1. 1 Air Quality during the Sept. 2013 Houston DISCOVER-AQ Deployment and Preliminary Evaluation of NOAA CMAQ Air Quality Forecasts Kenneth Pickering, NASA GSFC Bryan Duncan, NASA GSFC Pius Lee, NOAA ARL Mariel Friberg, Georgia Tech James Crawford, NASA LaRC and the DISCOVER-AQ Observation Team 6 th Biannual AQAST Meeting – Rice University – January 15, 2014

2. 2 Outline 1)Overview of meteorological and air quality conditions during the Houston DISCOVER-AQ experiment 2)Significant pollution episodes – aerosols and ozone 3)Air quality model forecasts available during Houston deployment 2)Preliminary evaluation of NOAA CMAQ forecasts using DISCOVER-AQ P-3B aircraft data

3. Daily 1-Hour Max Ozone (ppbv) – All Stations September 1 st – 30 th #1 #2 #3 #4#5 #6 #7 #8 #9 Relatively clean3 flight days Moderate pollution4 Strongly polluted2 < > clouds, heavy rains, marine air bay, sea breezes following cold front

4. Daily 8-Hour Max Ozone (ppbv) September 1 st – 30 th NAAQS: 75 ppbv 8-hr avg Sites exceeding NAAQS 8 3

5. Conroe Jones Forest Texas City La Porte Seabrook Air Monitoring Sites in Houston Region

6. 1-Hour Ozone (ppbv) September 25 th – 26 th 25th26th La Porte Seabrook Texas City Jones Forest Conroe La Porte

7. Hourly PM 2.5 September 2 nd – 26 th Hourly PM 2.5 (ug/m 3 ) 20 10 30 #1 #2 #3#4 #5 #6 #7 #8 #9 NAAQS: 35 µg/m 3 24-hr avg.

8. 8 High AOD associated with agricultural fire plumes from Mississippi Valley. Back door cold front pushed smoke over Houston. No real impact seen in surface PM2.5. Houston Aerosol Episode of Sept. 14, 2013 Hourly PM2.5 (µg/m 3 )

9. Houston Aerosol Episode of September 14, 2013 HSRL-2 Extinction West Houston to Smith Point P-3B Nephelometer & Absorption Photometer West Houston

10. GEOS-5 aerosol forecast from 00 UT 14 Sept. Cloud cover Extinction AOD GEOS-5 global model at 0.25 deg. resolution; GOCART aerosols, CO, SO 2 ; includes assimilation of MODIS AOD Run by Arlindo da Silva at NASA/GSFC

11. 11 Univ. of Houston (Yunsoo Choi) WRF/CMAQ - 4-km resolution; NEI-2008 with MOVES WRF-Chem – 4-km resolution; NEI-2005 NOAA/ARL (Pius Lee) WRF/CMAQ at 12-km resolution; point and area emissions projected to current year; MOBILE6 vehicle emissions TCEQ (Mark Estes and ENVIRON) WRF/CAMx at 12-km resolution Regional Air Quality Forecasts for Houston Deployment

12. NOAA Experimental CMAQ CTM CMAQ v. 4.6 Driven by WRF-NMM meteorology Intervals48 hour forecasts from 06Z Chemical mechanismCB05 Aerosol moduleAero4 Emissions Anthropogenic: NEI-05; pt. & area sources projected to 2013 Biogenic: BEIS-3 Domain12 km horizontal resolution Vertical coordinateNMM Hybrid (60L) Radiation / PhotolysisLacis-Hansen Bulk PBLMellor-Yamada-Janjic (MYJ) local TKE CloudsFerrier cloud water, graupel/ice Convective cloud mixingBetts-Miller-Janjic Mass Adjustment Land surfaceNOAH LSM

13. Galveston Smith Point Channelview Deer Park Moody Tower West Houston Conroe Manvel Croix 9/25 9/26

14. GV SP MT WH CR CV DP MC GV SP MT WH CR CV DP MC GV SP MT WH CR CV DP MC Gulf Galv Bay CMAQ got the right idea of high ozone over Galveston Bay area late in the day, but failed to capture the early onset (by 12 – 1 PM) of the bay breeze and the magnitude of the effect on ozone. 12-km resolution insufficient to resolve bay breeze. CMAQ maximum ozone over Gulf not found.

15. Conroe Galveston

16. GV SP MT WH CR CV DP MC GV SP MT WH CR CV DP MC NW CR m/a CMAQ very well predicted the ozone plume to the NNW of Houston during the afternoon

17. Conroe Galveston CMAQ missed elevated O 3 layer Conroe profile well forecast O 3 maximum to NNW of Houston well forecast

18. 18 Summary The DISCOVER-AQ Houston campaign completed successful flights with both P-3B and King Air on nine days during Sept. 2013. Much of the month characterized by low to moderate ozone. Two days (Sept. 25 and 26) with high ozone in parts of the region, following cold frontal passage. One day with enhanced AOD as a result of agricultural fires in the Miss. Valley, but surface PM2.5 little affected. NOAA CMAQ ozone forecast underestimated observations on Sept. 25 due to inability to resolve bay/sea breeze. Performed well on Sept. 26. Forthcoming work: -More comprehensive NOAA CMAQ forecast evaluation -Retrospective fine-resolution CMAQ and WRF-Chem simulations -Statistical analysis of surface versus column observations