1. Template Simulation of Wintertime High Ozone Concentrations in Southwestern Wyoming Ralph E. Morris, Susan Kemball-Cook, Bonyoung Koo, Till Stoeckenius and Greg Yarwood ENVIRON International Corporation Novato, California 2009 CMAS Conference October 19-21, 2009 Chapel Hill, North Carolina

2. CMAS 2009 2 Increased Demand for Domestic Energy Production Source: Wyoming Oil and Gas Conservation Commission Wyoming Natural Gas Production: 1978-2008

3. CMAS 2009 3 High Ozone in Winter in SW Wyoming In 2005, WDEQ began monitoring in Jonah-Pinedale Area and found high wintertime ozone concentrations Field studies in 2007, 2008 and 2009 Jonah: Feb 3, 2005 Feb 3

4. CMAS 2009 4 Wyoming showing Pinedale and Wind River Range Northeast of Pinedale

5. CMAS 2009 5 SW Wyoming Oil and Gas Development

6. CMAS 2009 6 Monitoring Sites and O&G Wells in SWWY

7. CMAS 2009 7 Southwest Wyoming Jonah Gas Field

8. CMAS 2009 8 Jonah Area in 1986

9. CMAS 2009 9 Jonah Area in 1999

10. CMAS 2009 10 Jonah Area in 2007

11. CMAS 2009 11 Upper Green River Ozone Study Monitoring Sites during 2009 Field Study Mesonet Sites Permanent Sites (except Jonah & Boulder2) HRA Sites

12. CMAS 2009 12 Monitored Monthly Maximum 8-Hour Ozone Upper Green Winter Peaks 20052006200720082009 March

13. CMAS 2009 13 Unique Features of SWWY Ozone Episodes Winter events –Low sun angle –Cold temperatures Snow Cover Rural location Significant oil & gas development

14. CMAS 2009 14 Role of Mixing Heights Elevated O3 when MH < 150 m AGL Note SODAR max range = 250 m agl SODAR Mixing Height Peak 8-Hr Avg O3 at Boulder 2008 Data

15. CMAS 2009 15 UV Radiation and Snow Cover 2 March: Albedo = 0.8 (snow) 23 March: Albedo = 0.06 (bare ground) UGWOS ’07 Data

16. CMAS 2009 16 Effects of Albedo on Photolysis Rates using CMAQ JPROC Program (JPROC default Albedo = 0.05) July 18 January 18 Recall Tyler Cruickshank (UDEQ/DAQ) Talk at 2008 CMAS Conference 0.50 snow Albedo used in Base Case 0.75 SWWY Albedo 6 Factor analysis

17. CMAS 2009 17 2009 Data

18. CMAS 2009 18 CAMx Modeling Domains: 2005 & 2006 MM5/SMOKE 36 km domain provided BCs to 12 km domain 12/4 km domains run with two-way grid nesting

19. CMAS 2009 19 Wintertime Ozone Sensitivity Tests WDEQ field study and analysis show the following six factors are associated with high winter ozone in SWWY: 1.Shallow inversion (limited mixing) 2.White snow on ground (high albedo) 3.Few or no clouds 4.Stagnant and/or recirculating slow surface winds –Large amount of oil & gas development activity producing: 5. High TNMHC concentrations (e.g., ~3,000 ppbC) 6. High TNMHC/NOx Ratios (e.g., ~90:1 at Jonah) Perform initial CAMx base case simulation running the model “out of the box” for the February 2006 high ozone period

20. CMAS 2009 20 CAMx Base Case – Jonah, Feb 18-28, 2006 CAMx Base Case underestimates the February 25-27 peaks by ~30-40 ppb Feb 19Feb 25 Feb 26Feb 27

21. CMAS 2009 21 Account for 6 Factors for Wintertime Ozone 1. Shallow Inversion –Cap MM5 PBL heights in Jonah-Pinedale area on episode days to 100 m AGL 2. White snow on Ground –Spatially varying CAMx snow cover input file developed based on observations –Increase snow Albedo from 0.50 to 0.75 based on field study observations 3. Few or No Clouds –Eliminate MM5 cloud cover

22. CMAS 2009 22 Account for 6 Factors for Wintertime Ozone 4. Stagnant and/or Recirculating Slow Surface Winds –MM5 winds already fairly slow 5. High TNMHC Concentrations (several 1,000s ppbC) 6. High TNMHC:NOx Ratio (~90:1) –Emissions Inventory TNMHC:NOx ratio in Jonah-Pinedale area 13:1 –Field Study 6-9am measured TNMHC:NOx at Jonah averages ~90:1 on high ozone days –Multiply TNMHC emissions in Jonah-Pinedale area by factor of 3 (3xTNMHC)

23. CMAS 2009 23 Winter Ozone 6 Factor Sensitivity Test Results Grey Line = Observed Hourly Ozone Red Line = CAMx Base Case Blue Line = CAMx 6 Factor Sensitivity Test JonahBoulder

24. CMAS 2009 24 Daily Maximum 8-Hour Ozone (ppb) February 27, 2005 Base Case6 Factor Sensitivity Case

25. CMAS 2009 25 6-9am TNMOC Concentrations (ppbC) February 27, 2005 Field Study ~1000s @ Jonah on high ozone days Base Case6 Factor Sensitivity Case JJ

26. CMAS 2009 26 6-9am TNMOC:NOx Ratios February 27, 2005 Field Study ~90:1 @ Jonah on high ozone days Base Case6 Factor Sensitivity Case J J

27. CMAS 2009 27 Winter Ozone Sensitivity Tests Test Effect of Each of the 6 Factors 6 Factor Sensitivity Test –Cap MM5 PBL depths in Jonah/Pinedale at 100 m AGL –Removed MM5 clouds from met inputs –Increase snow Albedo from 0.50 to 0.75 –3xTNMOC emissions in Jonah/Pinedale to better match field study TNMOC concentrations and TNMOC:NOx Ratio Sens#1: Original MM5 PBL Depths Sens#2: Original MM5 PBL Depths and Clouds Sens#3: Original MM5 PBL and Clouds & 0.50 Snow Albedo

28. CMAS 2009 28 February 26, 2005 100 m cap - MM5 PBLNo Clouds - MM5 Clouds 0.75 - 0.50 snow Albedo 3xTNMOC - 1xTNMOC

29. CMAS 2009 29 February 27, 2005 100 m cap - MM5 PBLNo Clouds - MM5 Clouds 0.75 - 0.50 snow Albedo 3xTNMOC - 1xTNMOC

30. CMAS 2009 30 Conclusions Using MM5/CAMx “out-of-the-box” fails to produce high wintertime ozone in SWWY With addition of the “6 Factors” CAMx able to produce high winter ozone events in SWWY Increasing snow Albedo from 0.50 to 0.75 and increases TNMHC emissions 3x most important –0.75 Albedo fully justified from field study –More refined wind modeling and better emissions representation may be able to produce high morning TNMHC concentrations and TNMHC:NOx ratios

31. CMAS 2009 31 Acknowledgements The analysis of the photochemical modeling results would not have been possible without the results of the Wyoming Department of Environmental Quality (WDEQ) Air Quality Division (AQD) field study data and analysis that was conducted by the AQD and their contractors: –ENVIRON –T&B Systems –Meteorological Solutions, Inc. –Argonne National Laboratory SWWY O&G emissions were developed by BP America and Sage Consulting, which has also been integral to this analysis