Alaskan and Canadian forest fires exacerbate ozone pollution over Houston, Texas, on 19 and 20 July 2004

Authors

Gary A. Morris, Department of Physics and Astronomy, Valparaiso UniversityFollow
Scott Hersey, Sid Richardson College, Rice University
Anne M. Thompson, Pennsylvania State University
Steven Pawson, Global Modeling and Assimilation Office, NASA Goddard Space Flight Center
J. Eric Nielsen, Global Modeling and Assimilation Office, NASA Goddard Space Flight Center
Peter R. Colarco, Atmospheric Chemistry and Dynamics Branch, NASA Goddard Space Flight Center
W. Wallace McMillan, Department of Physics, University of Maryland, Baltimore County
Andreas Stohl, Department of Regional and Global Pollution Issues, Norwegian Institute for Air Research
Solene Turquety, Department of Earth and Planetary Sciences, Harvard University
Juying Warner, Joint Center for Earth Systems Technology, University of Maryland, Baltimore County
Bryan J. Johnson, NOAA - ESRL
Tom L. Kucsera, Atmospheric Chemistry and Dynamics Branch, Laboratory for Atmospheres, NASA Goddard Space Flight Center
David E. Larko, Atmospheric Chemistry and Dynamics Branch, Laboratory for Atmospheres, NASA Goddard Space Flight Center
Samuel Oltmans, NOAA - ESRL
Jacquie Witte, Atmospheric Chemistry & Dynamics Branch, NASA Goddard Space Flight Center

Document Type

Article

Publication Date

9-26-2006

Abstract

On Monday, 19 July, and Tuesday, 20 July 2004, the air over Houston, Texas,
appeared abnormally hazy. Transport model results and data from the Atmospheric Infrared Sounder (AIRS), the Moderate Resolution Imaging Spectrometer (MODIS), the Measurement of Ozone by Airbus In-service airCraft (MOZAIC) experiment, and the Total Ozone Mapping Spectrometer (TOMS) indicate that an air mass originating on 12 July 2004 over forest fires in eastern Alaska and western Canada arrived in Houston about 1 week later. Ozonesonde data from Houston on 19 and 20 July show elevated ozone at the surface (>125 ppbv) and even higher concentrations aloft (~150 ppbv
of ozone found 2 km above the surface) as compared to more typical profiles. Integrated ozone columns from the surface to 5 km increased from 17–22 DU (measured in the absence of the polluted air mass) to 34–36 DU on 19 and 20 July. The average on 20 July 2004 of the 8-hour maximum ozone values recorded by surface monitors across the Houston area was the highest of any July day during the 2001–2005 period. The combination of the ozone observations, satellite data, and model results implicates the biomass burning effluence originating in Alaska and Canada a week earlier in exacerbating pollution levels seen in Houston.

Recommended Citation

Morris, G. A., et al. (2006), Alaskan and Canadian forest fires exacerbate ozone pollution over Houston, Texas, on 19 and 20 July 2004, J. Geophys. Res., 111, D24S03, doi:10.1029/2006JD007090.