Evaluating Ozone Predictions from Photochemical Models Using NE-OPS 1999 Observations

1. Evaluating Ozone Predictions from Photochemical Models Using NE-OPS 1999 Observations Qing Sun, Anatharaman Chandrasekar, Panos G. Georgopoulos Environmental and Occupational Health Sciences Institute, a joint project of UMDNJ — R. W. Johnson Medical School and Rutgers University 170 Frelinghuysen Road, Piscataway, New Jersey 08854 C. Russell Philbrick Penn State University, Department of Electrical Engineering and Applied Research Laboratory, University Park, Pennsylvania Bruce Doddridge University of Maryland, Department of Meteorology, College Park, Maryland One Atmosphere, One Community, One Modeling System: Models-3 Users’ Workshop October 27-29, 2003 Research Triangle Park, North Carolina

2. Outline • Summary of the NE-OPS 1999 study • Applications of and evaluation of CMAQ and CAMx • Discussions and future work

3. Summary of the NE-OPS Study • North East - Oxidant and Particle Study (NE-OPS), sponsored by EPA • Objectives: • Determine conditions leading to high O3 and PM • Local vs distant sources • Roles of meteorological properties • Participants: Penn State, Millersville, Harvard SPH, Univ Maryland, SUNY at Albany, Rutgers, Brookhaven Nat Lab, PNNL, etc • Location: centered at the Baxter water treatment plant in north Philadelphia • Time span: 1999 – 2001 (this study uses data from July 11-25, 1999) • Included both meteorological and air quality measurements • Measurements approaches: instrumented airplanes; Radar wind profiler/RASS sounder; Lidar atmospheric profile sensor; tethered balloons; ozonesondes, rawinsondes, and ground based measurements of PM compositions.

4. Nested Modeling Domain

5. Monitor Stations and NE-OPS Flight Tracks

6. Problem specifications • Modeling period: 7/11/1999 to 7/25/1999 • Three levels of nested grids (36km, 12km and 4km) • Grid dimensions: 72×60, 69×54 and 63×72 • 14 Layers for CMAQ, 8 for CAMx • Meteorology prepared with MM5 • Emissions prepared from USEPA’s 1998 NET inventory, using SMOKE

7. NOx and VOC Emissions

8. Model Configuration

9. Run Time Comparison

10. Daily maxima of ground level ozone for 7/18/1999 CMAQ AirNow CAMx

11. Daily maxima of ground level ozone for 7/19/1999 CMAQ AirNow CAMx

12. Daily maxima of ground level ozone for 7/20/1999 CMAQ AirNow CAMx

13. Space-time paired comparisons of ground level ozone with observation CMAQ CAMx

14. Quantile-quantile comparisons of ground level ozone with observation CMAQ CAMx

15. Model-to-model comparison

16. Ozone Time Series Comparison between Model Predictions and Observations at Middlesex, NJ

17. Ozone Time Series Comparison between Model Predictions and Observations at Philadelphia

18. Selected NEOPS Flights

19. Comparison with flight measurements (I)

20. Comparison with flight measurements (II)

21. Conclusions • The two models, CMAQ and CAMx, predicted similar general patterns of pollutant spatial and temporal distributions • There is considerable discrepancy of predictions by the two models for surface ozone: • CAMx significantly over-predicting ozone peaks for certain days during the high ozone hours • CAMx predicts close-to-zero ozone during the nights, probably reflecting the failure of the model to sufficiently account for the effects of an upper layer ozone reservoir accumulated during the daytime hours for the high ozone days

22. On-going and future work • Parallel processing on Linux cluster • Emissions from 1999 and projected 2001(?) NEI • Seasonal or annual runs of CMAQ and CAMx • Linking the annual air quality applications with MENTOR/SHEDS for exposure/dose analyses MENTOR – Modeling Environment for Total Risk SHEDS – Stochastic Human Exposure and Dose Simulation

23. Acknowledgements • State of New Jersey Department of Environmental Protection (NJDEP) funded Ozone Research Center (ORC) • U.S. EPA Center for Exposure and Risk Modeling (CERM) (EPAR-827033) • U.S. EPA funded NorthEast Oxidant and Particle Study (NE-OPS) (EPA-TPSU-UMDNJ-826373-14)