2. Annual Simulations of Models-3/CMAQ: Issues and Lessons Learned Pat Dolwick, Carey Jang, Norm Possiel, Brian Timin, Joe Tikvart Air Quality Modeling Group USEPA/OAQPS/EMAD Research Triangle Park, North Carolina M3 User Workshop, 10/21/2002

3. OUTLINE b b Applications and evaluations of Models-3/CMAQ at USEPA/OAQPS b b Issues related to annual modeling of ozone and PM b b Preliminary comparison results between CMAQ-2002 and -2001 releases b b On-going and upcoming activities

4. Models-3/CMAQ Applications and Evaluations at EPA/OAQPS b Western U.S. Application Episodic O 3, July 96, 36/12 km, evaluation, (AWMA 2001) b Annual Continental U.S. Application 1-atmosphere, annual 1996, 36-km, evaluation & diagnostics, on-going for 2001, (AWMA 2001 & 2002) b Eastern U.S. Application 1-atmosphere, July 95, urban applications, 36/12/4-km, emissions control & growth (on-going) b Intercontinental Transport modeling Trans-Oceanic transport of air pollutants and nested U.S. & Asia/China modeling for year 2001

5. 12 km western US ozone domain 36 km western US ozone domain 36 km eastern US domain Models-3/CMAQ Modeling: Domain Maps 36 km Annual National US domain 12 km domain 4 km domain

6. Annual Continental U.S. Application b Features : Annual CMAQ modeling over the continental U.S., “One-Atmosphere” b Model Setup : Annual PM and O 3 (1996) 36-km, 8/12 vertical layers Meteorology : MM5 Emissions Processing: SMOKE Model Evaluation: Compared against observed data (IMPROVE & CASTNET) & REMSAD Papers published in AWMA (2001 & 2002)

8. July 1, 1996 NOx EmissionsSO 2 Emissions

9. Run Time & Disk Space Requirement for Annual CMAQ Simulation b CMAQ annual run time was ~14 days 4 CPUs (400 MHz) Sun Workstations (Enterprise 450); Running 4 quarters of the year concurrently4 CPUs (400 MHz) Sun Workstations (Enterprise 450); Running 4 quarters of the year concurrently ~4 hours/model day (8 layers)~4 hours/model day (8 layers) b Model-Ready Inputs/Outputs (entire year) Emission (SMOKE/ECIP) : 40 GBEmission (SMOKE/ECIP) : 40 GB Meteorology (MM5/MCIP) : 100 GBMeteorology (MM5/MCIP) : 100 GB Outputs (M3/CMAQ) : 250 GB, compressed to 9 GBOutputs (M3/CMAQ) : 250 GB, compressed to 9 GB b The model runs >4 times faster on new Linux PCs 1.6GHz AMD Athlon MP (single CPU)1.6GHz AMD Athlon MP (single CPU) b Current modeling are transitioned to Linux PCs (parallel processing on the PC/Linux cluster is being investigated)

10. 144 127 194 132 126 119 134 13976 56 107 113 149 62 137 215 131 99 Annual Continental U.S. CMAQ Modeling: O 3 (July Max in ppb, 1996)

11. 26 19 26 24 24 22 16 22 24 26 14 14 10 15 18 9 16 9 23 11 12 Annual CMAQ Modeling: Visibility (January Average in Deciview)

12. Annual CMAQ Modeling: Wet Deposition Sulfur Wet Deposition Nitrogen Wet Deposition (January average)

13. Models-3/CMAQ Simulation: Annual Average PM 2.5Sulfate PM Organic PM Nitrate PM

14. Observation (IMPROVE) Model Annual Average: Total PM 2.5 mass

15. Observation Model NO 3 SO 4 OC Annual Average: PM 2.5 Species (SO 4, NO 3, OC)

16. Models-3/CMAQ : Monthly Average (July) PM 2.5 Sulfate PM Organic PM Nitrate PM

17. Observation Model NO 3 SO 4 OC Summer Average: PM 2.5 Species (SO4, NO3, OC)

18. Models-3/CMAQ : Monthly Average (January) PM 2.5 Sulfate PM Organic PM Nitrate PM

19. Winter Average: PM 2.5 Species (SO4, NO3, OC) Observation Model NO 3 SO 4 OC

20. Annual CMAQ Modeling: CB4 vs. RADM2 Nitrate PM (January avg, 1996)

21. Annual CMAQ Modeling: CB4 vs. RADM2 Sulfate PM (July avg, 1996)

22. NH 3 Sensitivity Modeling Base 50% NH 3 reduction 1.16 0.62 1.24 0.53 0.70 0.08 1.69 0.09 Nitrate PM : (January Avg, 1996)

23. On-going and Upcoming Modeling Activities at OAQPS/AQMG b Continue model evaluation and sensitivity test for the annual 1996 continental US run Examine nitrate and organic PM issues – –Emissions issues (NH 3, BEIS3, Fire, CA emis. etc.) – –Vertical layer sensitivity (8-14 layers) – –Nitrate nighttime chemistry issue – –“N2O5 + H2O --> 2HNO3” and “NO2 + OH --> HNO3” – –Dry deposition Issue – –Vertical diffusion sensitivity

24. b Modeling support for regulatory analysis ! ! Clear Skies Initiative (on-going) ! ! PM Transport Rule (2002/03) ! ! Nonroad Rule (2002/03) ! ! Section 812 CAAA Prospective Update (2003) ! ! 8-Hour Ozone Implementation Guidance (2002/03) ! ! PM NAAQS Review (2003) ! ! Regional Haze Rule (on-going) On-going and Upcoming Modeling Activities at OAQPS/AQMG (contd.)

25. b Improvement of base model simulation Increase vertical resolution (from 8 to 12 layers) Monthly NH 3 emissions adjustments from animal husbandry & fertilizer operations (based on ORD inverse modeling) BEIS-3/BELD-3 NOx emissions from new Nonroad model California NOx & VOC emission adjustments Updated plume rise algorithm in SMOKE Upgrade to latest Models-3/CMAQ release (July 2002) On-going and Upcoming Modeling Activities at OAQPS/AQMG (contd.)

26. National 1996 CMAQ Modeling: Peak Ozone (July 1996) 8-layer CMAQ 12-layer CMAQ Old Base vs. New Base

27. Sulfate PM (Monthly average, July 1996) 8-layer CMAQ 12-layer CMAQ Annual CMAQ Modeling: Old Base vs. New Base

28. Nitrate PM (Monthly average, January 1996) 8-layer CMAQ 12-layer CMAQ Annual CMAQ Modeling: Old Base vs. New Base

29. Anthropogenic SOA Biogenic SOA (BEIS2 vs. BEIS3) 8-layer CMAQ 12-layer CMAQ Organic PM (July 1996) Annual CMAQ Modeling: Old Base vs. New Base

30. CMAQ Seasonal Ozone (8-hr max) Evaluation Spring Fall Summer Winter Observation Model

31. CMAQ Seasonal Sulfate PM Evaluation Spring Fall Summer Winter Observation Model

32. CMAQ Seasonal Organic PM Evaluation Spring Fall Summer Winter Observation Model

33. CMAQ Seasonal Nitrate PM Evaluation Spring Fall Summer Winter Observation Model

34. CMAQ Seasonal Total NO 3 (HNO3 + Nitrate PM) Evaluation Spring Fall Summer Winter Observation Model

35. CMAQ vs. IMPROVE Model performance : Annual average

36. CB-IV SAPRC-99 CB-IV SAPRC-99 (January Average) Nitrate Nighttime Chemistry Sensitivity “N2O5  HNO3” rxn rate (sensitivity test)

37. Base Kv (min) = 5 Base Kv (min) = 5 Kv(min) = 1, Stable up to 3 rd layer, ~230 m Kv(min) = 1, Stable up to 3 rd layer, ~230 m (January Average) Kv (vertical diffusion) Sensitivity

38. (January 19, 2002) NH 3 Dry Deposition Issue in CMAQ NH 3 Dry Dep. (V d ) Air Temp. NH 3 Dry Dep. (V d ) Air Temp.

39. b Improvement of base model simulation Increase vertical resolution (from 8 to 12 layers) Monthly NH 3 emissions adjustments from animal husbandry & fertilizer operations (based on ORD inverse modeling) BEIS-3/BELD-3 NOx emissions from new Nonroad model California NOx & VOC emission adjustments Updated plume rise algorithm in SMOKE Upgrade to latest Models-3/CMAQ release (July 2002) – –Computer time issue (runtime doubled) – –Nitrate PM overprediction issue – –Organic PM/Biogenic SOA issue On-going and Upcoming Modeling Activities at OAQPS/AQMG (contd.)

40. (January avg.) Difference (CMAQ/2002 – CMAQ/2001)  PM 2.5  PM 2.5  Nitrate PM

41. (January avg.) Nitrate PM CMAQ-2001 (AE2) CMAQ-2002 (AE3) CMAQ-2001 (AE2) CMAQ-2002 (AE3)

42. (July avg.) Difference (CMAQ/2002 – CMAQ/2001)  PM 2.5  PM 2.5  Biogenic SOA

43. CMAQ- 2002 (AE3) CMAQ- 2001 (AE2) Anthropogenic SOA Biogenic SOA (July avg.) 2 ug/m3 6 ug/m3

44. b Annual National CMAQ run for year 2001 2001 MM5 & NEI emissions thru SMOKE Model evaluation against expanded PM speciation network (TREND, IMPROVE, etc.) b “Intercontinental Transport of Climatic Effect of Air Pollutants” (ICAP) Project Modeling of trans-oceanic pollutant transport Nested modeling over East Asia/China Region Upcoming Modeling Activities at OAQPS/AQMG

45. “Intercontinental Transport and Climatic Effects of Air Pollutants (ICAP)” : USEPA Modeling Initiative NASA/MOPPIT: CO Transport

46. Intercontinental Transport and Climatic Effects of Air Pollutants (ICAP)

47. Air Quality Modeling over China : Ozone

48. PM 2.5Sulfate PM Organic PM Nitrate PM Air Quality Modeling over China : PM

49. Visibility (Deciview) Sulfate Wet Deposition Air Quality Modeling over China

50. b b PM 2.5 modeling more complex than O 3 modeling Multi-species vs. single species SO 2, NOx, VOC, or NH 3 -limited vs. VOC or NOx-limted Annual vs. summer pollutants Day + nighttime chemistry vs. daytime chemistry “Gas + aqueous + aerosol” chemistry vs. gas chemistry Organic PM modeling is still a research issue Emission (e.g. NH 3, fire, Biogenic ) & monitoring issues (e.g., OC/EC, nitrate) and provide further modeling challenge b b O 3 and PM are highly linked, “one-atmosphere” modeling is necessary Take Home Message

51. Nitrate PM Sulfate PM -- (decrease) -- (decrease) -- (decrease) -- (decrease) (July Average, 1996) 50% NOx reduction

52. Formation of Secondary PM (PM 2.5 ): Sulfate PM formation: H 2 SO 4 + 2 NH 3 ---> (NH 4 ) 2 SO 4 (s) Gas Phase: O 2,H 2 O SO 2 + OH ---> H 2 SO 4 Aqueous Phase: H 2 O S(IV) + H 2 O 2 ---> H 2 SO 4 (Dominate over low pH) S(IV) + O 3 ---> H 2 SO 4 Nitrate PM formation: HNO 3 + NH 3 NH 4 NO 3 (aq,s) Gas Phase : (daytime) NO 2 + OH ---> HNO 3 Gas &Aq Phase : (nighttime) N 2 O 5 + H 2 O ---> HNO 3 Organic PM formation: (Gas-Particle conversion) VOC + OH ---> SOA O 3, NO 3 (semi-volatile) (Long-chain VOC, Aromatics, Biogenic VOC)

53. Ozone Sulfate PM Ozone Sulfate PM -- (decrease) -- (decrease) -- (decrease) -- (decrease) (July Average, 1996) 50% NOx reduction

54. Ozone Organic PM Ozone Organic PM -- (decrease) -- (decrease) -- (decrease) -- (decrease) (July Average, 1996) 50% NOx reduction

55. Nitrate PM Sulfate PM -- (decrease) + (increase) -- (decrease) + (increase) (January Average) 50% NOx reduction

56. Ozone Sulfate PM Ozone Sulfate PM + (increase) + (increase) + (increase) + (increase) (January Average) 50% NOx reduction

57. Air Toxics Ozone Acid Rain Visibility PM 2.5 WaterQuality. OH. OH Role in Linking Pollutants Formation : One-Atmosphere NOx + VOC + OH + hv ---> O 3 SOx [or NOx] + NH 3 + OH ---> (NH 4 ) 2 SO 4 [or NH 4 NO 3 ] SO 2 + OH ---> H 2 SO 4 NO 2 + OH ---> HNO 3 VOC + OH ---> Orgainic PM OH Air Toxics (POM, PAH, Hg (II), etc.) Fine PM (Nitrate, Sulfate, Organic PM) NOx + SOx + OH (Lake Acidification, Eutrophication)