March 25, 2009
Code Green Air Quality Dominates U.S.
The swath of code yellow (moderate) PM2.5 levels we have been discussing over the past few days on the blog is getting smaller, now just shown by a relatively small area of yellow dots in the AIRNow image of PM2.5 values, below left. Southern Texas and California also saw isolated code yellow PM2.5 readings, but otherwise the country is enjoying good air quality (code green). NOAA’s HMS shows that some fires continue in the Central Plains, although these do not appear to be significantly affecting air quality at the ground level.
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Today’s Aqua true color composite shows widespread cloudiness in the east, upper midwest, and northwest. As a result, AOD readings are limited (Aqua actually got more AOD data than Terra, but the corresponding Terra true color image was for some reason incomplete). Below right is the Aqua AOD image, showing some elevated particle levels in western Arizona and Nevada.
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