1. A New Version of CMAQ-MADRID and Comparison with CMAQ Christian Seigneur, Betty Pun, Prakash Karamchandani, Krish Vijayaraghavan, and Shu-Yun Chen AER San Ramon, California Eladio Knipping and Naresh Kumar EPRI Palo Alto, California

2. CMAQ-MADRID CMAQ-MADRID 1 –operational version (e.g., BRAVO) CMAQ-MADRID 2 –research-grade version Both versions currently available from CMAS

3. CMAQ-MADRID 1 vs. CMAQ CMAQ-MADRID Sectional representation of PM 14 SOA precursors Heterogeneous reactions CMAQ Modal representation of PM 6 SOA precursors No explicit heterogeneous reactions

4. CMAQ-MADRID 1 Computational Assessment Total CPU time = 26.3 ms grid cell -1 hr -1 AMD Athlon MP 2100+ July 2002 version

5. CMAQ Improvement in Transport Calculations July 2002 version September 2003 version Total CPU time = 7.9 ms grid cell -1 hr -1 AMD Athlon MP 2100+ Total CPU time = 2.2 ms grid cell -1 hr -1 AMD Athlon MP 2100+

6. Improvements in CMAQ-MADRID Computations CMAQ 2003 version 4.3 Reduction of the number of explicit SOA precursors from 14 to 8 Gain in CPU time of about one order of magnitude CMAQ-MADRID 1 is currently within 10% of CMAQ

7. New Treatment of SOA in CMAQ-MADRID 1 Anthropogenic precursors: no changes Toluene Xylenes

8. New Treatment of SOA in CMAQ-MADRID 1 Biogenic precursors: 12 6 Approach for optimization: Retain the precursors with significant emissions Group species according to precursor reactivity and SOA properties (molecular weight, structure & volatility)

9. New Treatment of SOA in CMAQ-MADRID 1  -PineneAPIN  -Pinene,  3 -carene & sabineneBPIN LimoneneLIM TerpineneTER Ocimene, linalool, terpineol & terpinolene OCI Humulene & caryophylleneHUM

10. Example Simulation: CENRAP Regional Haze - Preliminary Base case One-month simulation: July 2002 Central and eastern United States MM5 simulation by CENRAP SMOKE emissions by UNC (modified for CMAQ-MADRID by AER)

11. PM 2.5 (  g/m 3 )

12. Sulfate (  g/m 3 )

13. Nitrate (  g/m 3 )

14. OM (  g/m 3 )

15. SOA (  g/m 3 )

16. Chemical Composition at Big Bend National Park, TX Observation 6.2  g/m 3 CMAQ MADRID 1 3.3  g/m 3 CMAQ original 2.5  g/m 3

17. Chemical Composition at Upper Buffalo Wilderness Area, AK Observation 13.9  g/m 3 CMAQ MADRID 1 11.2  g/m 3 CMAQ original 8.5  g/m 3

18. Chemical Composition at Voyageurs National Park, MN Observation 7.2  g/m 3 CMAQ Madrid1 6.8  g/m 3 CMAQ original 4.9  g/m 3

19. Conclusion CMAQ-MADRID 1 is now comparable in computational speed to CMAQ CMAQ-MADRID 1 has a more detailed representation of biogenic SOA and leads to more SOA formation than CMAQ

20. Next Steps Incorporation of MADRID 1 and MADRID 2 into the forthcoming version of CMAQ (2004) Transfer of CMAQ-MADRID 2004 to CMAS

21. Acknowledgements We are grateful to CENRAP for the use of the July 2002 model inputs