March 27, 2009
Clouds still covering large areas in US; Good air quality in most of the country.
Today PM2.5 levels were good in most of the country with some exceptions in California, Texas, and Central US which were presenting moderate levels (top, left). Ozone levels were good.
Around the Great Lakes we can see moderate levels of PM2.5 which according to EPA forecast (National Outlook at AIRNow website) is due to "a weak upper-level ridge of high pressure over the region (...) reducing vertical mixing, trapping pollutants near the surface". Terra MODIS AOD map for this region can be seen in the image below (top, right).
Still low number of fires in US but in Mexico and Central America (bottom, left) it has increased substantially. Smoke is not visible in Terra MODIS image but the moderate conditions in Texas are probably related to those fires. According to SSD fire team at NOAA, haze from Redoubt volcano eruption could be seen in Nebraska, Iowa, Wisconsin, Michigan, across the Great Lakes. As we can see in the Terra MODIS image (bottom,right) there was too many clouds covering that region and also what seems to be a hazy area could be just an effect of the image contrast.
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