1. Models-3 Users’ Workshop 2003 Research Triangle Park, NC Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division 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. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Outline Summary of the NE-OPS 1999 study Applications of and evaluation of CMAQ and CAMx Discussions and future work

3. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC 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. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Nested Modeling Domain

5. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Monitor Stations and NE-OPS Flight Tracks

6. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC 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. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC NOx and VOC Emissions

8. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Model Configuration CMAQCAMx AdvectionBott schemeSmolarkiewicz scheme TurbulenceK-theory based eddy formulation ChemistryRADM2 or CB4CB4 mechanism with updated isoprene chemistry Number of gas-phase chemical species 59 (RADM2); 36 (CB4) 25 Number of chemical reactions 157 (RADM2); 93 (CB4) 96

9. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Run Time Comparison CMAQCAMx Nesting1-way nesting2-way nesting Type of machine used Sun Fire 280R with dual 750 Hz UltraSPARC-III CPU and 4GB memory Linux PC with single AMD Athlon XP 1800 and 1GB memory Run Time3-4 hours per model day for each grid About 0.5 hour per model day for the 3-level nested grid

10. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Daily maxima of ground level ozone for 7/18/1999 CMAQ CAMx AirNow

11. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Daily maxima of ground level ozone for 7/19/1999 CMAQ CAMx AirNow

12. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Daily maxima of ground level ozone for 7/20/1999 CMAQ CAMx AirNow

13. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Space-time paired comparisons of ground level ozone with observation CMAQ CAMx

14. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Quantile-quantile comparisons of ground level ozone with observation CMAQ CAMx

15. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Model-to-model comparison

16. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Ozone Time Series Comparison between Model Predictions and Observations at Middlesex, NJ

17. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Ozone Time Series Comparison between Model Predictions and Observations at Philadelphia

18. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Selected NEOPS Flights

19. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Comparison with flight measurements (I)

20. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC Comparison with flight measurements (II)

21. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC 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. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC 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. Computational Chemodynamics Laboratory EOHSI - Exposure Measurement & Assessment Division Models-3 Users’ Workshop 2003 Research Triangle Park, NC 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)