773 San Marin Drive, Suite 2115, Novato, CA 94998 415.899.0700 Draft Report

Evaluation of Preliminary MM5 Meteorological Model Simulation for the June-July 2006 Denver Ozone SIP Modeling Period Focused on Colorado

Prepared for:

Regional Air Quality Council 1445 Market Street, Suite 260 Denver, Colorado 80202

Prepared by:

Dennis McNally George Schewe Alpine Geophysics, LLC 7341 Poppy Way Arvada, Colorado 80007

Jeremiah Johnson Ralph Morris ENVIRON International Corporation 773 San Marin Dr. Suite 2115 Novato, CA 94998

February 25, 2008F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc i TABLE OF CONTENTS

1 INTRODUCTION................................................................................................................ 1 -1

2 METHODOLOGY .............................................................................................................. 2-1 2.1 Model Selection and Application..................................................................................... 2-1 2.2 Evaluation Approach ....................................................................................................... 2 -2

3 MM5 PERFORMANCE EVALUATION RESULTS ...................................................... 3-1 3.1 Quantitative Model Evaluation Results ........................................................................... 3-1 3.1.1 Temperature Bias and Error................................................................................. 3-2 3.1.2 Mixing Ratio Bias and Error................................................................................ 3-3 3.1.3 Wind Index of Agreement ................................................................................... 3-4 3.1.4 Spatial Mean Temperature and Mixing Ratio...................................................... 3-5 3.1.5 Spatial and Temporal Mean Wind Speed Index of Agreement, Wind Speed and Wind Direction ......................................................................... 3-5 3.2 Qualitative Monthly Prec ipitation Analysis .................................................................... 3-7

4 UPPER-AIR METEOROL OGICAL ANALYSIS............................................................ 4-1

5 COMPARISON WITH OTHER MM5 SIMULATIONS................................................ 5-1 5.1 Comparison to Other 4 Km Simulations.......................................................................... 5-1

6 REFERENCES................................................................................................................... .. 6-1

TABLES

Table 2-1. MM5 Vertical Domain Specification................................................................... 2-3 Table 3-1. Temperature Bias (K) for June and July 2006 MM5 by Month and by State and Region in the 36 km Domain........................................ 3-8 Table 3-2. Temperature Bias (K) for June and July 2006 MM5 by Month and by State in the 12 km Domain. .......................................................... 3-9 Table 3-3. Temperature Bias (K) for June and July 2006 MM5 in the 4 km Doma in........................................................................................................... 3-9 Table 3-4. Temperature Error (K) for June and July 2006 MM5 by Month and by State and Region in the 36 km Domain........................................ 3-9 Table 3-5. Temperature Error (K) for June and July 2006 MM5 by Month and by State in the 12 km Domain. ........................................................ 3-10 Table 3-6. Temperature Error (K ) for June and July 2006 MM5........................................ 3-10 Table 3-7. Mixing Ratio Bias (g /kg) for June and July 2006 MM5 by Month and by State and Region in the 36 km Domain...................................... 3-10 Table 3-8. Mixing Ratio Bias (g /kg) for June and July 2006 MM5 by Month and by State and Region in the 12 km Domain...................................... 3-11 Table 3-9. Mixing Ratio Bias (g/kg) for June and July 2006.............................................. 3-12 Table 3-10. Mixing Ratio Error (g/k g) for June and July 2006 MM5 by Month and by State and Region in the 36 km Domain...................................... 3-12F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc ii Table 3-11. Mixing Ratio Error (g/k g) for June and July 2006 MM5 by Month and by State and Region in the 12 km Domain...................................... 3-13 Table 3-12. Mixing Ratio Error (g/k g) for June and July 2006. ........................................... 3-13 Table 3-13. Wind Index of Agreement for June and July 2006 MM5 by Month and by State and Region in the 36 km Domain...................................... 3-13 Table 3-14. Wind Index of Agreement for June and July 2006 MM5 by Month and by State and Region in the 12 km Domain...................................... 3-14 Table 3-15. Wind Index of Agreemen t for June and July 2006............................................ 3-14 Table 5-1. Temperature Bias (K) For June and July 4 km MM5 Simulations. ......................................................................................................... 5-2 Table 5-2. Temperature Error (K) for June and July 4 km MM5 Simulations. ......................................................................................................... 5-2 Table 5-3. Mixing Ratio Bias (g/kg) for June and July 4 km MM5 Simulations. ......................................................................................................... 5-2 Table 5-4. Mixing Ratio Error (g/k g) for June and July 4 km MM5 Simulations. ......................................................................................................... 5-3 Table 5-5. Wind Index of Agreement for June and July 4 km MM5 Simulation............................................................................................................ 5-3

FIGURES

Figure 2-1 36/12/4 km MM5 Domain. .................................................................................. 2-4 Figure 3-1. Regional Planning Orga nization (RPO) Boundaries. ........................................ 3-15 Figure 3-2. Spatial Mean Temperat ure (Deg. C) for June 2006 within the 4 km Domain................................................................................................ 3-15 Figure 3-3. Spatial Mean Temperat ure (Deg. C) for July 2006 within the 4 km Domain................................................................................................ 3-16 Figure 3-4. Spatial Mean Mixing Ra tio (g/kg) for J une 2006 within the 4 km Domain...................................................................................................... 3-16 Figure 3-5. Spatial Mean Mixing Ra tio (g/kg) for Ju ly 2006 within the 4 km Domain...................................................................................................... 3-17 Figure 3-6. Spatial Mean Index of Agreement for June 2006 within the 4 km Domain ..................................................................................................... 3-17 Figure 3-7. Spatial Mean Index of Agreement for July 2006 within the 4 km Domain...................................................................................................... 3-18 Figure 3-8. Spatial Mean Wind Dir ection (deg.) for June 2006 within the 4 km Domain................................................................................................ 3-18 Figure 3-9. Vector Mean Wind Sp eed (m/s) for June 2006 wthin the 4 km Domain ......................................................................................................... 3-19 Figure 3-10. Spatial Mean Wind Di rection (deg.) for July 2006 within the 4 km Domain................................................................................................ 3-19 Figure 3-11. Vector Mean Wind Speed (m/s) for July 2006 within the 4 km Doma in......................................................................................................... 3-20 Figure 3-12. CPC Analyzed Precip itation for June 2006 over the 36 km Domain............................................................................................................... 3-20 Figure 3-13. MM5 Estimated Precipitation for June 2006 over the 36 km Domain............................................................................................................... 3-21F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc iii Figure 3-14. CPC Analyzed Precip itation for July 2006 over the 36 km Domain............................................................................................................... 3-21 Figure 3-15. MM5 Estimated Precipitation for July 2006 over the 36 km Domain............................................................................................................... 3-22 Figure 3-16. CPC Analyzed Precip itation for June 2006 over the 12 km Domain............................................................................................................... 3-22 Figure 3-17. MM5 Estimated Precipitation for June 2006 over the 12 km Domain............................................................................................................... 3-23 Figure 3-18. CPC Analyzed Precip itation for July 2006 over the 12 km Domain............................................................................................................... 3-23 Figure 3-19. MM5 Estimated Precipitation for July 2006 over the 12 km Domain............................................................................................................... 3-24 Figure 3-20. CPC Analyzed Precip itation for June 2006 over the 4 km Domain............................................................................................................... 3-24 Figure 3-21. MM5 Estimated Precipitation for June 2006 over the 4 km Domain............................................................................................................... 3-25 Figure 3-22. CPC Analyzed Precip itation for July 2006 over the 4 km Domain............................................................................................................... 3-25 Figure 3-23. MM5 Estimated Precipitation for July 2006 over the 4 km Domain............................................................................................................... 3-26 Figure 4-1. Radiosonde Sounding Comparison at Denver on 0Z 20 July 2006...................................................................................................................... 4-3 Figure 4-2. Radiosonde Sounding Comparison at Denver on 12Z 21 July 2006.............................................................................................................. 4-3 Figure 4-3. Radiosonde Sounding Comparison at Denver on 0Z 23 July 2006...................................................................................................................... 4-4 Figure 4-4. Radiosonde Sounding Comparison at Denver on 12Z 24 July 2006.............................................................................................................. 4-4 Figure 4-5. Radiosonde Sounding Comparison at Denver on 0Z 26 July 2006...................................................................................................................... 4-5 Figure 4-6. Radiosonde Sounding Comparison at Denver on 12Z 27 July 2006.............................................................................................................. 4-5 Figure 4-7. Radiosonde Sounding Comparison at Denver on 0Z 29 July 2006...................................................................................................................... 4-6 Figure 4-8. Radiosonde Sounding Comparison at Denver on 12Z 30 July 2006.............................................................................................................. 4-6F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 1-1 1 INTRODUCTION

Over the past decade, emergent requirements for direct numerical si mulation of urban and regional scale photochemical and secondary aeroso l air quality, spawned largely by particulate matter (PM 2.5 ), ozone and regional haze regulations, have led to intensified efforts to construct high-resolution emissions, meteorological and air quality modeling data bases. The concomitant increase in computational throughput of low-cost m odern scientific worksta tions has ushered in a new era of regional air quality modeling. It is now possible, for example, to exercise sophisticated mesoscale prognostic meteorologi cal models and Eulerian and Lagrangian photochemical/aerosol models, simulating ozone, sulfate and nitrate deposition, and secondary organic aerosols (SOA) across the entire United St ates (U.S.) or over discrete subregions for extended periods (e.g., calendar year).

One such model is the Pennsylvania State Univer sity/National Center for Atmospheric Research (PSU/NCAR) Mesoscale Model (MM5 ) (Dudhia, 1993; Grell et al., 1994: www.mmm.ucar.edu/mm5 ). MM5 is a limited-area, non-hydr ostatic, terrain-following model designed to simulate mesoscale atmospheric circul ation. The model is supported by several preand post-processing programs wh ich are referred to collectively as the MM5 modeling system.

This report describes an appl ication and performance evaluati on of MM5 for an atmospheric simulation of the June and July 2006 modeling pe riod for a modeling domain that covers the continental United States at a 36 km grid spacing, the Southwestern United States at 12 km grid spacing, and most of the State of Colorado at 4 km grid resolution. The purpose of the MM5 modeling is to develop meteorological inputs to support photochemical grid modeling for the Denver 8-hour ozone State Implementation Plan (SIP) attainment demonstration modeling.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 2-1 2 METHODOLOGY

The methodology for this approach is very stra ightforward. The basic methodology was to apply the MM5 model for June and July 2006 at the various grid resolutions (36 km, 12 km, and 4 km) and to then compare the model results (wind sp eeds, wind directions, temperatures, etc.) with available surface meteorological observations.

2.1 Model Selection and Application

Below we give a brief summary of the MM5 input data preparation procedure used for this two monthly meteorological modeling exercise.

Model Selection : The publicly available non-hydrostatic version of MM5 (version 3.7.4) was used for this modeling study. Preprocessor pr ograms of the MM5 modeling system including TERRAIN, REGRID, LITTLE_R, a nd INTERPF were used to develop model inputs.

Horizontal Domain Definition: The computational grid is pres ented in Figure 2-1. The outer 36 km domain (D01) has 165 x 129 grid cells, select ed to maximize the coverage of the ETA analysis region. The mid-scale 12 km domain (D02) has 187 x 157 grid cells, selected to maximize the coverage of the western region around Colorado. The inner 4 km domain (D03) has 151 x 136 grid cells, selected to maximize the coverage of th e Denver Metropolitan area as well as the mountain regions to the west and hi gh plains areas to the east of Denver. The projection was in Lambert Conformal Coordina tes (LCC) with the “national RPO” grid projection pole of 40 o , -97 o with true latitudes of 33 o and 45 o . The datum set was NWS-84.

Vertical Domain Definition: The MM5 modeling was based on 34 vertical layers from the surface to 100 mb (approximately 15 km above ground level) with an approximately 38 meter deep surface layer. The MM5 vertical domain is presented in both sigma and height coordinates in Table 2-1.

Topographic Inputs: Topographic information for the MM5 was developed using the NCAR and the United States Geological Survey (USGS) terr ain databases. The grid was based on the 2 min (~4 km) Geophysical Data Center gl obal data. Terrain data was in terpolated to the model grid using a Cressman-type objective analysis scheme. To avoid interpolating elevated terrain over water bodies, after the terra in databases were interpolated on to the MM5 grid, the NCAR graphic water body database was used to corr ect elevations over water bodies.

Vegetation Type and Land Use Inputs: Vegetation type and land use information was developed using the most recently released PSU/NCAR da tabases provided with the MM5 distribution. Standard MM5 surface characteristics corresponding to each land use category were employed.

Atmospheric Data Inputs: The first guess meteorological fields were taken from the NCAR ETA archives. Surface and upper-air observations us ed in the objective analyses, following theprocedures outlined by Stauffer and Seaman at PSU, were quality-inspected by MM5 preprocessors using automated gross-error checks and "buddy" checks. In addition, rawinsonde soundings were subject to vertic al consistency checks. The s ynoptic-scale data used for thisF:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 2-2 initialization (and in the analysis nudging discussed below) we re obtained from the conventional National Weather Service (NWS) twice-da ily radiosondes and 3-hourly NWS surface observations.

Water Temperature Inputs: The ETA database contains a “skin temperature” field. This can be and was used as the water temperature input to these MM5 simulations. Past studies have shown that these skin temperatures, used as the water temperature surrogates, can lead to temperature errors along coastlines. However, for this analysis which focuses on bulk continental scale transport across the central United States, this issue is likely not important and the skin temperatures were used.

FDDA Data Assimilation: This simulation used analysis ba sed nudging. For these simulations analysis nudging coefficients of 2.5x10 -4 and 1.0x10 -4 were used for winds and temperature.

Physics Options : The MM5 model physics options were employed in this analysis as follows:

• Kain-Fritsch 2 Cumulus Parameterization on 36/12 km Domain;

• No Cumulus Parameterization on 4 km Domain;

• Pleim-Xiu Land Surface Model (LSM) and Asymmetric Convective Mixing (ACM) Planetary Boundary Layer (PBL) Schemes;

• Reisner 2 Mixed Phase Moisture Scheme; and

• RRTM Atmospheric Radiation Scheme

Application Methodology : The MM5 model was executed in 5- day blocks initialized at 12 GMT every 4 days with a 90 second time step. Model results were output ever y 60 minutes and output files were split at 24 hour intervals. Twelve (12) hours of spin-up was included in each 4-day block before the data was used in this atmos pheric simulation and subsequent evaluation. The model was run with 36 km and 12 km resolution nests with light smoothing feedback and the 4 km grid as a one-way nest.

2.2 Evaluation Approach

The model evaluation approach was based on a combination of qualitative and quantitative analyses. The qualitative appr oach was to compare the model estimated monthly total precipitation with the monthly Center for Pred iction of Climate (CPC) precipitation analysis using graphical outputs. The statistical approach was to examine tabulations of the model bias and error for temperature, and mixing ratio and the index of agreement for the wind fields and compare these to similar 36 km, 12 km, and 4 km simulations.

Interpretation of bulk statistics over a continenta l or regional scale domain is problematic. To detect if the model is missing important sub-regiona l features is difficult. For this analysis the statistics were performed on a state by state ba sis, a Regional Planning Organization (RPO) basis, and on a domain-wide for the continental 36 km domain and the re gional 12 km domain. For the 4 km domain, the statistics were genera ted for the area covere d by the domain which is most of Colorado. As with the continenta l scale and regional s cale calculations, the interpretation of the statistics may be problem atic given the significan t differences across the State in elevation and microclimates. Nonetheless, these statistics are offered as some measure of the quality of the data set generated.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 2-3 The observed database for winds, temperature, and water mixing ratio used in this analysis was the NOAA Forecast Systems Lab (FSL) MADIS surf ace observations. The rain observations are taken from the CPC retrospective rainfall archives available at: http://www.cpc.ncep.noaa.gov/produc ts/precip/realtime/retro.shtml

.

Table 2-1. MM5 Vertical Domain Specification.

.k(MM5) Sigma Pressure.(mb) Height(m) Depth(m)

34 0.000 10000 15674 2004 33 0.050 14500 13670 1585 32 0.100 19000 12085 1321 31 0.150 23500 10764 1139 30 0.200 28000 9625 1004 29 0.250 32500 8621 900 28 0.300 37000 7720 817 27 0.350 41500 6903 750 26 0.400 46000 6153 693 25 0.450 50500 5461 645 24 0.500 55000 4816 604 23 0.550 59500 4212 568 22 0.600 64000 3644 536 21 0.650 68500 3108 508 20 0.700 73000 2600 388 19 0.740 76600 2212 282 18 0.770 79300 1930 274 17 0.800 82000 1657 178 16 0.820 83800 1478 175 15 0.840 85600 1303 172 14 0.860 87400 1130 169 13 0.880 89200 961 167 12 0.900 91000 794 82 11 0.910 91900 712 82 10 0.920 92800 631 81 9 0.930 93700 550 80 8 0.940 94600 469 80 7 0.950 95500 389 79 6 0.960 96400 310 78 5 0.970 97300 232 78 4 0.980 98200 154 39 3 0.985 98650 115 39 2 0.990 99100 77 38 1 0.995 99550 38 38 0 1.000 100000 0 0F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 2-4 -2880-2520-2160-1800-1440-1080 -720 -360 0 360 720 1080 1440 1800 2160 2520 2880 -2160 -1800 -1440 -1080

-720 -360 0 360 720 1080 1440 1800 2160

MM5 36 km MM5 12km MM5 4km

36 km: 165 x 129 dot points (-2952, -2304) to (2952, 2304) 12 km: 187 x 157 dot points (-1836, -936) to ( 396, 936) 04 km: 151 x 136 dot points ( -984, -324) to ( -384, 216) 

### Denver MM5 Domain

Figure 2-1. 36/12/4 km MM5 Domain.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-1 

### 3 MM5 PERFORMANCE EVALUATION RESULTS

Both quantitative and qualitative model evaluati on results of the MM5 meteorological modeling for the overall region at the 36 km, 12 km, and 4 km grid spacing are presen ted in this section.

3.1 Quantitative Model Evaluation Results

Statistical model evaluation results are presente d in this section. A nested, muli-month model evaluation is very difficult to summarize in a singl e document. With this in mind, this section presents results so potential data users can independently judge the adequacy of the model simulation. Overall comparisons ar e offered herein to judge the model efficacy, but this review does not necessarily cover all potential user needs and applications.

Tables 3-1 through 3-15 present the statistical metr ics for each state, for each Regional Planning Organization (RPO) area as appropr iate, and for the full area as a portion of the United States that is covered by each of the 36 km, 12 km, and 4 km modeling domains (called “ALL” in each table). For reference, a graphic of RPO boundaries is presented in Figure 3-1 and the individual boundaries of the domains are presen ted in Figure 2-1. In these comparisons the vertical level 1 (~19 m) model estimates are compared directly w ith the nominal ~2 m temperature and moisture and ~10 m wind measurements.

To evaluate the performance of the MM5 2006 36 km, 12 km, and 4 km simulations for the U.S., for the western U.S., and for Colorado, respecti vely, a number of performance benchmarks for comparison were used. Emery and co-workers ( 2001), have derived and pr oposed a set of daily performance “benchmarks” for typical meteorol ogical model performance. These standards were based upon the evaluation of about 30 MM 5 and RAMS meteorological simulations in support of air quality applications performed over several years and reported by Tesche et al. (2001). The purpose of these benc hmarks was not to give a passi ng or failing grade to any one particular meteorological model application, but rath er to put its results in to the proper context of other models and meteorological data sets. Th e key to the benchmarks is to understand how good or poor the results are relative to other mode l applications run for the U.S. Thus, this section compares the calculated statistical meas ures against these benchmarks to assess the MM5 performance in terms of its viability for use in modeling and meteorological assessments and Section 4 presents a comparison to other simila r model applications. These benchmarks include bias and error in temperature and mixing ratio as well as the Wind Speed Index of Agreement (IA) between the models and data bases. The be nchmark for acceptability for each variable is:

• Temperature bias: <±0.5 K

• Temperature error: <2.0 K

• Mixing ratio bias: <±1.0 g/kg

• Mixing ratio error: <2.0 g/kg

• Wind Speed Index of Agreement (IA): 0 = worst, 1 = best, 0.6 = acceptableF:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-2 3.1.1 Temperature Bias and Error

Temperature bias statistics are presented in Tabl es 3-1 through 3-3 for the 36 km, 12 km, and 4 km modeling domains. Each is evaluated in turn.

Temperature bias statistics are presented in Ta ble 3-1 for the 36 km modeling domain. As can be seen in Table 3-1, when the temperatures are averaged over the June-July 2006 period for the entire modeling domain (ALL), the model has a bias of -0.12 K, thus underestimating on average temperature across the U.S. In reviewing thes e results on a state-by-st ate and region-by-region basis, the most obvious trend is that the western states and a handful of Ea stern Coastal states (Florida, New York, Virginia, and Rhode Island) are underestimated by a fe w tenths of a degree Kelvin (guideline within the +/- 0.5 K benchmark) up to a bias of -2.13 K in California with several western states being just outside of the guid eline range (Arizona, Colorado, Nevada, New Mexico, Wyoming, Montana, and Oregon ranging fr om -0.59 to -1.42 K). All other states and regional RPOs have temperature bias on the pos itive side generally within the guideline benchmark. Differences between June and July 2006 temperature bias is generally insignificant indicating that the above observa tions on the June-July 2006 aver ages hold for each individual month’s performance review as well.

Temperature bias statistics are presented in Table 3-2 for the 12 km domain. As can be seen in Table 3-2, when the temperatures are averaged over the June-July 2006 period for the entire 12 km modeling domain (ALL), the model has a s light negative bias of -0.01 K for the 12 km domain, which is an improvement over the 36 km results. As with the 36 km Western U.S. temperature bias, most of the states within the 12 km domain have bias that is slightly negative and within the guideline benchmark bias, except fo r Nevada (with -0.73 K). Little difference was discerned between the June and July 2006 bias for each state reported in the 12 km domain in Table 3-2 except for Utah with a positive bias in June (0.40 K) and a negative bias in July (- 0.09 K), both of which were within guidelines.

Temperature bias statistics are presented in Table 3-3 for the 4 km domain. As can be seen in Table 3-3, when the temperatur e biases are averaged over the June-July 2006 period for the entire 4 km Colorado modeling domain (Mean), the model has a bias of -0.20 K. The model has a negative temperature bias in June 2006 and a po sitive temperature bias in July 2006 over the 4 km domain. Both months were within the guide line range of the temperature bias threshold of <±0.5 K for the 4 km domain.

Temperature error data are presented in Table 3-4 for the 36 km modeli ng domain. The overall temperature error (ALL category) over all states and for the J une-July 2006 period is 1.53 K on the 36 km domain. All mean annual temperature errors over each state and region were in the range from the lowest value of 0.84 K in Delaware to the highest error of 3.05 K in Nevada. Far Western states in the vicinity of Colorado were all generally greater than the benchmark of 2.0 K including Arizona, Colorado, Nevada, Wyoming, Idaho, California, Or egon, and Utah with exception of New Mexico, Montana, and Washi ngton. The average of the WRAP RPO states was 2.30 K. All other states and RPOs for this June-July 2006 period had temperature errors less than the benchmark over the 36 km domain. Most individual monthly temperature errors mimicked the Mean results (guideline perfor mance) except for the Montana July 2006 temperature error which was 2.13 K.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-3 Temperature error data are presented in Table 3-5 for the 12 km grid spaced western area modeling domain. The overall temperature erro r over the June-July 2006 period (Mean) for the 12 km domain (ALL category) was 1.42 K which is a slight improvement over the 36 km domain results. On a state by state basis for those in th is western 12 km domain, all states improved in terms of their temperature error (had errors le ss than the 36 km do main) although two states, namely, Colorado and Nevada (2.06 and 2.05 K, re spectively) were slightly just above the guideline benchmark.

Temperature error data are presented in Tabl e 3-6 for the 4 km modeling domain. The overall June-July 2006 temperature error (Mean) is 1.78 K. Both months were within the guideline benchmark for the 4 km domain.

3.1.2 Mixing Ratio Bias and Error

Mixing ratio bias data are presented in Table 3-7 for the 36 km modeling domain. Averaged over the June-July 2006 period, over all states, the model has a bias of 0.10 g/kg for the 36 km domain as shown by the “ALL” category in Table 3-7. The MM5 model results were well within the guideline range of the mixing ratio threshold of ±1.0 g/kg for all states and RPOs. The range of underprediction bias was from a low of -0.71 g/kg in Idaho to -0.1 g/ kg in California and the range of overprediction bias was from a lo w of 0.00 g/kg in Tennessee to 0.68 g/kg in New Mexico. Regional tendencies that were evid ent over the 36 km domain was that most Midwestern states around or adjacent to the Ohio River Valley all had negative mixing ratio bias and extreme Southwestern states had the highest pos itive mixing ratio bias. Little June to July variations in the mixing ratio bias were evid ent across most states although a few states had higher changes in bias (e.g., Arizona from 1.06 in June to 0.26 g/kg in July and New Mexico from 1.32 in June to 0.04 g/kg in July0 and othe rs had swings from positive to negative mixing ratio bias (e.g., Colorado from 0.39 in June to -0 .94 g/kg in July and Montana from -0.42 in June to 0.45 g/kg in July). Only two states, namel y, Arizona and New Mexico, had June values (1.06 and 1.32, respectively) greater th an the benchmark of ±1.0 g/kg.

Mixing ratio bias data are pres ented in Table 3-8 for the 12 km modeling domain. As can be seen in Table 3-8, when the mixing ratio biases are averaged over the June-July 2006 period for the entire 12 km modeling domain (ALL), the m odel has a slight positive bias of 0.09 g/kg for the 12 km domain, which is a bout the same as for the 36 km domain results. For these southwestern states the mixing ratio biases were all well within the guideline range of the benchmark of ±1.0 g/kg with slight improvement in bias in some states a nd slight degradation of bias in other states.

Mixing ratio bias data are presented in Table 3-9 for the 4 km modelin g domain. The overall June-July 2006 mixing ratio bias (Mean) is 0.18 g/kg averaged over 4 km domain. As with the 36 km and 12 km results for Colorado, the mixing ratio changed from a June positive bias of 0.86 g/kg to a July negative bias of -0.45 g/kg. All mixing ratio bias was well within the acceptability benchmark of ±1.0 g/kg.

Mixing ratio error results are pres ented in Table 3-10 for the 36 km domain. The mean error for the June-July 2006 data set was 1.33 g/kg for the whole 36 km domain (ALL). The range of Mean errors was from a low of 0.94 g/kg in Main e to a high of 1.83 g/kg in New Mexico. The model shows a mean error throughout the year in each state and RPO that is within the guidelineF:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-4 benchmark value of 2.0 g/kg. A comparison of the values of mean error for each state and RPO over both June and July show little difference.

Mixing ratio error results are pres ented in Table 3-11 for the 12 km domain. The mean error for the June-July 2006 data set for the 12 km do main was 1.51 g/kg. The 12 km grid domain modeling shows mean mixing ratio errors that are gene rally within the guideline value of 2.0 g/kg. For New Mexico, the June 12 km value wa s 2.13 g/kg. The monthly va lues of mean error are highest for July 2006 MM5 results except for New Mexico.

Mixing ratio error results are pr esented in Table 3-12 for the 4 km domain. The mean mixing ratio error is 1.64 g/kg for the 4 km modeling domai n. The mixing ratio errors for June and July 2006 were similar and were 1.60 to 1.68 g/kg, resp ectively. These errors while appearing to degrade from the 36 km to the 12 km to the 4 km domains actually were about the same when considering the performance in Colorado rang ing from 1.59 to 1.70 to 1.68 over the various domains of the MM5 model degraded somewhat ove r the from the 36 km The model shows that all mixing ratio error values were within the acceptability benchmark of 2.0 g/kg.

3.1.3 Wind Index of Agreement

Comparisons between the June-July 2006 36 km, 12 km, and 4 km domain MM5 modeling of winds and those of the NOAA Forecast Systems Lab (FSL) MADIS surface observations were made using the Wind Index of Agreement (IA). Recall that the benckmark is a Wind Speed Index of Agreement equal to 0.6. Values belo w that benckmark are generally poor agreement and values above that benchmark are better with an IA of 1.0 being the best. Note also that the Index of Agreement metric is sensitive to the nu mber of monitors being used in the calculation, with more monitors tend ing to give higher Index of Agreement scores.

The Wind IAs for the 36 km domain are presen ted in Table 3-13. The domain-wide June-July 2006 averaged Wind IA is 0.89 for the 36 km domai n. No significant monthly differences were noted between June and July in any one state or RPO. For all states and RPOs except New Hampshire (0.44), Vermont (0.56), Connecticut (0.56), and Delaware (0.51), the Wind IA fell in the guideline (0.6) to best (1.0) range of comparison. For the We stern states the Wind IA ranged from 0.75 to 0.81 for each state and the WRAP RPO was 0.88.

The Wind IAs for the 12 km modeling domain are presented in Table 3-14. The June-July 2006 average Wind IA is 0.88 for the 12 km domain. Fo r all states and months in the 12 km domain, the Wind IA fell in the guideline (0.6) to best (1.0) ra nge of comparison. Specifically for the 12 km states the Wind IA ranged from 0.75 to 0.81 showing very good wind agreement for each

state.

The Wind IAs for the 4 km modeling domain are presented in Table 3-15. The June-July 2006 average Wind IA is 0.83 for the 4 km domain. The wind IA for each month was about the same at 0.83 and 0.84, respectively.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-5 3.1.4 Spatial Mean Temperature and Mixing Ratio

This section presents spatial mean time series plots on a monthly basis for both temperature and mixing ratio for the 4 km modeling domain. The “observed” (shown by a “ * ” in the figures) spatial mean temperature or mixing ratio was computed for each hour by averaging all valid observed station data within the modeling domain (30-40 stations). The “model” estimated spatial mean (solid red line in the figures) wa s computed for each hour by averaging the model estimates at all station locations that reported va lid data for that hour. These 4 km domain-wide hourly averages for observed and modeled temperat ure and mixing ratio data were then plotted versus time to demonstrate the comparison of th e two sets of data and allow a qualitative evaluation of the MM5 data. These straightfo rward plots were useful for discerning overall trends in model performance and provide a c onvenient tool to quickly identify if the MM5 Model is tending to over or underestimate modeled fields.

Figures 3-2 and 3-3 present the spatial mean te mperatures by month within the 4 km modeling domain. Review of these two June and July 2006 mean spatial temperat ure profiles indicates that the MM5-generated temper ature fields capture the synopt ic and diurnal trends of temperature across the domain quite well. This is shown by noting the general agreement in the patterns of temperature for the modeled and observe d values as a function of time. Also shown in these patterns is the general good agreemen t of the MM5 model in following the diurnal pattern of the temperatures. The greatest diffe rences in temperatures are noted where the MM5 data underpredict the high peak temperatures an d overpredict the low peak temperatures. The model versus observed temperatures are generally within a few degrees of the observed values.

Figures 3-4 through 3-5 present th e spatial mean mixing ratios ove r the 4 km modeling domain. Review of the mean spatial mixing ratio prof iles for June and July 2006 indicate the MM5- generated mixing ratio fields captu re the synoptic trends as well as the diurnal patterns across the domain quite well. This is s hown in the figures by noting the ge neral agreement in the patterns of mixing ratio as a function of time over each month. Although this general trend was estimated well by the MM5 data, some underestimation and ove restimation was noted in some periods of time. More overestimates were made by the model in June (Figure 3-4) when mixing ratios were lower (of the two months) and more underestimates in July 2006 (Figure 3-5) when the mixing ratios were higher.

3.1.5 Spatial and Temporal Mean Wind Speed I ndex of Agreement, Wind Speed and Wind Direction

This section presents spatial mean time series plots on a monthly basis for the Wind Speed Index of Agreement (IA), wind speed, and wind directi on. The model estimated spatial wind speed IA was computed for each hour by averaging the mode l estimates at all station locations that reported valid data for that hour and compari ng those to observed data . The IA provides a measure of the quantitative comparability. Th e mean wind speeds were computed using the calculated vector averaged hour ly domain-wide observed and m odeled data. The “observed” spatial vector averaged wind speed was comput ed for each hour by averaging all valid observed station wind speed data within the modeling domain (30-40 stat ions). The “model” estimated spatial wind speed was computed for each hour by averaging the model estimates at all station locations that reported valid data for that hour. The mean wind direction wa s calculated from theF:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-6 hourly domain-wide averaged observed versus m odeled data similar to the wind speeds. These domain-wide hourly averages of wind speed IA, vector wind speed, and m ean wind direction for observed and modeled data were then plotted ve rsus time to demonstrate the comparison of the two sets of data. This allowed a qualitative evaluation of the MM5 data performance as compared to the average observed data. These st raightforward plots were useful for discerning overall trends in model performance and provide a convenient tool to quickly identify if the MM5 Model is tending to over or underestimate modeled fields.

Figures 3-6 and 3-7 provide the spatial mean of the Wind Speed Index of Agreement as a function of time over the 4 km domain for June and July 2006 simulations. In both plots the IA is generally greater than the minimum guideline benchmark of 0.6 with a few exceptions in midJune and mid to late July. The diurnal patte rn indicates that MM5 performs best during the daylight hours where the IA is highest and poorest in the nighttime hours when wind speeds are lower.

Figure 3-8 provides the spatial m ean profiles of the wind direct ions for modeled and observed data as a function of time over the 4 km domain for the June 2006 simulations. Review of the June wind direction plots indica te the spatially averaged MM5 generated wind direction fields capture the synoptic trends of wind direction ac ross the domain quite well. This is shown by noting the general agreement in the patterns of wind direction between the observed and modeled data as a function of time. Also shown in th ese patterns is the general good agreement of the MM5 model in following the diurnal pattern of wind direction for each day. The agreement between the observations and modeled wind directio ns were best when winds were persistent, e.g., June 13-15 where modeled and obser ved values were within about 5-10 o of each other. On days when diurnal variations were significant the MM5 wind di rection averages tend to miss some of the daily wind shifts by 50-90 o but still follow the general pa ttern of change over several days to weeks.

Figure 3-9 provides the spatial mean profiles of the wind speeds for modeled and observed data as a function of time over the 4 km domain for the June 2006 simulations. Review of the June wind speed plots indicate the spatially averaged MM5 generated wind speeds fields capture the synoptic trends of wind direction across the do main quite well. This is shown by noting the general agreement in the patterns of wind speed between the observed and modeled data as a function of time. Also shown in these patterns is the general good agreement of the MM5 model in following the diurnal pattern of wind speed fo r each day. Where wind speeds are lowest the model tends to overpredi ct the speeds compared to observ ed values. The MM5 model did particularly well in calculati ng the high values on June 15.

Figures 3-10 and 3-11 provide the spatial mean profiles of the wind directions and wind speeds for modeled and observed data as a function of time over the 4 km domain for the July 2006 simulations. Review of the July wind direct ion and wind speed plots indicate the spatially averaged MM5 generated wind direction fields ca pture the synoptic and di urnal trends across the domain quite well. Other comparisons are similar to those for June noted above.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-7 3.2 Qualitative Monthly Precipitation Analysis

This section presents qualitative comparisons of MM5 estimated precipitation with the CPC retrospective analysis data. When comparing the CPC and MM5-generated precipitation data, note should be taken that the CPC analysis covers only the Contin ental U.S. and does not extend offshore or into Canada or Me xico. The MM5 fields, on the ot her hand, cover the entire 36 km domain. Also note that the CPC analysis is based on a 0.25 x 0.25 degree (~40 x 40 km) grid and the MM5 is based on a comparable grid of 36 x 36 km and much finer grids of 12 x 12 km, and 4 x 4 km. Neither the 40km or 36 km grid spacing capture small precipitation features effectively, while both the 12 km and 4 km grid spacing will capture and di splay such features.

Total precipitation comparisons fo r June and July 2006 over the 36 km domain are presented in Figures 3-12 through 3-15. For each month, the fi rst plot presents the CPC analysis data (e.g., Figure 3-12) and the second plot represents the MM5 total preci pitation (e.g., Figure 3-13). Given that the CPC analysis da ta are considered to be the standard for precipitation, MM5 provides a reasonable representation of the sp atial distribution of precipitation over the contiguous U.S. for June and July of 2006. The poorest agreement is in the southwest U.S. for both months where the MM5 precipitation estima tes are much greater across Nevada, Colorado, Utah, Wyoming, Arizona, and New Mexico. In June MM5 precipitation is heavier along the south east coast than CPC and in Montana and New Mexico. The July MM5 pattern is similar to CPC but the MM5 results are much higher in the Southeast U.S. a nd in the terrain induced high intensity precipitation over New Mexico. The MM5 model treats more specifically the terrain which leads to the potential differences in the MM 5 results in the Rockies in the summertime.

Total precipitation comparisons fo r June and July 2006 over the 12 km domain are presented in Figures 3-16 through 3-19. As with the 36 km simulations, the MM5 data provide a more refined treatment of terrain-i nduced precipitation a nd therefore in the mountainous Southwest U.S. more widespread precipita tion is calculated. In both the June and July 2006 periods the MM5 results are higher in magnitude and spatial ex tent of the precipitation. The refinement of the 12 km grid size is obvious when compari ng the CPC precipitation to that of the MM5 simulations as the MM5 graphics app ear to have much finer detail.

Total precipitation compar isons for June and July 2006 over th e 4 km domain are presented in Figures 3-20 through 3-21. With in the spatial limitations of th e CPC analysis data, MM5 does a reasonably good job representing the general spatia l coverage of the preci pitation shown in the CPC data. The MM5 plots show much more pr ecipitation over the central Colorado Rockies in both months than CPC data. Much higher and widespread precipitation was estimated by MM5 in June. The July simulations did well in findi ng the rainshadow over central Colorado along the western edge of the front range but gave mu ch higher precipitation over western Colorado.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-8 Table 3-1. Temperature Bias (K) for June and July 2006 MM5 by Month and by State and Region in the 36 km Domain. Region June '06 July '06 Mean AL 0.25 -0.04 0.11 ALL -0.08 -0.15 -0.12 AR 0.42 0.18 0.30 AZ -0.67 -0.72 -0.70 CA -2.02 -2.25 -2.13 CENRAP 0.19 0.04 0.11 CO -1.17 -0.82 -1.00 CT 0.17 0.25 0.21 DE 0.17 0.28 0.22 FL -0.19 -0.05 -0.12 GA 0.21 0.01 0.11 IA 0.48 0.44 0.46 ID -0.37 -0.05 -0.21 IL 0.57 0.48 0.52 IN 0.49 0.42 0.45 KS 0.10 0.07 0.09 KY 0.48 0.31 0.39 LA 0.37 0.38 0.38 MA 0.02 0.11 0.06 MANE_VU 0.03 0.10 0.06 MD 0.00 0.01 0.00 ME 0.06 0.06 0.06 MI 0.17 0.19 0.18 MN 0.32 0.12 0.22 MO 0.22 0.06 0.14 MS 0.46 0.21 0.34 MT -0.54 -0.64 -0.59 MW 0.48 0.40 0.44 NC 0.31 0.08 0.19 ND 0.37 0.51 0.44 NE 0.09 0.10 0.09 NH 0.46 0.66 0.56 NJ 0.00 0.16 0.08 NM -0.72 -0.56 -0.64 NV -0.95 -1.11 -1.03 NY -0.25 -0.24 -0.25 OH 0.43 0.35 0.39 OK 0.34 0.03 0.19 OR -1.13 -1.03 -1.08 PA 0.16 0.23 0.19 RI -0.03 -0.12 -0.07 SC 0.29 0.19 0.24 SD 0.22 0.20 0.21 TN 0.48 0.36 0.42 TX -0.11 -0.32 -0.22 UT -0.17 -0.79 -0.48 VA -0.11 -0.05 -0.08 VISTAS 0.16 0.07 0.11 VT 0.01 0.03 0.02 WA -0.52 -0.40 -0.46 WI 0.82 0.62 0.72 WRAP -1.02 -1.02 -1.02 WV 0.33 0.36 0.35 WY -1.47 -1.38 -1.42F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-9 Table 3-2. Temperature Bias (K) for June and July 2006 MM5 by Month and by State in the 12 km Domain.

Region June '06 July '06 Mean ALL 0.02 -0.04 -0.01 AZ -0.41 -0.43 -0.42 CO -0.60 -0.20 -0.40 ID 0.13 0.31 0.22 NM -0.47 -0.27 -0.37 NV -0.67 -0.78 -0.73 UT 0.40 -0.09 0.16 WY -0.52 -0.43 -0.47

Table 3-3. Temperature Bias (K) for June and July 2006 MM5 in the 4 km Domain. Region June '06 July '06 Mean ALL -0.42 0.01 -0.20

Table 3-4. Temperature Error (K) for June and July 2006 MM5 by Month and by State and Region in the 36 km Domain. Region June '06 July '06 Mean AL 1.49 1.51 1.50 ALL 1.53 1.54 1.53 AR 1.21 1.30 1.25 AZ 2.11 2.14 2.13 CA 2.94 3.16 3.05 CENRAP 1.29 1.27 1.28 CO 2.79 2.54 2.66 CT 1.19 1.20 1.20 DE 0.85 0.83 0.84 FL 1.55 1.42 1.48 GA 1.35 1.34 1.35 IA 1.26 1.19 1.23 ID 1.90 2.39 2.14 IL 1.20 1.19 1.20 IN 1.12 0.99 1.06 KS 1.20 1.14 1.17 KY 1.09 0.99 1.04 LA 1.65 1.45 1.55 MA 1.19 1.12 1.15 MANE_VU 1.22 1.23 1.23 MD 1.28 1.30 1.29 ME 1.07 1.12 1.10 MI 1.50 1.41 1.45 MN 1.35 1.40 1.38 MO 1.14 1.12 1.13 MS 1.31 1.21 1.26 MT 1.72 2.13 1.93 MW 1.34 1.30 1.32 NC 1.30 1.23 1.26 ND 1.21 1.39 1.30 NE 1.30 1.29 1.29 NH 1.74 1.92 1.83 NJ 1.14 1.14 1.14 NM 1.93 1.73 1.83 NV 2.32 2.55 2.43 NY 1.28 1.27 1.27F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-10 Region June '06 July '06 Mean OH 1.17 1.14 1.15 OK 1.27 1.30 1.28 OR 1.96 2.19 2.08 PA 1.12 1.08 1.10 RI 1.20 1.28 1.24 SC 1.11 1.04 1.08 SD 1.47 1.54 1.50 TN 1.25 1.30 1.27 TX 1.23 1.18 1.20 UT 2.22 2.43 2.33 VA 1.31 1.23 1.27 VISTAS 1.35 1.29 1.32 VT 1.31 1.36 1.34 WA 1.60 1.81 1.70 WI 1.45 1.49 1.47 WRAP 2.23 2.37 2.30 WV 1.35 1.28 1.32 WY 2.38 2.55 2.47

Table 3-5. Temperature Error (K) for June and July 2006 MM5 by Month and by State in the 12 km Domain.

Region June '06 July '06 Mean ALL 1.41 1.43 1.42 AZ 1.65 1.57 1.61 CO 2.19 1.92 2.06 ID 1.54 2.00 1.77 NM 1.69 1.48 1.59 NV 1.95 2.14 2.05 UT 1.86 1.93 1.89 WY 1.76 1.92 1.84

Table 3-6. Temperature Error (K) for June and July 2006 MM5. Region June '06 July '06 Mean ALL 1.93 1.64 1.78

Table 3-7. Mixing Ratio Bias (g/kg) for June and July 2006 MM5 by Month and by State and Region in the 36 km Domain. Region June '06 July '06 Mean AL 0.54 0.64 0.59 ALL 0.15 0.05 0.10 AR -0.23 0.04 -0.09 AZ 1.06 0.26 0.66 CA -0.01 -0.02 -0.01 CENRAP 0.07 0.18 0.13 CO 0.39 -0.94 -0.28 CT 0.23 -0.18 0.02 DE 0.13 -0.36 -0.12 FL 0.70 0.17 0.44 GA 0.38 0.25 0.31 IA -0.31 -0.38 -0.34 ID -0.76 -0.66 -0.71 IL -0.24 -0.31 -0.28 IN -0.40 -0.39 -0.39F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-11 Region June '06 July '06 Mean KS 0.24 0.25 0.25 KY 0.14 -0.42 -0.14 LA 0.63 0.57 0.60 MA 0.35 0.14 0.25 MANE_VU 0.38 0.02 0.20 MD 0.39 -0.13 0.13 ME 0.37 0.01 0.19 MI -0.12 0.00 -0.06 MN -0.36 0.01 -0.18 MO -0.04 0.00 -0.02 MS 0.40 0.50 0.45 MT -0.42 0.45 0.02 MW -0.17 -0.11 -0.14 NC 0.50 0.04 0.27 ND -0.05 0.40 0.17 NE 0.34 0.17 0.25 NH 0.44 0.03 0.23 NJ 0.41 -0.02 0.19 NM 1.32 0.04 0.68 NV 0.20 0.03 0.12 NY 0.33 0.06 0.20 OH -0.05 -0.11 -0.08 OK -0.40 0.03 -0.19 OR -0.22 0.24 0.01 PA 0.52 0.07 0.29 RI 0.13 -0.01 0.06 SC 0.55 0.09 0.32 SD 0.47 0.61 0.54 TN 0.13 -0.13 0.00 TX 0.57 0.54 0.56 UT -0.38 -0.18 -0.28 VA 0.10 -0.51 -0.20 VISTAS 0.43 0.05 0.24 VT 0.41 -0.10 0.16 WA -0.34 0.09 -0.13 WI -0.16 0.08 -0.04 WRAP 0.10 -0.01 0.05 WV 0.48 -0.16 0.16 WY -0.13 0.18 0.03

Table 3-8. Mixing Ratio Bias (g/kg) for June and July 2006 MM5 by Month and by State and Region in the 12 km Domain.

Region June '06 July '06 Mean ALL 0.11 0.06 0.09 AZ 1.01 0.15 0.58 CO 0.53 -0.93 -0.20 ID -0.54 -0.43 -0.49 NM 1.37 0.02 0.69 NV 0.18 0.00 0.09 UT -0.36 -0.27 -0.31 WY 0.01 0.31 0.16F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-12 Table 3-9. Mixing Ratio Bias (g/kg) for June and July 2006. Region June '06 July '06 Mean ALL 0.81 -0.45 0.18

Table 3-10. Mixing Ratio Error (g/kg) for June and July 2006 MM5 by Month and by State and Region in the 36 km Domain

. Region June '06 July '06 Mean AL 1.52 1.55 1.53 ALL 1.25 1.41 1.33 AR 1.28 1.62 1.45 AZ 1.54 1.74 1.64 CA 1.09 1.34 1.22 CENRAP 1.37 1.50 1.43 CO 1.40 1.77 1.59 CT 0.91 1.24 1.08 DE 0.97 1.47 1.22 FL 1.52 1.36 1.44 GA 1.65 1.77 1.71 IA 1.31 1.61 1.46 ID 1.31 1.49 1.40 IL 1.20 1.50 1.35 IN 1.28 1.34 1.31 KS 1.36 1.46 1.41 KY 1.25 1.44 1.35 LA 1.59 1.50 1.55 MA 0.85 1.10 0.98 MANE_VU 0.95 1.20 1.08 MD 1.01 1.39 1.20 ME 0.90 0.99 0.94 MI 0.96 1.13 1.04 MN 1.16 1.38 1.27 MO 1.16 1.29 1.22 MS 1.56 1.58 1.57 MT 1.12 1.30 1.21 MW 1.08 1.29 1.18 NC 1.36 1.53 1.44 ND 1.12 1.38 1.25 NE 1.35 1.35 1.35 NH 0.94 1.08 1.01 NJ 1.08 1.44 1.26 NM 1.99 1.66 1.83 NV 1.01 1.42 1.21 NY 0.90 1.13 1.01 OH 1.08 1.22 1.15 OK 1.49 1.62 1.56 OR 0.93 1.13 1.03 PA 1.04 1.30 1.17 RI 0.93 1.22 1.08 SC 1.40 1.37 1.38 SD 1.18 1.36 1.27 TN 1.26 1.36 1.31 TX 1.53 1.58 1.56 UT 1.31 1.55 1.43 VA 1.18 1.66 1.42 VISTAS 1.40 1.51 1.45 VT 0.96 1.07 1.01F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-13 Region June '06 July '06 Mean WA 0.90 1.03 0.96 WI 1.02 1.28 1.15 WRAP 1.21 1.40 1.31 WV 1.08 1.20 1.14 WY 1.20 1.27 1.24

Table 3-11. Mixing Ratio Error (g/kg) for June and July 2006 MM5 by Month and by State and Region in the 12 km Domain

.

Region June '06 July '06 Mean ALL 1.42 1.61 1.51 AZ 1.59 1.90 1.75 CO 1.55 1.85 1.70 ID 1.29 1.51 1.40 NM 2.13 1.85 1.99 NV 1.06 1.60 1.33 UT 1.40 1.73 1.57 WY 1.30 1.41 1.36

Table 3-12. Mixing Ratio Error (g/kg) for June and July 2006. Region June '06 July '06 Mean ALL 1.60 1.68 1.64

Table 3-13. Wind Index of Agreement for June and July 2006 MM5 by Month and by State and Region in the 36 km Domain. Region June '06 July '06 Mean AL 0.72 0.73 0.73 ALL 0.90 0.88 0.89 AR 0.70 0.70 0.70 AZ 0.75 0.75 0.75 CA 0.80 0.78 0.79 CENRAP 0.87 0.87 0.87 CO 0.80 0.80 0.80 CT 0.56 0.57 0.56 DE 0.50 0.52 0.51 FL 0.79 0.79 0.79 GA 0.68 0.69 0.69 IA 0.74 0.71 0.73 ID 0.79 0.78 0.78 IL 0.72 0.74 0.73 IN 0.65 0.68 0.66 KS 0.78 0.76 0.77 KY 0.65 0.62 0.63 LA 0.67 0.68 0.68 MA 0.71 0.69 0.70 MANE_VU 0.76 0.74 0.75 MD 0.67 0.63 0.65 ME 0.66 0.63 0.64 MI 0.69 0.70 0.69 MN 0.79 0.81 0.80 MO 0.75 0.73 0.74 MS 0.69 0.71 0.70 MT 0.81 0.81 0.81 MW 0.77 0.78 0.77F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-14 Region June '06 July '06 Mean NC 0.69 0.66 0.68 ND 0.78 0.81 0.79 NE 0.81 0.81 0.81 NH 0.46 0.43 0.44 NJ 0.64 0.61 0.63 NM 0.79 0.79 0.79 NV 0.80 0.75 0.77 NY 0.76 0.76 0.76 OH 0.69 0.69 0.69 OK 0.75 0.71 0.73 OR 0.76 0.78 0.77 PA 0.69 0.68 0.69 RI 0.77 0.75 0.76 SC 0.72 0.72 0.72 SD 0.82 0.83 0.82 TN 0.66 0.64 0.65 TX 0.82 0.79 0.81 UT 0.78 0.74 0.76 VA 0.71 0.68 0.69 VISTAS 0.82 0.81 0.81 VT 0.56 0.55 0.56 WA 0.81 0.83 0.82 WI 0.67 0.67 0.67 WRAP 0.88 0.88 0.88 WV 0.61 0.58 0.60 WY 0.80 0.81 0.81

Table 3-14. Wind Index of Agreement for June and July 2006 MM5 by Month and by State and Region in the 12 km Domain.

Region June '06 July '06 Mean ALL 0.89 0.88 0.88 AZ 0.75 0.76 0.75 CO 0.81 0.82 0.81 ID 0.80 0.78 0.79 NM 0.78 0.80 0.79 NV 0.77 0.74 0.75 UT 0.75 0.74 0.75 WY 0.80 0.81 0.81

Table 3-15. Wind Index of Agreement for June and July 2006. Region June '06 July '06 Mean ALL 0.83 0.84 0.83F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-15 Figure 3-1. Regional Planning Organization (RPO) Boundaries.

Figure 3-2 : Spatial Mean Temperature (Deg. C) for June 2006 within the 4 km Domain.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-16 Figure 3-3. Spatial Mean Temperature (Deg. C) for July 2006 within the 4 km Domain

.

Figure 3-4. Spatial Mean Mixing Ratio (g/kg) for June 2006 within the 4 km Domain.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-17 .

Figure 3-5. Spatial Mean Mixing Ratio (g/kg) for July 2006 within the 4 km Domain.

Figure 3-6. Spatial Mean Index of Agreement for June 2006 within the 4 km Domain.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-18 .

Figure 3-7. Spatial Mean Index of Agreement for July 2006 within the 4 km Domain

Figure 3-8. Spatial Mean Wind Direction (deg.) for June 2006 within the 4 km Domain.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-19 Figure 3-9. Vector Mean Wind Speed (m/s) for June 2006 within the 4 km Domain.

Figure 3-10. Spatial Mean Wind Direction (deg.) for July 2006 within the 4 km Domain.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-20 Figure 3-11. Vector Mean Wind Speed (m/s) for July 2006 within the 4 km Domain

.

Figure 3-12. CPC Analyzed Precipitation for June 2006 over the 36 km Domain.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-21 Figure 3-13. MM5 Estimated Precipitation for June 2006 over the 36 km Domain

.

Figure 3-14. CPC Analyzed Precipitation for July 2006 over the 36 km Domain.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-22 Figure 3-15. MM5 Estimated Precipitation for July 2006 over the 36 km Domain

.

Figure 3-16. CPC Analyzed Precipitation for June 2006 over the 12 km Domain

.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-23 Figure 3-17. MM5 Estimated Precipitation for June 2006 over the 12 km Domain.

Figure 3-18. CPC Analyzed Precipitation for July 2006 over the 12 km Domain.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-24 Figure 3-19. MM5 Estimated Precipitation for July 2006 over the 12 km Domain.

Figure 3-20. CPC Analyzed Precipitation for June 2006 over the 4 km Domain.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-25 Figure 3-21. MM5 Estimated Precipitation for June 2006 over the 4 km Domain.

Figure 3-22. CPC Analyzed Precipitation for July 2006 over the 4 km Domain.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 3-26 Figure 3-23. MM5 Estimated Precipitation for July 2006 over the 4 km Domain.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 4-1 

### 4 Upper-Air Meteorological Analysis

To compare the performance of the model alof t, radiosonde comparison plots were prepared using the “Raobplot” program developed by Ma tthew Johnson of the Iowa DNR. Radiosonde data were selected from the Denver upper air site . Radiosonde plots were prepared for each day during June and July of 2006 (when Denver e xperienced its worst ozone episodes). For presentation and specific comparison purposes, plot s are presented herein in a time step of 36 hours during the episodic period of July 20-30, 20 06 starting with 00Z on July 21, 2006. Thus, there are four 00Z soundings on July 20, 23, 26, and 29 and four 12Z soundings on July 21, 24, 27, and 30. No regard to synoptic-scale weather patterns was considered in interpreting these comparisons.

Figures 4-1 through 4-8 present th e Skew T- log p soundings from observations (dark line) and MM5 simulations (red line) for every 36 hours du ring the episodic period of July 20-30, 2006. Thus, the first figure, Figure 4-1 represents the sounding taken at 00Z on July 20 in Denver (which translates to 1700 hours or 5:00 PM local time disregarding daylig ht savings time on July 19). As can be seen, both the temperature and mo isture profiles match reasonably well with the greatest disparities at th e lower levels and at the 200mb hei ght. Comparisons are best above the 550-600 mb height away from influences of the ea rth’s surface. The magnitude of the winds is in reasonable agreement throughout the soundings but the wind directions agree best above about 400mb. Surface wind directions in the first 850 to 600mb levels are more north northeasterly from the MM5 sounding than the northwesterly observations.

Figure 4-2 presents a morning sounding for Denve r, that is, the 12Z sounding (0500 or 5:00 AM local time) on July 21. As can be seen both th e temperature and moisture soundings overall are reproduced well by the MM5 simulations. The MM5 lower level temperature sounding does not account for the depth of the inversion layer as well as the observations and underestimates the amount of moisture at the surface layers. Wi nds throughout the sounding generally agree very well both in magnitude and direction.

Figure 4-3 represents the sounding taken at 00Z (1700 hours or 5:00 PM local time) on July 23 in Denver. As can be seen, both the temperature and moisture profiles match reasonably well with very little disagreement. The observed moisture profile tends to have more variation than the MM5 sounding and is lower in the upper atmosphere. The magnitude of the winds is in reasonable agreement throughout the soundings as are the wind directions except in the 700- 500mb level where MM5 data are more north northeasterly than the north northwesterly observations.

Figure 4-4 presents a morning sounding for Denve r, that is, the 12Z sounding (0500 or 5:00 AM local time) on July 24. As can be seen both th e temperature and moisture soundings overall are reproduced well by the MM5 simulations. The MM5 lower level temperat ure sounding creates a more significant temperature inve rsion layer than the observations but matches the observations quite well above that. MM5 data are slightly less than the observations for moisture at the surface. Winds throughout the sounding gene rally agree very well both in magnitude and direction except for the surface where the MM5 wi nd directions from the northwest vary from the observed west directions.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 4-2 Figure 4-5 represents the sounding taken at 00Z (1700 hours or 5:00 PM local time) on July 26 in Denver. As can be seen, both the temperature and moisture profiles match reasonably well with very little disagreement. The observed moisture profile tends to have more variation than the MM5 sounding and is lower in the upper atmosphere. The MM5 temperature sounding misses the shallow inversion layer detected in the obs ervations. The magnitude of the winds is in reasonable agreement throughout the soundings as are the wind directions except in the 750- 700mb level where the observations are from the east southeast and the MM5 winds are more north northwesterly.

Figure 4-6 presents a morning sounding for Denve r, that is, the 12Z sounding (0500 or 5:00 AM local time) on July 27. As can be seen both th e temperature sounding over all is reproduced well by the MM5 simulations. The MM5 moisture sounding tends to underpredict the moisture throughout most of the sounding. The MM5 lower level temperature soundi ng creates a stronger temperature inversion layer than the observations but matches the observations quite well above that. Winds throughout the sounding generally agr ee very well both in magnitude and direction with a few exceptions at selected sounding levels (~610 and 350mb).

Figure 4-7 represents the sounding taken at 00Z (1700 hours or 5:00 PM local time) on July 29 in Denver. As can be seen, both the temperature and moisture profiles match reasonably well with very little disagreement. Both the observed and MM5 moisture profiles have variation throughout the sounding with them alternating as to which one is higher and lower. The MM5 temperature sounding misses the shallow superadiab atic condition at the surface but matches the remainder of the sounding very well. The magnit ude of the winds is in reasonable agreement throughout the soundings as are th e wind directions except in th e surface to 700mb level where the observations are from the southeast and the MM5 winds are from the south and south southeast.

Figure 4-8 presents a morning sounding for Denve r, that is, the 12Z sounding (0500 or 5:00 AM local time) on July 30. As can be seen both th e temperature sounding over all is reproduced well by the MM5 simulations. Even the strong invers ion layer at the surf ace is reproduced well by the MM5 data. Within this same layer, however, the MM5 moisture sounding is at odds with the observations up to where the inversion layer ceases. Much disparity between the MM5 and observed moisture data takes place from the surface up to about 500mb. Winds throughout the sounding generally agree very well both in magnit ude and direction with the exception of the 400-300mb level where the observati ons are from the south at 400 mb and from the north at 300mb while the MM5 simulation generally ha s them from the west over this layer.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 4-3 Figure 4-1. Radiosonde Sounding Comparison at Denver on 0Z 20 July 2006.

Figure 4-2. Radiosonde Sounding Comparison at Denver on 12Z 21 July 2006

.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 4-4 Figure 4-3. Radiosonde Sounding Comparison at Denver on 0Z 23 July 2006.

Figure 4-4. Radiosonde Sounding Comparison at Denver on 12Z 24 July 2006.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 4-5 Figure 4-5. Radiosonde Sounding Comparison at Denver on 0Z 26 July 2006.

Figure 4-6. Radiosonde Sounding Comparison at Denver on 12Z 27 July 2006.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 4-6 Figure 4-7. Radiosonde Sounding Comparison at Denver on 0Z 29 July 2006

.

Figure 4-8. Radiosonde Sounding Comparison at Denver on 12Z 30 July 2006

.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 5-1 

### 5 Comparison with Other MM5 Simulations

This section presents a comparison of this J une-July 2006 4 km MM5 simulation with other 4 km annual meteorological simulations that have been completed recently by the ENVIRON/Alpine Team. Tables 5-1 through 5-5 present these comparisons on the basis of the temperature bias and error, the mixing ratio bias and error, and the wind index of agreement.

5.1 Comparison to Other 4 km Simulations

Comparisons between the RAQC June-July 2006 MM5 simulation for Colorado and other 4 km simulations were conducted. All available MM5 simulations over r oughly the same domain at a 4 km grid resolution using the same vertical grid definitions as the 4 km grid simulations are compared. The three New Mexico Environmen t Department (NMED) MM5 simulations for 2003, 2004, and 2005 (McNally and Schewe, 2006 and Schewe and Mc Nally, 2006) were generated for the use in mode ling studies centered over the F our Corners area. The CDPHE 2003 (McNally and Schewe, 2007) simulation was conducted over a 4 km domain that was somewhat larger than the State of Colorado. Thus, the spatial coverage of the simulations were somewhat different. The CDPHE 2003 and th e NMED 2003-2005 simulations were annual simulations, but for comparison, only June a nd July simulations were conducted and are presented in this report. The analysis of th ese simulations was performed using the Alpine Geophysics, MAPS analysis packag e (McNally and Tesche, 1994).

The same benchmarks as described in Section 3 were used in this comparison. Recall the purpose of these benchmarks was not to give a passing or failing grade to any one particular meteorological model application, bu t rather to put its results into the context of other models and meteorological data sets. The benchmarks in clude bias and error in temperature and mixing ratio as well the Wind Speed Index of Agreement (IA) between the models and data bases. As a reference the performance benc hmarks are repeated here:

• Temperature bias: <±0.5 K

• Temperature error: <2.0 K

• Mixing ratio bias: <±1.0 g/kg

• Mixing ratio error: <2.0 g/kg

• Wind Speed Index of Agreement (IA): 0.0 = worst, 0.6=acceptable, 1.0 = best

Temperature bias for both this study and the three y ears of NMED data is pr esented in Table 5-1. This RAQC 2006 MM5 application wa s within the range of the te mperature bias benchmark of <±0.5 K with a -0.21 K average over both months and individual month biases of -0.42 and 0.01. When comparing the RAQC 2006 performance to other study simulations, this RAQC 2006 simulation performed as well or better than the others both on a monthly basis as well as an average basis.

Temperature error is presented in Table 5-2. For this RAQC 2006 a pplication of MM5 the temperature error of 1.79 K was within the guide line temperature error of 2.0 K. All other simulations were higher than the guid eline range by a degree or more.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 5-2 Mixing ratio bias over the 4 km simulation domain for the RAQC 2006 MM5 data set is presented in Table 5-3. The domain-wide bi as for this RAQC 2006 MM5 simulation was 0.18 g/kg which is within the acceptability benchmar k of ±1.0 g/kg. While this mean value of the RAQC 2006 data appears to be bette r than other simulations, closer review indicates this may be an artifact of the average of th e June and July monthly values. The June mixing ratio bias was 0.81 and the July bias was -0.45. Both values are still within the benchmark. Performance by other simulations were similar and generally wi thin the benchmark but were all on the positive side of the bias.

Mixing ratio error over the 4 km simulation domain is presented in Table 5-4 The domain-wide error for this RAQC 2006 MM5 simulation was 1.64 g/kg which is less than the benchmark of 2.0 g/kg. The mixing ratio bias was within the range of the acceptability benchmark for both months and compared well in both magnitude and variability to other data sets.

Wind speed index of agreement (IA) is presente d in Table 5-5. The domain-wide IA for the RAQC 2006 simulation was 0.84 which is above the minimally guideline value of 0.6 and tending toward the best agreement level of 1.0. This RAQC 2006 data was comparable to all other data sets.

Table 5-1. Temperature Bias (K) For June and July 4 km MM5 Simulations.

Region Jun Jul Mean RAQC 2006 -0.42 0.01 -0.21 CDPHE 2003 0.73 -0.25 0.24 NMED 2003 0.49 -0.11 0.19 NMED 2004 0.87 0.97 0.92 NMED 2005 0.94 0.58 0.76

Table 5-2. Temperature Error (K) for June and July 4 km MM5 Simulations

. Region Jun Jul Mean RAQC 2006 1.93 1.64 1.79 CDPHE 2003 3.07 3.82 3.45 NMED 2003 3.36 3.70 3.53 NMED 2004 3.51 3.28 3.40 NMED 2005 3.51 3.71 3.61

Table 5-3. Mixing Ratio Bias (g/kg) for June and July 4 km MM5 Simulations

. Region Jun Jul Mean RAQC 2006 0.81 -0.45 0.18 CDPHE 2003 0.30 1.71 1.01 NMED 2003 0.51 1.24 0.88 NMED 2004 0.72 0.62 0.67 NMED 2005 0.52 1.37 0.95F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 5-3 Table 5-4. Mixing Ratio Error (g/kg) for June and July 4 km MM5 Simulations.

Region Jun Jul Mean RAQC 2006 1.60 1.68 1.64 CDPHE 2003 1.36 2.25 1.81 NMED 2003 1.37 1.88 1.63 NMED 2004 1.50 1.73 1.62 NMED 2005 1.49 1.91 1.70

Table 5-5. Wind Index of Agreement for June and July 4 km MM5 Simulation.

Region Jun Jul Mean RAQC 2006 0.83 0.84 0.84 CDPHE 2003 0.83 0.83 0.83 NMED 2003 0.80 0.80 0.80 NMED 2004 0.81 0.81 0.81 NMED 2005 0.80 0.80 0.80F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 6-1 

### 6 References

Baker, Kirk, and M. Johnson, et al. 2005. “Meteorological M odeling Performance Summary for Application to PM2.5/Haze/Ozone Modeling Proj ects”, prepared by the Lake Michigan Air Directors Consortium, Des Plaines, IL.

Dudhia, J., 1993. "A Non-hydrosta tic Version of the Penn Stat e/NCAR Mesoscale Model: Validation Tests and Simulation of an Atlantic Cyclone and Cold Front", Mon. Wea. Rev. , Vol. 121. pp. 1493-1513.

Emery, C. et al., 2001. “Enhanced Meteorological Modeling and Performance Evaluation for Two Texas Ozone Episodes”, prepared for the Texas Natural Resource Conservation Commission, prepared by ENVIRON Inte rnational Corporation, Novato, CA.

Grell, G. A., J. Dudhia, and D. R. Stauffer, 1994. "A Description of the Fifth Generation Penn State/NCAR Mesoscale Mode l (MM5). NCAR Tech. Note, NCAR TN-398-STR, 138 pp.

Kemball-Cook S., Y. Jia, et al. 2005. “Annua l 2002 MM5 Meteorological Modeling to Support Regional Haze Modeling of the Western Unite d States”, Prepared for the Western Regional Air Partnership, pr epared by ENVIRON International Corporation and University of California at Riverside.

McNally, D. E., and G. J. Sc hewe, 2006. “Evaluation of 36/12/4 km MM5 for Calendar Year 2003”, “Evaluation of 36/12/4 km MM5 for Ca lendar Year 2004”, “Evaluation of 36/12/4 km MM5 for Calendar Year 2005”, prepar ed for the New Mexico Environment Department, prepared by Alpine Geophysics, LLC, Arvada, CO.

McNally, D. E., and G. J. Schewe, 2007. “Evalu ation of 36 km MM5 for Calendar Year 2006 Over the continental United States”, prepar ed for the ENSR Corporation, prepared by Alpine Geophysics, LLC, Arvada, CO.

McNally, D. E., and T. W. Tesche, 1994. "MAPS 2.3 User's Guide", Alpine Geophysics, LLC, Golden, CO.

McNally, D. E., and T W. Tesche, 2003. “Annual App lication of MM5 to the Continental United States”, prepared for the U. S. Environm ental Protection Agency, Office of Air Quality Planning and Standards, prepared by Alpine Geophysics, LLC, Arvada, CO.

McNally, D.E. and G.J. Schewe, 2007, “Evalua tion of 4 km MM5 for Calendar Year 2003 over Colorado”, prepared for the Colorado Departme nt of Public Healt h, prepared by Alpine Geophysics, LLC, Arvada, CO.

Olerud Don, and A. Sims, 2004, “MM5 2002 Modeli ng in Support of VISTAS (Visibitility Improvement – State and Tribal Association of the Southeast”, prepared for the VISTAS Technical Analysis Workgroup, prepared by Ba ron Advanced Meteorological Systems, LLC, Raleigh, NC.F:\Denver_O3_2008\Reports\Preliminary_M M5\draft#1\MM5_Eval_DENSIP_Feb25_2008.doc 6-2 Schewe, G. J., and D.E. McNally, 2006, “Evalu ation of 36/12/4 km MM5 for Calendar Year 2005”, prepared for the New Mexico envir onment Department, prepared by alpine Geophysics, LLC, Arvada, CO.