11/27/2007 

A Modeling Protocol for the OTC SIP Quality 

Modeling System For Assessment of the Ozone 

 National Ambient Air Quality Standard 

in the Ozone Transport Region 

The Modeling Committee of the 

Ozone Transport Commission
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TABLE OF CONTENTS 

1 STUDY DESIGN 

1.1 Background 

1.2 Objectives 

1.3 Photochemical Modeling System 

1.4 Deliverables 

1.5 Schedule 

2 MANAGEMENT STRUCTURE 

2.1 OTR Oversight Committee 

2.2 OTR Photochemical Modeling Workgroup 

2.3 OTR Meteorological Modeling Workgroup 

2.4 OTR Emission Inventory Development Workgroup 

2.5 OTR Control Strategy Development Workgroup 

2.6 OTC Modeling Committee 

 

3 OTR MODELING DOMAIN 

3.1 Description 

3.2 Horizontal Grid Size 

 

3.2 Number of Vertical Layers 

 

4 OZONE EPISODES 

4.1 EPA Episode Selection Criteria 

4.2 Proposed Episode Selection Procedure 

 
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5 METEOROLOGICAL FIELDS

5.1 MM5 Meteorological Fields 

5.2 Quality Assurance of MM5 Meteorological Fields 

6 BASE CASE EMISSION INVENTORIES FOR 2002 

6.1 2002 Emission Inventories for OTC States 

 

6.2 2002 Emission Inventories for All Other OTR States 

 

7 BASE CASE EMISSION INPUT FILES FOR 2002 

7.1 Preparation of 2002 Emission Input Files for the OTR Domain 

7.2 Quality Assurance of 2002 Emission Input Files for the OTR Domain 

 

8 AIR QUALITY DATA 

8.1 Initial conditions 

8.2 Boundary conditions 

 

8.3 Ambient Air Quality Data 

9 DIAGNOSTIC ANALYSES 

9.1 Quality Assurance Tests of Input Components 

 

9.2 Diagnostic Tests 

 

 

10 MODEL PERFORMANCE EVALUATION 

10.1 Performance Criteria 

10.2 Statistical Performance Measures 
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11 CAA EMISSION INVENTORIES FOR 2010 AND 2013 

11.1 CAA Emission Inventories for OTC States for 2010 

11.2 CAA Emission Inventories for all other OTR States for 2010 

11.3 CAA Emission Inventories for OTC States for 2013 

11.4 CAA Emission Inventories for all other OTR States for 2013 

12 CAA EMISSION INPUT FILES FOR 2010 AND 2013 FOR THE OTR DOMAIN 

12.1 2010 CAA Emission Input Files for OTR Domain 

12.2 2013 CAA Emission Input Files for OTR Domain 

13 OZONE CONTROL STRATEGY FOR THE OTR DOMAIN 

13.1 OTC CALGRID System Screening Runs 

13.2 OTC SIP Modeling Platform Runs 

13.3 Analysis of Available Air Quality and Emission Databases 

13.4 OTR Domain Ozone Control Strategy 

14 OZONE CONTROL STRATEGY EMISSION INPUT FILES 

14.1 2010 Ozone Control Strategy Emission Input Files for OTR Domain 

14.2 2013 Ozone Control Strategy Emission Input Files for OTR Domain

 

15 OZONE PREDICTIONS FOR 2010 and 2013 

15.1 Initial Conditions 

15.2 Boundary conditions 

15.3 CAA Ozone Predictions for 2010 and 2013 

15.4 Ozone Control Strategy Predictions for 2010 and 2013 
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16 DOCUMENTATION REPORT 

17 REFERENCES 

APPENDIX A: Work Plan for the Development and Application of the OTC SIP Quality 

 Modeling System For Assessment of the Ozone National Ambient Air 

 Quality Standard in the Ozone Transport Region 

APPENDIX B: Workgroups for the Development and Application of the OTC SIP Quality 

 Modeling System For Assessment of the Ozone National Ambient Air 

 Quality Standard in the Ozone Transport Region 

APPENDIX C: MOU for the Development and Application of the OTC SIP Quality 

 Modeling System For Assessment of the Ozone National Ambient Air 

 Quality Standard in the Ozone Transport Region 
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1 STUDY DESIGN 

1.1 Background 

Moderate and serious non-attainment areas in the Ozone Transport Region (OTR) are required 

to attain the 8-hour ozone NAAQS by 2010 and 2013, respectively. The Ozone Transport 

Commission (OTC) has embarked on the task of preparing an SIP ozone modeling system for 

exercising photochemical grid model(s) to assess the impact of candidate ozone control 

strategies in moderate and serious non-attainment areas in the OTR. The OTC Directors 

endorsed the Modeling Protocol for the OTC SIP Quality Modeling System For Assessment of 

the Ozone National Ambient Air Quality Standard in the Ozone Transport Region at the 

November 12-13, 2003 Fall meeting of the OTC. 

This modeling protocol outlines procedures to prepare and use the OTC SIP ozone modeling 

system to help design an ozone attainment strategy to attain the ozone 8-hour NAAQS in the 

OTR. Emission inventories for point, area, on–road and off-road sources of NOx, VOC and CO 

will be developed for a base year of 2002. BEIS3 will be used to estimate biogenic emissions. 

MM5 will be used at a 12 km grid resolution and, in the photochemical grid model, 4 km grid 

cells will be nested in urban areas where appropriate. A model performance evaluation will be 

prepared for 2002. If model performance is satisfactory, emission input files reflecting candidate 

control strategy scenarios for 2010 and 2013 will be prepared, and 2010 and 2013 ozone levels 

will be simulated with the modeling system. OTC States with moderate and serious nonattainment areas will then use these modeling results to help support required ozone attainment 

demonstrations. 

1.2 Objective 

The New York Department of Environmental Conservation has agreed to be the lead agency 

for developing a SIP quality ozone modeling system for assessing the future year attainment 

of the ozone 8-hour NAAQS in the OTR. The CMAQ or CAMx model will be used to evaluate 

the effectiveness of control strategies in the OTR Modeling Domain. The regulatory objective will 

be to design an ozone control strategy that will result in attainment of the 8-hour ozone NAAQS 

in moderate non-attainment areas by 2010, and in serious non-attainment areas by 2013. 

1.3 Photochemical modeling System 

Currently there is no guideline modeling system for demonstrating ozone attainment. The OTC 

Modeling Committee in its prior work exercised both CMAQ and CAMx and noticed that even 

though these models had performed similarly in estimating ozone on an over-all basis, the level 

of agreement between the simulated and measured concentrations varied from good to bad 
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depending on the model and depending upon the simulation day. So, as part of this protocol, 

both models (which continue to be updated by their developers) will be applied for an episode 

that occurred in 2002. Based upon the performance, one of these models would be selected for 

further application and use to evaluate the effectiveness of proposed control strategies in the 

OTR. The analysis identifying the basis for the selection of the modeling system will be 

communicated through the OTC modeling committee. 

The OTC Modeling Committee also examined two emissions processors (EMS2001 and 

SMOKE, both using CB4 chemistry ) in its prior work and concluded that there are differences 

between them that could be minimized by forcing the models to use a common speciation and 

surrogate data base. In the current protocol, we envision the use of both of them in the initial 

assessment for an episode in 2002 and then, based upon the best performance, one of these 

emission processors would be selected for constructing emission files for the SIP quality ozone 

modeling system for the OTR Domain. 

1.4 Deliverables 

The key deliverables for the SIP quality ozone modeling system for the OTR are listed below. 

• Select Ozone Episodes 

• Prepare Meteorological Fields 

• Prepare 2002 Emission Inventories for each OTC State 

• Acquire 2002 Emission Inventories for non-OTC States in the OTR Domain 

• Prepare 2002 Emission Input Files for the OTR Domain 

• Complete 2002 Model Performance Evaluation for the OTR Domain 

• Prepare 2010 and 2013 CAA Emission Inventories for each OTC State 

• Acquire 2013 Emission Inventories for non-OTC States in the OTR Domain 

• Prepare 2010 and 2013 CAA Emission Input Files for the OTR Domain 

• Complete Modeling Runs for 2010 and 2013 CAA Scenarios 

• Design Control Strategy for the OTR Modeling Domain. 

• Prepare 2010 and 2013 Emission Input Files for OTR Control Strategy 

• Complete Modeling Runs for 2010 and 2013 for Control Strategy 

• Complete Evaluation Report for 2010 and 2013 Control Strategy 

 

1.5 Schedule 

The schedule for developing the SIP quality modeling system and the assessment of the ozone 

NAAQS in the Ozone Transport region is provided in Appendix A. 

2 MANAGEMENT STRUCTURE 

 

2.1 OTR Oversight Committee 

OTC Air Directors will serve as the OTR Oversight Committee. The Directors will ensure that 
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2002, 2010 and 2013 CAA emission inventories are prepared for each OTC state in the OTR 

domain, and will also be responsible for obtaining emission inventories for OTR states that are 

not members of the OTC. The Directors will oversee the design of ozone control strategies for 

the OTR, and will make the final decision on any funding needed to develop the OTC SIP quality 

modeling system. The Directors will review all OTC SIP quality modeling system documentation 

before it is released to interested parties. 

2.2 OTC Modeling Committee 

The state members of the OTC Modeling Committee will provide policy and day to day 

technical guidance for the development of the OTC SIP quality modeling system The 

Committee will recommend (to the OTC Air Directors) what tasks need to be funded in order to 

develop the OTC SIP quality modeling system in a timely fashion. 

2.3 OTR Photochemical Modeling Workgroup 

 

The OTR Photochemical Modeling Workgroup will be responsible for preparing the modeling 

assessment of the ozone NAAQS in the OTR. The Workgroup will be responsible for collecting 

and processing model input data, setting up all model input files, performing model runs, and 

interpreting and documenting the results of the modeling analyses for the OTR domain. 

The Workgroup will prepare and submit all OTC SIP quality modeling system documentation to 

the OTC Air Directors. Gopal Sistla, NY DEC will serve as the lead for this group. 

2.4 OTR Meteorological Modeling Workgroup 

 

The OTR Meteorological Modeling Workgroup will be responsible for preparing and assessing 

MM5 meteorological fields for the OTR domain. The OTR Meteorological Modeling Workgroup 

will work with the OTR Photochemical Modeling Workgroup to prepare all meteorological input 

files for the OTC SIP quality modeling system. Mike Woodman, MDE, will serve as the lead for 

this group. 

2.5 OTR Emission Inventory Development Workgroup 

The OTR Emission Inventory Development Workgroup will be responsible for obtaining or 

developing guidance for preparing 2002, 2010 and 2013 state emission inventories for all states 

in the OTR. Ray Malenfant, DE DNREC, will serve as the lead for this group. 

2.6 OTR Control Strategy Development Workgroup 

The OTR Control Strategy Development Workgroup will be responsible for designing an ozone 

control strategy for the OTR Domain that will attain the ozone NAAQS by 2010 in moderate nonattainment areas and 2013 in serious non-attainment areas. The Workgroup will work with OTR 

states and the OTC stationary and mobile source committees to design an effective ozone 

control strategy for the OTR domain. Jeff Underhill, NH DES, will serve as the lead for this 

group. 
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3 OTR MODELING DOMAIN 

3.1 Description 

The modeling domain selected (see Figure 1 (where?)) follows the national grid adopted by the 

Regional Planning Organizations (RPOs), but with focus on the eastern U.S. The areal extent of 

the domain was selected such that the northeastern areas of Maine are well inside the domain. 

Based upon the existing computer resources, the southern and western boundaries were limited 

to the region shown in Figure 1. At a horizontal grid resolution of 12 km, it is estimated that 

there are 160 grids in the east-west and 150 grids in north-south direction. Depending upon the 

need and available resources, a 4 km grid over the selected urban areas could also be 

considered in this exercise. 

3.2 Horizontal Grid Size 

Following EPA and as noted above, a 12 km grid resolution will be used for most of the domain, 

with 4 km grid cells nested in urban areas where appropriate. This is a compromise between a 

finer grid mesh, which would offer greater resolution but at higher computational costs. A

coarser mesh may not be appropriate for urban area applications. 

3.3 Number of Vertical Layers 

Similar to the horizontal grid spacing which is fixed by the default set forth in the design of the 

meteorological model, in this case 12 km, the definition of the vertical structure could also be 

adopted one-to-one of the meteorological model. However, based upon prior experience, the 

vertical extent of the model was set around a height of 6 to 8 km. Also, as the number of levels 

in the vertical increases, so does the computational time as well as the storage requirements for 

the data. On the other hand, limiting the vertical resolution to a few layers would inherently 

discard the detailed information provided by the meteorological model. Thus a compromise 

solution would be to maintain the high resolution with a one-to-one design of the vertical layers 

up to approximately 1 or 2 km yielding around 7 to 10 levels, followed by a collapse of the MM5 

upper layers to around 6 to 8 km to form another 6 to 8 levels. Thus, under this scenario there 

would be a total of 13 to 18 layers in the vertical with 7 to 10 levels below 2 km and the 

remaining between 2 and 8 km. It should be noted that the mid-point of layer 1 in this analysis 

is around 10 m. 

 

4 OZONE EPISODES 

4.1 Episode Selection Criteria 

Since it would be impractical to model every violation day, EPA has recommended targeting a 

select group of episode days for ozone attainment demonstrations. Such episode days should 

be (1) meteorologically representative of typical high ozone exceedance days in the domain, 
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and (2) so severe that any control strategies predicted to attain the ozone NAAQS for that 

episode day would also result in attainment for all other exceedance days. 

4.2 Proposed Episode Selection Procedure 

While the above suggested approach is perhaps feasible for isolated urban areas, such an 

approach may not be meaningful given the areal extent of concern and the modeling domain. 

Also, selection of episodes from different years would require the generation of the 

meteorological fields and emissions database, which would be an extremely difficult proposition 

given the modeling domain. A major portion of the ozone season of 2002 will be simulated with 

the OTC SIP modeling system. The 2002 ozone season had significant number of high 

exceedance days (the spatial distribution of the daily 1-hr and 8-hr maxima over the eastern U. 

S. can be examined at the site ftp://www.dec.state.ny.us/dar/air_research/htdocs/index.html). 

It is anticipated that the total number of days examined under this approach would far exceed 

the recommended two or three episodes, and would also provide for better assessment of the 

simulated pollutant fields. EPA has also recommended using 2002 as the base year for the SIP 

emission inventory. 

5 METEOROLOGICAL FIELDS 

5.1 MM5 Meteorological Fields 

The MM5 setup has been described by Zhang (2000) for generating meteorological fields that 

are to be based on modified Blackadar scheme for the boundary layer. Since there are a variety 

of options that can be exercised in the application of MM5, initial testing will be performed for a 

high ozone event of 2002 with the most commonly used default options as well as with modified 

boundary layer schemes. It is anticipated that these MM5 simulations will be able to define the 

set of options which will be used to develop the remainder of the simulation period. Details of 

these experiments and results will be posted on the web site as well as will be presented at the 

appropriate venues. 

5.2 Quality Assurance of Meteorological Fields 

As a part of this effort, the simulated meteorological fields will be compared to data collected 

under CASTNET. Prior experience has shown that this approach provides for an independent 

assessment of the simulated meteorological conditions. Also, data from any other special 

measurements will be sought and compared. This analysis should provide a degree of 

confidence in the simulated meteorological fields and their use in photochemical grid modeling. 

This work will be coordinated through the meteorological model work group. 

6 BASE CASE EMISSION INVENTORIES FOR 2002 
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6.1 2002 Base Case Emission Inventories for OTC states 

Each state in the OTR Domain will prepare a 2002 base year Emission Inventory that include 

VOC, NOx, and CO for a typical ozone summer day. States are to follow EPA guidance 

documents for this base year inventory which is due to EPA by June 1, 2004. Note this 

inventory may also be qualified as the consolidated emissions regulatory report (CERR). 

All emission categories will be estimated for each county and state and the seasonal factors will 

facilitate spatial and temporal adjustments for modeling. Point and area source data will be 

submitted by individual states to EPA for uploading to EPA's National Emission Inventory (NEI) 

database using the required EPA format. MOBILE6.2 input files and VMT data will be submitted 

to NEI so that EPA can generate on-road mobile emissions for each state by county in a format 

that can be easily gridded and speciated. Similarly, off-road input files will be sent to EPA for 

running the latest NONROAD model. Biogenic emissions will be estimated with EPA’s BEIS-3 

emissions model. 

It is anticipated that these inventories developed by the states will follow the EPA prescribed 

approach and should be formatted in a consistent manner. While this protocol is to deal with the 

8-hr ozone issues, the inventory would also contain the necessary information for exercising the 

particulate option of the photochemical model. This would be of help in those cases where the 

one-atmosphere option is to be exercised in the assessment. Biogenic emissions will be 

estimated with EPA’s BEIS-3 emissions model 

6.1 2002 Base Case Emission Inventories for All Other States in the OTR 

A 2002 base year emission inventory that include VOC, NOx, and CO for a typical ozone 

summer day will be obtained for all non-OTC states in the OTR. It is anticipated that these 

inventories will be developed following EPA guidance, and will be formatted in a consistent 

manner. 

 

7 BASE CASE EMISSION INPUT FILES FOR 2002 

7.1 Preparation of 2002 Emission Input Files for the OTR Domain 

Emissions data will be processed using EMS95/EMS2000, and SMOKE. The surrogate data 

files for the OTR grid have been previously developed by NY DEC and will be used in this study. 

For those pollutants that depend upon ambient temperature, MM5 layer-1 gridded temperature 

fields will be used. 

7.2 Quality Assurance of 2002 Emission Input Files for the OTR Domain 

The processing of the emissions data will be accompanied with several quality checks before 

the data are exercised in the simulations. Prior experiences have shown that considerable time 

and resources are often invested in developing the gridded emissions data. While there are 

many avenues to improve or correct the data, based upon consensus of the OTC 
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Photochemical Modeling Workgroup, a definite closure of the emissions processing will be 

adhered to and any further changes or corrections will be archived and incorporated at a later 

date. In performing this work close attention will be paid to the emissions within the OTR and, if 

necessary, corrections will be incorporated on the advice of the OTC Photochemical Modeling 

Workgroup

Hourly plume heights will be calculated and emissions from sources with plume heights below 

the top of the first layer will be assigned to the appropriate 5 by 5 kilometer surface grid cell. 

Emissions from sources with plume heights above the top of the first layer will be assigned to 

the appropriate grid cell in the second layer. 

 

Biogenic emissions will be prepared for each episode day using BEIS-3. The temperature data 

from MM5 layer-1 will be used along with cloud cover information obtained from MM5. 

8 AIR QUALITY DATA 

7.1 Initial conditions 

Prior experiences have shown that a 3-day ramp-up period is sufficient to establish pollutant 

levels that are encountered in the beginning of the ozone episode. The initial conditions at the 

startup would be for “clean” conditions. 

7.2 Boundary conditions 

In prior studies attempts have been made to include any information that is available from 

ozonesonde and from monitors that are near the western and northern boundaries of the 

modeling domain. For this study, similar attempts will be made to obtain pollutant data at the 

boundaries. In the absence of reliable boundary condition data, “clean “ conditions will be 

assumed for boundary conditions. 

 

7.3 Ambient Air Quality Data 

Ambient air quality data will be extracted from the EPA AQS archive for ozone, CO, NOx, and 

total and speciated hydrocarbons reported as part of the PAMS network. Also, data from 

CASTNET will be obtained. Since the OTR modeling domain extends over two time zones, 

while the model simulations are reflective of a single time zone, EST, there will be a need to 

”correct” the clock and assemble the ambient air quality database. Any special measurements 

that are relevant to this study during the summer of 2002 will also be acquired, including upper 

air measurements. 

9 DIAGNOSTIC ANALYSES 

9.1 Quality Assurance Tests of Input Components 

 
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Before proceeding with modeling, all air quality, emissions, and meteorological data will 

be reviewed to ensure completeness, accuracy, and consistency. Any errors, missing 

data or inconsistencies, will be addressed using appropriate methods that are consistent with 

standard practices. 

9.2 Diagnostic Tests 

 

Attempts will be made to do diagnostic testing, to ensure that the simulated ozone patterns are 

in agreement with the measurements over the entire simulation period. While it is unrealistic to 

expect day-to-day agreement between the measured and predicted data, close attention will be 

paid to the changes in pattern of the measured ozone levels and the ability of the model to 

capture such changes. 

10 MODEL PERFORMANCE EVALUATION 

10.1 Performance Criteria 

This is an area that will likely require substantial dialog among member states. While there are 

many statistical tests that can be applied, it is important to define a priori some of the conditions 

of the analysis and the targets of evaluation. Also, it is quite critical to define the areal extent for 

which the assessment needs to be done to address the performance of the model. A 

"strawman" outlining the procedures will be developed for the model performance evaluation. 

The strawman could have 3 or 4 levels of tests covering all or portions of the domain using daily 

maximum, daily average, daytime average, 8-hour maxima, and other combinations of ozone 

concentrations to assess the model performance. Similarly, the statistical tests are to be 

applied to the precursor data as well, recognizing that all tests applied to the ozone data may or 

may not be valid. Thus, it is suggested that the statistical tests be geared appropriately based 

on the quality and quantity of the database. 

As part of the model assessment, qualitative analysis will also be performed by comparing 

predicted and measured pollutant fields to establish if the spatial patterns are captured by the 

modeling system. This is a critical step, since the measured concentrations may fall into a 

neighboring grid cell (but not at the measured location itself) and may be found to be in good 

agreement. 

Another area that is quite important is the predictive ability of the model with respect to height. 

Recognizing that the pollutants trapped above the mixed layer during the overnight hours would 

mix down during the daytime, comparison will be made between measurements and model 

predictions. Also, as noted in the work plan, special attention will be paid to elevated 

monitoring stations, such as the television tower near Durham, North Carolina; and the Sears 

Tower in Chicago, Illinois, and any other special monitors. 
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10.2 Statistical Performance Measures 

The recommended EPA procedures will be used to calculate the recommended performance 

measures. At a minimum, the following three statistical performance measures will be used to 

assess CAMx model performance for each episode. 

• Unpaired highest-prediction accuracy 

 This measure quantifies the difference between the highest observed eight hour 

 value in the domain and the highest predicted value in the domain. The acceptable 

 performance range is plus or minus 15-20 percent. 

 

• Normalized bias 

 This measure indicates the degree to which simulated eight hour values are over or 

 under-predicted. The acceptable performance range is plus or minus 5-15 percent. 

 

• Gross error of all pairs above 40 ppb 

 This measure indicates the average discrepancy between predicted and observed 

 values and provides an overall assessment of model performance. The 

 acceptable performance range is 30-35 percent. 

11 CAA EMISSION INVENTORIES FOR 2010 AND 2013 

11.1 CAA Emission Inventories for OTC States for 2010 

Each OTC state in the OTR Domain will prepare a 2010 CAA emission inventory that is 

consistent with the regulations and rules adopted or expected to be in-place. The inventory will 

be developed consistent with EPA guidance. The states will develop the information on growth 

factors and controls used in the development of the inventory. Each state will submit a report on 

the development of these future year inventories. 

Since the electric energy generation and use are highly inter-connected, coupled with the 

existing rules on trading and banking of pollutants, it is expected that an inventory consistent 

with this information would be developed for all electric energy generation units using models

such as IPM.

Recognizing that any prediction of future emissions are subject to changes, the OTC Modeling 

Committee would develop a decision framework on obtaining these emissions to be consistent 

with the OTC SIP quality modeling system schedule (Appendix A). 

11.2 CAA Emission Inventories for all other OTR States for 2010 
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A 2010 CAA emission inventory that includes VOC, NOx, and CO for a typical ozone summer 

day will be obtained for all non-OTC states in the OTR. It is anticipated that these inventories 

will be developed following EPA guidance, and will be formatted in a consistent manner 

11.3 CAA Emission Inventories for OTC States for 2013 

Each OTC state in the OTR Domain will prepare a 2013 CAA emission inventory that is 

consistent with the regulations and rules adopted or expected to be in-place. The inventory will 

be developed consistent with EPA guidance. The states will develop the information on growth 

factors and controls used in the development of the inventory. Each state will submit a report on 

the development of these future year inventories. 

Since the electric energy generation and use are highly inter-connected, coupled with the 

existing rules on trading and banking of pollutants, it is expected that an inventory consistent 

with this information will be developed for all electric energy generation units using models such 

as IPM. 

11.4 CAA Emission Inventories for All Other states for 2013 

A 2013 CAA emission inventory that includes VOC, NOx, and CO for a typical ozone summer 

day will be obtained for all non-OTC states in the OTR. It is anticipated that these inventories 

will be developed following EPA guidance, and will be formatted in a consistent manner 

12 CAA EMISSION INPUT FILES FOR 2010 AND 2013 FOR THE OTR DOMAIN 

12.1 CAA Emission Input Files for OTR Domain for 2010 

2010 CAA emissions data will be processed using EMS2001 and/or SMOKE. For those 

pollutants that depend upon ambient temperature, MM5 layer-1 gridded temperature fields will 

be used to estimate hourly emission rates. The biogenic emission input files prepared for the 

base 2002 will be used as a surrogate for 2010 biogenic emissions. The processing of the 

emissions data will be accompanied with the quality assurance checks previously described in 

section 7.2 Quality Assurance of 2002 Emission Input Files for the OTR Domain. 

12.2 CAA Emission Input Files for OTR Domain for 2013 

2013 CAA emissions data will be processed using EMS2001 and/or SMOKE. For those 

pollutants that depend upon ambient temperature, MM5 layer-1 gridded temperature fields will 

be used to estimate hourly emission rates. The biogenic emission input files prepared for the 

base 2002 will be used as a surrogate for 2013 biogenic emissions. The processing of the 

emissions data will be accompanied with the quality assurance checks previously described in 

Section 7.2 Quality Assurance of 2002 Emission Input Files for the OTR Domain. 
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13 OTR DOMAIN OZONE CONTROL STRATEGY 

13.1 OTC CALGRID System Screening Runs 

A series of CALGRID screening runs will be performed to investigate the level of emissions 

reductions needed both within and outside of the OTR. This will help to identify potential 

emission reductions scenarios that can be used to lower ozone levels in the OTR. 

13.2 OTC SIP Modeling Platform Runs 

OTC SIP modeling platform CAA runs for 2010 and 2013 will be reviewed to help determine the 

level of emissions reductions needed to attain the ozone NAAQS. VOC and NOX sensitivity 

runs will also be performed to help identify potential emission reductions scenarios that can be 

used to lower ozone levels in the OTR. 

13.3 Analysis of Available Air Quality and Emission Databases 

A review of air quality and emission databases (for example, EPA Clear Skies and Transport 

Rule emission files) will be performed to help identify potential source sectors of ozone 

precursors. Analysis of available EPA modeling results will also be performed to help identify 

potential source sectors of ozone precursors in, and upwind, of the OTR domain. 

13.4 Ozone Control Strategy for the OTR Domain 

The OTR Control Strategy Development Team will review CALGRID results, other available 

databases, and EPA databases, to help identify potential control programs. The Team will work 

with OTR states and the OTC stationary, area and mobile source committees to design ozone 

control strategies for the OTR Domain with the goal of meeting regulatory target dates. 

14 OZONE CONTROL STRATEGY EMISSION INPUT FILES 

14.1 Ozone Control Strategy Emission Input Files for the OTR Domain for 2010 

Emissions files for the selected ozone control strategy for the OTR Domain for 2010 will be 

prepared in a consistent manner as per schedule. If necessary, additional IPM simulations may 

be performed to obtain EGU emission estimates. 

14.2 Ozone Control Strategy Emission Input Files for the OTR Domain for 2013 
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Emissions files for the selected ozone control strategy for the OTR Domain for 2013 will

prepared in a consistent manner as per schedule. If necessary, additional IPM simulations may 

be performed to obtain EGU emission estimates. 

 

15 OZONE PREDICTIONS FOR ATTAINMENT IN 2010 and 2013 

15.1 Initial Conditions 

The initial conditions at the startup will be for “clean” conditions. The OTR Modeling Team will 

use the 2002 initial condition files as a surrogate for initial conditions in 2010. 

15.2 Boundary conditions 

EPA will be consulted for guidance in estimating boundary conditions for 2010 and 2013 or 

under default would utilize those adapted for the Base 2002 base year simulation. 

15.3 CAA Ozone Predictions for 2010 and 2013 

The model will be run with the CAA emission files developed for 2010 and 2013. Tile plots, 

difference plots and model statistics will be prepared to help characterize the extent of 

any remaining non-attainment areas predicted in the OTR in 2010 and 2013. 

15.4 Ozone Control Strategy Ozone Predictions for 2010 and 2013 

The model will be run with OTR control strategy emission files prepared for 2010 and 2013. Tile 

plots, difference plots and model statistics will be prepared to help characterize the extent of any 

remaining non-attainment areas predicted in the OTR for the year 2010 and 2013. 

16 DOCUMENTATION 

A report titled “Assessment of the Ozone National Ambient Air Quality Standards in the Ozone 

Transport Region will be prepared by the OTR Modeling Team. The report would cover model 

performance evaluation, and an evaluation of the OTR control strategy runs for 2010 and 2013. 

This technical document will be made available to all interested parties and will be used by the 

member States in their SIP submission documentation as needed. 

17 REFERENCES 

Wick Havens (2000): Development of an Emissions Inventory for Regional/Urban-scale 

Modeling, MARAMA-RTC (see http://www.marama.org/). 

Gopal Sistla (1999): Development of a surrogate database for use in Regional/Urban-scale 
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Modeling at 4 km spatial resolution (see http://envpro.ncsc.org/emcenter/). 

Dalin Zhang (2000): Development of meteorological database for summer 1997 using MM5 at 

12 km resolution in Photochemical Model Simulations.