibility Analysis: Details

April 2014 Abt Associates Inc. 322 

### Variables and Descriptions for File Linking IMPROVE Monitors and Class I Areas
Var Name Description (variable type) _MONITOR_ID IMPROVE monitor identification code (text)
MonLAT IMPROVE monitor latitude (numeric)
MonLONG IMPROVE monitor longitude (numeric) _CLASS_I_NAME Name of Class I Area (text) _ID Class I Area identification code (text) _STATE_ID State in which Class I Area is located (text)
LAT Class I Area centroid latitude (numeric)
LONG Class I Area centroid longitude (numeric)

Note : Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.)


## 11.2.2 Model Data Input The model data for the 20 percent best and worst visibility days are used to calculate relative response factors (RRFs), which provide an estimate of the relative change in visibility from the baseline conditions to a future year. Recall from forecast stepsthat the monitor data are used to identify the best and worst days. Not the model data. MATS will match the best and worst measured days to the correct modeled days, by date. The model data input to MATS is in terms of PM species concentrations (measured in ug/m 3 

### ). The following exhibits provide an example of the model data format and a description of the variables. Note that the first line of the data file gives the frequency of the data. In this case, daily data. The second line gives the variables names. The data begins on the third line. Each data line represents a daily observation. Format for Daily PM Model DataVisibility Analysis: Details

April 2014 Abt Associates Inc. 323 

### Visibility Model Data Variable Descriptions
Variable Description _ID The ID is a unique number for each model grid cell in the air quality model domain. It is generally based on the column and row identifiers from the air quality modeling domain. The default convention is to calculate the ID by multiplying the column identifier by one thousand (1000) and adding the row identifier. (This is a character variable.) _TYPE Leave blank LAT Latitude in decimal degrees of the center of each grid cell. Values in the northern hemisphere are positive, and those in the southern hemisphere are negative.

LONG Longitude in decimal degrees of the center of each grid cell. Values in the eastern hemisphere are positive, and those in the western hemisphere (e.g., United States) are negative.
DATE Date of daily average model value with YYYYMMDD format (This is a numeric variable) CM Coarse PM (ug/m3) CRUSTAL Crustal PM SO4 Sulfate PM EC Elemental carbon NO3 Nitrate PM OC Organic mass PM


### Note: Character variables have names that begin with an underscore ( i.e. , "_"), and the character values used can be kept with or without quotes. (If a character variable has an embedded space, such as might occur with the name of a location, then use quotes.) Finally, note that the species variables used by MATS do not exactly correspond to theVisibility Analysis: Details

April 2014 Abt Associates Inc. 324 

### speciated monitor data inputavailable from the VIEWS website. The following exhibit presents the correspondence used by MATS.
Monitor Data Variable Name (from Views) New Variable Name (used within MATS)
Soil CRUSTAL Amm_NO3 AMM_NO3
OMC OMC
LAC EC
CM CM Amm_SO4 AMM_SO4 

### Regardless of the species names used by the air quality model, the model output variables should be changed to the MATS variable names when creating MATS input files.

11.2.2.1 Using Model Data for Temporal Adjustment Relative response factors (RRFs) are calculated for each species: sulfate, nitrate, EC, OMC, Crustal, and Coarse Matter (CM), by taking the ratio of the average of the 20 percent best (or worst) days in the future to the average of the 20 percent best (or worst) days in the baseline. For example, when calculating the sulfate RRF for the 20 percent best days, MATS does the following calculation:

where: j = Class I area i = day identifier n = number of 20 percent best visibility days Sulfate = modeled sulfate concentration (in ug/m 3 

### ) on best visibility days. When identifying the model data for this calculation, MATS first determines whether you want to use model values located at the monitor or at the centroid of the Class I Area. You choose the desired location (monitor or cell centroid) in the Choose Desired Output window. In addition, you need to specify how many cells around the desired location youVisibility Analysis: Details

April 2014 Abt Associates Inc. 325 

### want to use in the calculation ( 1x1 matrix, 3x3matrix, etc), and whether you want to use the maximum or the mean of the model cells.

In the case of a 3x3matrix with Meanspecified , MATS identifies the speciated model values (measured in ug/m 3 

### ) from among the nine “nearby” grid cells for each day for each Class I Area. In the typical case, where there are 365 days of model outputs, MATS will generate 365 daily values. MATS will do this calculation separately for each species for both the baseline and future-year scenarios. The Guidance Document recommends using the Meanof model values when calculating the RRF. Next there is a recommended exampleof how MATS calculates the RRF using the Meanfor a 3x3matrix. (An example with the Maximum is also provided, however this is not the recommended approach for visibility calculations.)Visibility Analysis: Details

April 2014 Abt Associates Inc. 326 RRF Calculation - Example with Mean 

### The Guidance Document recommends using the Meanof the model values. In the case of
a 3x3matrix with Meanspecified, MATS averages the speciated model values (measured in ug/m 3 

### ) from the nine “nearby” grid cells for each day for each Class I Area. Assume there are eight best visibility days with the following modeled sulfate values in the baseline . MATS would average the values for each day. Best Days Cell 1 Cell 2 Cell 3 Cell 4 Cell 5 Cell 6 Cell 7 Cell 8 Cell 9 Mean 1 1.795 1.812 1.299 1.609 1.612 1.250 1.692 0.570 1.347 1.443 2 0.164 1.556 1.205 0.270 1.940 1.065 1.156 1.620 1.786 1.196 3 1.709 0.273 1.304 1.213 1.177 1.104 0.368 1.817 1.377 1.149 4 1.119 1.322 1.778 1.154 1.503 1.511 1.251 1.939 0.474 1.339 5 1.910 1.648 1.012 1.635 1.912 1.587 1.508 1.723 1.611 1.616 6 1.490 1.204 1.997 0.989 1.832 0.064 1.469 1.634 1.470 1.350 7 1.136 1.886 1.131 1.282 1.957 1.047 1.335 0.045 1.279 1.233 8 1.304 1.217 1.738 1.243 1.370 1.802 1.374 1.736 1.196 1.442 

### Assume there are eight best visibility days with the following modeled sulfate values in the forecast . Again, MATS would average the values for each day. Best Days Cell 1 Cell 2 Cell 3 Cell 4 Cell 5 Cell 6 Cell 7 Cell 8 Cell 9 Max 1 1.789 1.715 1.209 1.560 1.562 1.224 1.492 0.489 1.148 1.354 2 0.137 1.512 1.162 0.181 1.939 1.022 1.113 1.541 1.593 1.133Visibility Analysis: Details

April 2014 Abt Associates Inc. 327 3 1.695 0.208 1.254 1.198 1.133 1.102 0.200 1.244 1.235 1.030 4 1.090 1.251 1.627 1.126 1.470 1.468 1.120 1.877 0.325 1.262 5 1.815 1.552 0.974 1.549 1.594 1.546 1.407 1.707 1.591 1.526 6 1.327 1.167 1.880 0.957 1.756 0.000 1.318 1.590 1.392 1.265 7 0.989 1.805 1.028 1.212 1.820 1.010 1.183 0.042 1.236 1.147 8 1.127 1.183 1.673 1.238 1.291 1.753 1.220 1.717 1.004 1.356 

### The average across the daily means for the baseline is 1.346 ug/m3. The average of the forecast cells is 1.259. The sulfate RRF would then be calculated as: RRF = 1.259 / 1.346 = 0.935. A similar process occurs for the other species. The end result is 12 RRFs -- two for each of the six species ( i.e. , sulfate, nitrate, elemental carbon, organic carbon, crustal, and ammonium). RRF Calculation - Example with Maximum 

### The Modeling Guidance Document recommends using the Meanof the model values for visibility calculations. The example below, shows the calculations that would be involved if the Maximumwere chosen. In the case of a 3x3matrix with Maximumspecified, MATS identifies identify the highest speciated model values (measured in ug/m 3 

### ) from among the nine “nearby” grid cells for each day for each Class I Area. Assume there are eight best visibility days with the following modeled sulfate values in the baseline : Best Days Cell 1 Cell 2 Cell 3 Cell 4 Cell 5 Cell 6 Cell 7 Cell 8 Cell 9 1 1.795 1.812 1.299 1.609 1.612 1.250 1.692 0.570 1.347 2 0.164 1.556 1.205 0.270 1.940 1.065 1.156 1.620 1.786 3 1.709 0.273 1.304 1.213 1.177 1.104 0.368 1.817 1.377 4 1.119 1.322 1.778 1.154 1.503 1.511 1.251 1.939 0.474 5 1.910 1.648 1.012 1.635 1.912 1.587 1.508 1.723 1.611 6 1.490 1.204 1.997 0.989 1.832 0.064 1.469 1.634 1.470 7 1.136 1.886 1.131 1.282 1.957 1.047 1.335 0.045 1.279 8 1.304 1.217 1.738 1.243 1.370 1.802 1.374 1.736 1.196 

### MATS would choose the cells highlighted in orange: Best Days Cell 1 Cell 2 Cell 3 Cell 4 Cell 5 Cell 6 Cell 7 Cell 8 Cell 9 1 1.795 1.812 1.299 1.609 1.612 1.250 1.692 0.570 1.347 2 0.164 1.556 1.205 0.270 1.940 1.065 1.156 1.620 1.786 3 1.709 0.273 1.304 1.213 1.177 1.104 0.368 1.817 1.377 4 1.119 1.322 1.778 1.154 1.503 1.511 1.251 1.939 0.474 5 1.910 1.648 1.012 1.635 1.912 1.587 1.508 1.723 1.611 6 1.490 1.204 1.997 0.989 1.832 0.064 1.469 1.634 1.470 7 1.136 1.886 1.131 1.282 1.957 1.047 1.335 0.045 1.279 8 1.304 1.217 1.738 1.243 1.370 1.802 1.374 1.736 1.196Visibility Analysis: Details

April 2014 Abt Associates Inc. 328 

### Assume there are eight best visibility days with the following modeled sulfate values in the forecast : Best Days Cell 1 Cell 2 Cell 3 Cell 4 Cell 5 Cell 6 Cell 7 Cell 8 Cell 9 1 1.789 1.715 1.209 1.560 1.562 1.224 1.492 0.489 1.148 2 0.137 1.512 1.162 0.181 1.939 1.022 1.113 1.541 1.593 3 1.695 0.208 1.254 1.198 1.133 1.102 0.200 1.744 1.235 4 1.090 1.251 1.627 1.126 1.470 1.468 1.120 1.877 0.325 5 1.815 1.552 0.974 1.549 1.894 1.546 1.407 1.707 1.591 6 1.327 1.167 1.880 0.957 1.756 0.000 1.318 1.590 1.392 7 0.989 1.805 1.028 1.212 1.820 1.010 1.183 0.042 1.236 8 1.127 1.183 1.673 1.238 1.291 1.753 1.220 1.717 1.004 

### MATS would choose the cells highlighted in orange. Note that the cells chosen for the forecast can differ from the cells chosen for the baseline. Best Days Cell 1 Cell 2 Cell 3 Cell 4 Cell 5 Cell 6 Cell 7 Cell 8 Cell 9 1 1.789 1.715 1.209 1.560 1.562 1.224 1.492 0.489 1.148 2 0.137 1.512 1.162 0.181 1.939 1.022 1.113 1.541 1.593 3 1.695 0.208 1.254 1.198 1.133 1.102 0.200 1.244 1.235 4 1.090 1.251 1.627 1.126 1.470 1.468 1.120 1.877 0.325 5 1.815 1.552 0.974 1.549 1.594 1.546 1.407 1.707 1.591 6 1.327 1.167 1.880 0.957 1.756 0.000 1.318 1.590 1.392 7 0.989 1.805 1.028 1.212 1.820 1.010 1.183 0.042 1.236 8 1.127 1.183 1.673 1.238 1.291 1.753 1.220 1.717 1.004 

### The average of the best sulfate days chosen from the baseline cells is 1.897 ug/m3. The average of the forecast cells is 1.821. The sulfate RRF would then be calculated as: RRF = 1.821 / 1.897 = 0.960. A similar (independent) process occurs for the other species. The particular cells chosen for sulfate may be quite different from the cells chosen for, say, nitrate. Continuing with the example you might have the following pattern for baseline: Best Days Cell 1 Cell 2 Cell 3 Cell 4 Cell 5 Cell 6 Cell 7 Cell 8 Cell 9 1 0.071 0.133 0.620 0.788 0.808 0.964 0.763 0.938 0.158 2 0.561 0.891 0.105 0.689 0.695 0.302 0.523 0.209 0.485 3 0.005 0.384 0.604 0.077 0.545 0.046 0.177 0.664 0.821 4 0.926 0.651 0.111 0.334 0.887 0.548 0.447 0.547 0.730 5 0.630 0.995 0.769 0.888 0.379 0.121 0.779 0.130 0.558 6 0.700 0.761 0.993 0.556 0.659 0.877 0.761 0.474 0.821 7 0.074 0.189 0.619 0.987 0.279 0.757 0.470 0.189 0.701 8 0.848 0.100 0.964 0.535 0.566 0.315 0.440 0.011 0.852 

### And the following pattern for the forecast:Visibility Analysis: Details

April 2014 Abt Associates Inc. 329 Best Days Cell 1 Cell 2 Cell 3 Cell 4 Cell 5 Cell 6 Cell 7 Cell 8 Cell 9 1 0.068 0.122 0.556 0.711 0.766 0.594 0.653 0.877 0.152 2 0.514 0.515 0.092 0.615 0.687 0.283 0.460 0.198 0.479 3 0.004 0.380 0.513 0.076 0.504 0.044 0.175 0.591 0.801 4 0.769 0.581 0.099 0.327 0.852 0.537 0.416 0.482 0.719 5 0.563 0.940 0.673 0.859 0.374 0.113 0.685 0.123 0.505 6 0.610 0.694 0.910 0.514 0.621 0.828 0.649 0.438 0.794 7 0.072 0.179 0.597 0.954 0.244 0.701 0.428 0.176 0.695 8 0.837 0.090 0.940 0.522 0.500 0.295 0.434 0.011 0.809 

### The end result is 12 RRFs -- two for each of the six species ( i.e. , sulfate, nitrate, elemental carbon, organic carbon, crustal, and ammonium). 

## 11.3 Filtering MATS loads in the monitor data that you have specified in Data Inputwindow, and then in the Filteringwindow MATS presents the available years of monitor data for your analysis. You specify a range of years with the Start Monitor Yearand End Monitor Year drop-down menus. Using the Base Model Yeardrop-down menu, you can also specify the year that you want to use to determine the "best" and "worst" monitor days. The Base Model Yearneeds to fall within the range specified by the Start Monitor Yearand End Monitor Year . Once you have specified the Base Model Year , MATS will then identify and save for each monitor the particular dates during this year that registered the best and worst visibility days. These dates are then used to identify the model values used in the calculation of RRFs for the temporal adjustment, as seen in the Examplein the Model Data Input section. Given a particular range of years that you have chosen, you can also specify the criteria for a monitor to be included in the analysis. With the Minimum years required for a valid monitorbox, you specify the minimum number of years of data that a monitor must have ( e.g. , three years).Visibility Analysis: Details

April 2014 Abt Associates Inc. 330 

## 11.3.1 Example Valid Visibility Monitors Using the Maximum Distance from Domain , you can choose the maximum distance that a monitor (or Class I Area centroid) can be from the nearest model grid cell centroid. Whether you calculate the distance from a monitoror a Class I Area centroid depends on whether you have specified Use model grid cells at monitoror Use model grid cells at Class I area centroid

.Visibility Analysis: Details

April 2014 Abt Associates Inc. 331 

### Example 1 Assume you have chosen Use model grid cells at monitor . If you have set the Maximum Distance from Domainto 25 , and a monitor is more than 25 kilometers from the nearest model grid cell centroid, then a forecast is not generated for this particular monitor. And by extension, a forecast is not generated for the Class I Areas that are associated with this particular monitor. Recall from the section on the Linkage between Monitors and Class I Areasthat more than one Class I Area may be linked to a monitor. Highlighted in yellow below are some examples of monitors associated with more than Class I Area. For example, if the CHIR1 monitor is more than 25 kilometers from the nearest model grid cell centroid, then no forecasts would be generated for the three Class I Areas associated with this monitor ( i.e. , Chiricahua NM, Chiricahua Wilderness, and Galiuro Wilderness). _MONITOR _ID MonLAT MonLONG _CLASS_I_NAME _ID _STATE_

ID LAT LONG ACAD1 44.377 -68.261 Acadia NP ACAD ME 44.35 -68.24 AGTI1 33.464 -116.971 Agua Tibia Wilderness AGTI CA 33.42 -116.99 BADL1 43.744 -101.941 Badlands NP BADL SD 43.81 -102.36 BALD1 34.058 -109.441 Mount Baldy Wilderness BALD AZ 33.95 -109.54 BAND1 35.780 -106.266 Bandelier NM BAND NM 35.79 -106.34 BIBE1 29.303 -103.178 Big Bend NP BIBE TX 29.33 -103.31Visibility Analysis: Details

April 2014 Abt Associates Inc. 332 BLIS1 38.976 -120.103 Desolation Wilderness DESO CA 38.9 -120.17 BLIS1 38.976 -120.103 Mokelumne Wilderness MOKE CA 38.57 -120.06 BOAP1 33.870 -106.852 Bosque del Apache BOAP NM 33.79 -106.85 BOWA1 47.947 -91.496 Boundary Waters Canoe Area BOWA MN 48.06 -91.43 BRCA1 37.618 -112.174 Bryce Canyon NP BRCA UT 37.57 -112.17 BRET1 29.119 -89.207 Breton BRET LA 29.87 -88.82 BRID1 42.975 -109.758 Bridger Wilderness BRID WY 42.99 -109.49 BRID1 42.975 -109.758 Fitzpatrick Wilderness FITZ WY 43.24 -109.6 BRIG1 39.465 -74.449 Brigantine BRIG NJ 39.49 -74.39 CABI1 47.955 -115.671 Cabinet Mountains Wilderness CABI MT 48.18 -115.68 CACR1 34.454 -94.143 Caney Creek Wilderness CACR AR 34.41 -94.08 CANY1 38.459 -109.821 Arches NP ARCH UT 38.73 -109.58 CANY1 38.459 -109.821 Canyonlands NP CANY UT 38.23 -109.91 CAPI1 38.302 -111.293 Capitol Reef NP CAPI UT 38.06 -111.15 CHAS1 28.748 -82.555 Chassahowitzka CHAS FL 28.69 -82.66 CHIR1 32.009 -109.389 Chiricahua NM CHIR AZ 32.01 -109.34 CHIR1 32.009 -109.389 Chiricahua Wilderness CHIW AZ 31.86 -109.28 CHIR1 32.009 -109.389 Galiuro Wilderness GALI AZ 32.6 -110.39 COHU1 34.785 -84.627 Cohutta Wilderness COHU GA 34.93 -84.57 CRLA1 42.896 -122.136 Crater Lake NP CRLA OR 42.92 -122.13 CRLA1 42.896 -122.136 Diamond Peak Wilderness DIPE OR 43.53 -122.1 CRLA1 42.896 -122.136 Gearhart Mountain Wilderness GEMO OR 42.51 -120.86 CRLA1 42.896 -122.136 Mountain Lakes Wilderness MOLA OR 42.33 -122.11 CRMO1 43.461 -113.555 Craters of the Moon NM CRMO ID 43.39 -113.54 

### Example 2 Assume you have chosen Use model grid cells at Class I area centroid . If you have set the Maximum Distance from Domainto 25 , and a Class I Area is more than 25 kilometers from the nearest model grid cell centroid, then a forecast is not generated for this particular Class I Area ( e.g. , Chiricahua, NM). As noted above, the CHIR1 monitor is linked to two other Class I Areas. If these two other areas are within 25 kilometers of a model grid cell centroid, then the monitor values from CHIR1 would be used in the forecast for these two areas (along with the model values associated with the centroid of each area). 

## 11.4 Final Check The Final Check window verifies the selections that you have made.Visibility Analysis: Details

April 2014 Abt Associates Inc. 333 

### Click the button Press here to verify your selections . If there are any errors, MATS will present a message letting you know. For example, if the path to a model file is invalid -- perhaps you misspelled the file name -- you would get the following error:

After making the necessary correction, click the button Press here to verify your selections

.Visibility Analysis: Details

April 2014 Abt Associates Inc. 334 

### When your window looks like the window above, click either Save Scenario & Runor Save Scenario. Save Scenario & Run will cause MATS to immediately run the scenario.


## 11.4.1 Running MATS in Batch Mode The Save Scenario button will save the scenario as a configuration file (.cfg file). The "*.cfg" file will be saved in the .\MATS\output directory. Several .cfg files can be created with the MATS interface and run later in batch mode. To do this, edit the default batch file located in the .\MATS directory. The file "batchmats.bat" should be edited with a text editor to point to the name and location of the .cfg files that will be run in batch mode.

After editing the batchmats.bat file, simply run the .bat file. MATS will start and run in the background.Output Navigator

April 2014 Abt Associates Inc. 335 

## 12 

# Output Navigator 12

The Output Navigatorallows you to load results files ( i.e. , *.ASR files ) that you have previously created in MATS. You can view these data in maps and in tables, or export the data to text files that you can then work with in a program such as Excel. To start, just click on the Output Navigatortab.

Click on the Loadbutton to view your file of interest. This will bring up the Open MATS Results filewindow. Choose a results file (with the .ASR extension) This will bring you back to the Output Navigator and display the available files.Output Navigator

April 2014 Abt Associates Inc. 336 

### The files listed fall into two categories: Configuration/Log Filesand Output Files . The Configuration Filestores the assumptions used in generating your results file. The Log Filestores information regarding the version of MATS used to create the results file and the date and time of its creation. To examine a file, right-click on the file that you want to view. For Output Files , this will give you three choices, Add to Map , View , and Extract
.Output Navigator

April 2014 Abt Associates Inc. 337 

### For the Configuration File and Log File you will see two options: Viewand Extract

.Output Navigator

April 2014 Abt Associates Inc. 338 

## 12.1 Add Output Files to Map
The Map Viewtab is initially empty, starting with just a blank map of the United States.

To map your results, click on the Output Navigatortab. Load the ASRfile that you want to view and then right-click on the particular Output Filethat you want to map. This will give you three choices, Add to Map , View , and Extract

. * Choose the Add To Mapoption.Output Navigator

April 2014 Abt Associates Inc. 339 

### This will bring you back to the Map Viewtab.

Details on how to generate a variety of maps are in the Map Viewchapter.Output Navigator

April 2014 Abt Associates Inc. 340 * Note that if you right-click on the Configuration Fileor Log Fileyou will only see two options: View and Extract . The Add To Map option is only relevant to the Output Files , as the Configuration and Log files do not have a geographic component. 

## 12.2 View Files To view a file of interest, right-click on it, and then choose View . There are three basic types of files available: Configuration , Log , and Outputfiles.



## 12.2.1 Configuration File A Configuration File stores the choices that you have made when using MATS. A useful feature of a Configuration File is that it is reusable. You can use an existing Configuration File, make some minor changes to generate a new set of results, without having to explicitly set each of the choices you made in the previous Configuration. To view a Configuration file from the Output Navigator , right-click on the file.Output Navigator

April 2014 Abt Associates Inc. 341 

### This will bring up the options that you chose when generating your results.Output Navigator

April 2014 Abt Associates Inc. 342 

## 12.2.2 Log File A Log File provides information on a variety of technical aspects regarding how a results file (*.ASR) was created. This includes the version of MATS, the date and time the *.ASR filewas created. To view a Log file from the Output Navigator , right-click on the file.

A separate Run Logtab will appear.Output Navigator

April 2014 Abt Associates Inc. 343 

### Click the Closebutton when you have finished viewing it. (The Run Log tab will disappear.)


## 12.2.3 Output Files An Output file is one of the file types within a *.ASR results file . The types of Output Files available depend on the type of analysis ( PM , Ozone , or Visibility ) and the output choices that you have specified in the Configuration File

. To view an Output file Output Navigator , right-click on a file.Output Navigator

April 2014 Abt Associates Inc. 344 

### This will bring up a Monitor Network Datatab. The upper left panel allows you to view the ID and latitude and longitude of the monitors in your data -- at the right of this panel there is a scrollbar with which you can locate any particular monitor of interest. The lower left panel allows you to view the other variables in the data.Output Navigator

April 2014 Abt Associates Inc. 345 

### The default option is to show all of the data in the lower left panel. If, however, you want to just view the data for a particular monitor -- in this example, monitor ID = "010331002" -- use the scrollbar (if needed) and then highlight this monitor. MATS will then display the values for this monitor in the bottom panel.Output Navigator

April 2014 Abt Associates Inc. 346 

### To view all of the data again, click on the Show Allbutton.

To eliminate missing values (denoted by negative numbers in the lower panel), check oneOutput Navigator

April 2014 Abt Associates Inc. 347 

### or more boxes in the panel in the upper right of the window. For example, to eliminate any monitors that do not have a ozone design value forecast, check the forecasted ozone design value variable " f_o3_dv ". MATS will automatically drop these values. (Note that the monitor that we previously highlighted [monitor ID = "010331002] has now dropped out of the display.)

If you want to save the data, you can click the Exportbutton and save the file. (It is unnecessary to add an extension. MATS automatically saves the file as a CSV text file and adds a ".csv" extension to your file name.) You can then view the file in Excel. 

## 12.3 Extract Files Extracting files allows you to export files from MATS and view them in another program. This is most relevant to the Output Files (as opposed to the Configuration/Log Files), which you may want to view and manipulate in a database program such as Excel. MATS will generate .CSVfiles. These are easily viewable in a number of programs. The simplest way to extract files is to check the box "Automatically Extract All Selected Output Files " on the initial window of the Configuration File(the same window where you give the Scenario Name ). Alternatively, you can use the Output Navigator .From Output Navigator load the results ( .ASR ) file of interest.Output Navigator

April 2014 Abt Associates Inc. 348 

### One quick method to extract all of the data in the results file is to click the Extract All button. An Extracting Allscreen will appear with a suggested name for the folder storing the results. MATS will use the Scenario Nameas the default folder name. If desired you can rename the folder to whatever you desire.

Click OK, and then MATS will export all of the files to this folder.Output Navigator

April 2014 Abt Associates Inc. 349 

### An alternative is to extract individual files. Right click on the file of interest, and choose the Extract option.

This will bring up the Extracting. Enter output file namewindow. By default, MATS will generate a folder with the Scenario Name(e.g., Example O3) and export a file with the same name used internally by MATS. You can change both the folder and the exported file name if desired.Map View

April 2014 Abt Associates Inc. 350 

## 13 

# Map View 13

The Map Viewtab allows you to further explore your results. Initially, it is empty, with just a blank map of the United States.

This section discusses how to:

· Loaddata onto the map;

· Choosing colors to represent the data (referred to as " plotting " in MATS);

· Zoomin and out on your map;

· Add and remove outlines for states, counties and Class 1 areas (these outlines are referred to as " Standard Layers ");

· Exportingmaps and CSV files;

· Removingdata from a map. 

## 13.1 Loading Variables There are two ways to bring data into a map. First, you may load data into a map with the Output Navigator . Alternatively, you can load data directly from the map view taskbar (see next sub-section ).Map View

April 2014 Abt Associates Inc. 351 

### To map your results, click on the Output Navigatortab. Load the ASRfile that you want to view and then right-click on the particular Output Filethat you want to map. Choose the Add to Mapoption.

This will bring you back to the Map Viewtab.Map View

April 2014 Abt Associates Inc. 352 

### Usually the next step is to plot your data. This is discussed next

. 

## 13.1.1 Loading with Taskbar You can load data for mapping directly from the MapViewtab, once you have exported your results file (as discussed in the Extract Filessub-section of the Output Navigator section). To start, click on the MapViewtab.Map View

April 2014 Abt Associates Inc. 353 

### Click on the Open a monitor network filebutton: This will bring you to the Open Monitor Networkwindow. Browse to the folder with the data file that you want to load.Map View

April 2014 Abt Associates Inc. 354 

### Click the Openbutton after selecting your file (or just double-click on the file you want to load) and this will take you to back to the Map Viewtab.Map View

April 2014 Abt Associates Inc. 355 

## 13.2 Plotting a Value To plot a value you must first load one or more variables into the MapView. Right click on the text in the left panel and choose Plot Value

.Map View

April 2014 Abt Associates Inc. 356 

### This will bring up the Shape Class Breakswindow.

Here you can choose the variable (or "Value") that you want to display and how it will be seen. Scroll through the drop-down Valuemenu and choose dv_best . This is forecasted visibility (measured in deciviews) on the days with the best visibility. (Note that a description of all results variables generated by MATS are described in the "Details" sections for Annual PM , Daily PM , Ozone , and Visibility .)Map View

April 2014 Abt Associates Inc. 357 

### There are a variety of display options that you can choose. These options are discussed in detail in the Plotting Optionssection. After choosing your display options, then click the Applybutton. View the map in the Map Viewtab. (You can move the Shape Class Breakswindow, if it is obscuring the map.) If you want to change your display options, go back to the Shape Class Breakswindow, make the changes, and click Apply again. You may do this as many times as needed. When you are satisfied with the map, click the Closebutton in the Shape Class Breaks window. This will bring you back to the Map Viewtab.Map View

April 2014 Abt Associates Inc. 358 

## 13.2.1 Plotting Options MATS gives you a number of plotting options with the Shape Class Breaks window. These are demonstrated with the results file "Tutorial Visibility - Forecasted Visibility - all design values.csv" generated after completing the visibility tutorial . The same concepts hold for other results files. With the Date drop-down menu you can specify a particular year (assuming the data have multiple years).Map View

April 2014 Abt Associates Inc. 359 

### With the Class Countoption, you can specify into how many groups you want to divide your data. The default is to use 5 bins. For most purposes this is a reasonable number.

If you choose Unique Valuesoption, you will have a separate bin or group for each unique value in your data. This can lead to hundreds of bins. Generally, this is not an option that you would want to choose. Note that if you choose this option, the Class Countand Marker Sizing(discussed next) will be inoperative.Map View

April 2014 Abt Associates Inc. 360 

### The Marker Sizingallows you to vary the size of the marker on your map based on the data values. The default is a Marker Sizingvalue of "0", which keeps the marker on your map all the same size. A value of "1" and higher gives the larger values progressively larger markers on the map.

The Start Coloroption allows you to set the color of the markers for the lowest values. The End Coloroption allows you to set the color of the markers for the highest values. MATS uses a mix of these two colors for intermediate values. The default colors are blue and yellow for the start and end. If you want to change the Start Color , click on the blue square. This will bring up the Colorwindow. The simplest option is to click on the color you prefer from the predefined Basic colorspanel (in the upper half of the Colorwindow), and then click OK

.Map View

April 2014 Abt Associates Inc. 361 

### (You can also double-click on desired color.)

If for some reason, you do not see the color you want to use in the Basic colorspanel, you can click the Define Custom Colorsbutton. Click in the large multi-color square to identify the color you want and then adjust the hue with the slider bar on the far right. You can save the color you generate by clicking the Add to Custom Colorsbutton.

When satisfied, click OK . This will bring you back to the Shape Class Breakswindow.Map View

April 2014 Abt Associates Inc. 362 

### You can change the End Color through a similar process. To test how your colors look, click the Applybutton. If you do not like what you see, click the Clear Breaksbutton. When you are finally satisfied with the look of your map, click the Closebutton. 

## 13.3 Zoom Options & Pan View
In addition to the plotting options available in the Shape Class Breaks window, there are various options on the task bar that you can choose to adjust the map. There are standard Zoom in and Zoom out options, as well as a Pan option that lets you manually move the map.
In addition, there is a Zoom to an areadrop-down menu . This lets you zoom to pre-specified regions, or "zoom frames", such as the continental US.Map View

April 2014 Abt Associates Inc. 363 

### If desired, you can change the "Zoom Frames" to whatever you are currently viewing. Choose Add Current View to List from the list of options in the drop-down menu.Map View

April 2014 Abt Associates Inc. 364 

### This will bring up the Add Framewindow. Type in whatever name you want to use for this "zoom frame" and this will be available whenever you use MATS.



## 13.4 Standard Layers
The Standard Layersdrop-down menu allows you to add and remove state, county, and Class 1 area borders. By default, MATS displays the state and county borders. These can often provide useful context to maps, however, at times they can obscure the markers somewhat -- this is most often a problem with the county boundaries. To eliminate a layer, open the Standard Layersdrop-down menu and click on the active layer that you want to remove. This will bring up a map view with the layer removed.

To add a layer back, choose the layer you want to add from the Standard Layersdropdown menu.Map View

April 2014 Abt Associates Inc. 365 

## 13.5 Exporting Maps & Data Files MATS allows you to export maps and data from the Map Viewtab. To export a BMP file , click on the Export current map view to an image fileoption . (The next subsectiondiscusses exporting the underlying data.)

This will up a window where you can name your image. Browse to whatever folder in which you want to store your image.Map View

April 2014 Abt Associates Inc. 366 

### Your .BMP filecan be easily viewed in a variety of software applications. Note however, that this is just an image, and you will not be able to work with it in a GIS program the way you might work with a .SHP file.Map View

April 2014 Abt Associates Inc. 367 

## 13.5.1 Exporting CSV Data File If desired, you can export a CSV filewith the data used to generate your map. Just right click on variable of interest in the left panel, and choose the Export as CSV Fileoption.Map View

April 2014 Abt Associates Inc. 368 

### Note that this exports the same data that the Output Navigatorwould export. Choose whichever approach is easier.Frequently Asked Questions

April 2014 Abt Associates Inc. 369 

## 14 

# Frequently Asked Questions 14
This section answers questions that have arisen when running MATS. 

## 14.1 Where is there a description of output variables? Descriptions of the output variables are in the separate "Details" sections for Annual PM , Daily PM , Ozone , and Visibility

. 

## 14.2 Removing Data You can have multiple data files in a map. If you decide to remove a datafile, right click on the variable that you want choose the Removeoption.

This will bring back the map without the undesired data.Frequently Asked Questions

April 2014 Abt Associates Inc. 370References

April 2014 Abt Associates Inc. 371 

## 15 

# References 15
Chow, J.C., J.G. Watson, L.W.A. Chen, W.P. Arnott, and H. Hoosmuller (2004). "Equivalence of Elemental Carbon by Thermal/Optical Reflectance and Transmittance with Different Temperature Protocols", Environmental Science and Technology, 38(16): 4414-4422. Clegg, S.L., P. Brimblecombe, and A.S. Wexler (1998). "Aerosol Inorganics Model: A Thermodynamic Model of the System H + 

### -NH4 + 

### -SO4 2- 

### -NO3

- 

### -H2O) at Tropospheric Temperatures." J. Phys. Chem. 102A: 2137:2154. Frank, Neil (2006). “Retained Nitrate, Hydrated Sulfates, and Carbonaceous Mass in Federal Reference Method Fine Particulate Matter for Six Eastern U.S. Cities” JAWMA. Vol 56: 500-511. IMPROVE (2006). “ Revised IMPROVE Algorithm for Estimating Light Extinction from Particle Speciation Data” , January 2006, http://vista.cira.colostate.edu/improve/Publications/GrayLit/gray_literature.htm. Turpin, B.J. and H-J Lim (2001). "Species Contributions to PM2.5 Mass Concentrations: Revisiting Common Assumptions for Estimating Organic Mass", Aerosol Science and Technology, 35: 602-610. U.S. EPA (2003). "Federal Reference Method Quality Assurance Report." U.S. EPA (2006). "Procedures for Estimating Future PM2.5 Values for the PM NAAQS Final Rule by Application of the Speciated Modeled Attainment Test (SMAT)" http://www.epa.gov/scram001/guidance_sip.htm

. U.S. EPA (2007). "Guidance on the Use of Models and Other Analyses for Demonstrating Attainment of Air Quality Goals for Ozone, PM2.5 and Regional Haze", April 2007. EPA-454/B-07-002, http://www.epa.gov/scram001/guidance_sip.htm

.