1. National Aeronautics and Space Administration www.nasa.gov 89th AMS Annual Meeting January 15, 2009 11th Conference on Atmospheric Chemistry Session 10: Air pollution in mega cities in the world DEVELOP National Program NASA Langley Research Center An Assessment of Air Quality in the Houston region: Investigating the ability to infer surface PM 2.5 from remote sensing measurements and examining possible aerosol sources

2. National Aeronautics and Space Administration www.nasa.gov Principal Investigators: Rebecca Legatt – University of Alaska - Fairbanks Amy Sanders – The Pennsylvania State University Erin Roberts – Embry-Riddle Aeronautical University Laura Lynaugh – University of Virginia Derek Doddridge – Tabb High School Brianna Baxley – Grafton High School Science Advisor: Richard A. Ferrare, Ph.D. - NASA Langley Research Center DEVELOP National Program NASA Langley Research Center

3. National Aeronautics and Space Administration www.nasa.gov Outline Community Concerns Objectives Phase One: verification and validation Phase Two: aerosol events and sources Conclusions Future Work

4. National Aeronautics and Space Administration www.nasa.gov Community Concerns High PM 2.5 (particulate matter) concentrations in the Houston area –Associated health risks Sources of PM 2.5 in Houston region Air Quality

5. National Aeronautics and Space Administration www.nasa.gov Objectives Improve analysis methods for forecasting surface PM 2.5 concentrations in the Houston area –Investigate ground-truth of satellite observations –Analyze peak aerosol events –Research PM 2.5 aerosol sources

6. National Aeronautics and Space Administration www.nasa.gov Phase One Outline Show that AOD values can be highly variable –Displayed through Aqua/Terra images Prove that ground-truth can be improved through several methods –Changing size of interest region –Including planetary boundary layer (PBL) height

7. National Aeronautics and Space Administration www.nasa.gov Phase One Compared Aqua and Terra AOD –High correlation analysis: Sept. 13 th, 2006 Ground-truth analysis of Terra AOD with surface PM2.5 –Verified with available High Spectral Resolution Lidar (HSRL) measurements from Aug. – Sept. 2006

8. National Aeronautics and Space Administration www.nasa.gov Phase One Results Terra vs. Aqua AOD visualizations Houston

9. National Aeronautics and Space Administration www.nasa.gov Phase One Results

10. National Aeronautics and Space Administration www.nasa.gov Phase One Further research to find a stronger correlation between surface and satellite measurements –Decreased the size of interest region –Modeled J. Al Saadi’s study and divided by the planetary boundary layer (PBL) height

11. National Aeronautics and Space Administration www.nasa.gov Phase One Results Houston Longitude Region of Interest Latitude Surface Stations within 8 miles R 2 on high aerosol day Terra AOD vs. PM 2.5.7191 Terra AOD/ PBL vs. PM 2.5.8075

12. National Aeronautics and Space Administration www.nasa.gov Phase Two Outline Several sources of AOD in Houston region –Local Sources –Foreign Sources Many tools combined can backtrack possible AOD sources –Aqua/Terra visualization –HYSPLIT model –CALIPSO curtain plot

13. National Aeronautics and Space Administration DEVELOP National Program http://develop.larc.nasa.gov 13 Phase Two Visualized AOD with Terra satellite image –High AOD values on Aug. 28 th, 2006 Utilized HYSPLIT to provide possible back trajectories to emission sources Verified high AOD values with CALIPSO curtain plot –Dust signature supported Saharan dust arrival on Aug. 28 th, 2006.

14. National Aeronautics and Space Administration www.nasa.gov Phase Two Results August 28, 2006 Terra AOD 10:30 A.M. Latitude Houston

15. National Aeronautics and Space Administration www.nasa.gov Phase Two Results

16. National Aeronautics and Space Administration www.nasa.gov Phase Two Results

17. National Aeronautics and Space Administration www.nasa.gov Phase Two Results

18. National Aeronautics and Space Administration www.nasa.gov Phase Two Results Aug 27 8 UTC

19. National Aeronautics and Space Administration DEVELOP National Program http://develop.larc.nasa.gov HYSPLIT initialization Points CALIPSO track Possible dust 19 August 28, 2006 Terra AOD 10:30 A.M. Latitude Longitude Aug 27 8 UTC Houston Phase Two Results

20. National Aeronautics and Space Administration www.nasa.gov Conclusions AOD values can change relatively quickly –3 hour time difference between Terra and Aqua showed large variance –Could be weather-related Low PM 2.5 /AOD correlation can be improved –Decrease region of interest –Divide by PBL height Utilizing multiple tools can provide back trajectories for AOD sources

21. National Aeronautics and Space Administration www.nasa.gov Future Work Investigate local mesoscale and microscale meteorological features Look into horizontal and temporal aerosol variability Study ozone concentrations in the region Focus in on specific emission sites

22. National Aeronautics and Space Administration www.nasa.gov Future Work Provide legislators with information to make informed decisions concerning air quality for the Houston region and beyond