April 24, 2012
Fires cause raised AOD in western Texas. Moves to ozone-filled Houston for Code Orange.
The first image below, courtesy NOAA HMS, shows the fire locations across the United States. The red dots correspond to active fires, and the grey areas are plumes. The largest plumes are in Arkansas and Oklahoma. There are fire locations spread across the Texas and the Mississippi Valley as well. The next image, courtesy EPA AIRNOW, shows the forecast for AQI values for Texas. The Houston-Galeveston region was forecasted at a code orange, which is Unsafe for Sensitive Groups. Although, there are fires and smoke surrounding this region, this code orange is due to ozone, with some additional help from P.M. 2.5. The plot below shows the ozone data (ug/m3) for the Houston metro area.
 |  |
 |
The first image below shows the GEOS-5 Chemistry and Aerosol Forecast AOD overlaid with the HMS fire locations on Google Earth. Some of the raised values correspond to close fire locations in the Mississippi Valley.The raised AOD for the Northeast region is most likely due to sulfates. The animation beside that was taken from GASP AOD. Towards the end of this animation, you can see the encroaching smoke plumes moving from western Texas to the east. Also, you can see raised AOD values for the small plumes that correlate to the plumes in the HMS images.
 |  |