August 6, 2012
Unhealty ozone levels in Central US and Southern California; High levels of PM2.5 in Idaho
Compared to the last few days, the air quality in the Great Lakes and in the Northeast region showed significant improvement, with ozone and PM2.5 concentrations ranging mostly between good and moderate levels, as can be seen below (left, right, respectively).
Code orange in terms of ozone was observed in Central US (mainly Oklahoma, Missouri), Southern Illinois, and Southern California from the bottom portion of the San Joaquin Valley down to San Diego.
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MODIS Terra AOD retrievals show a region with high values across Montana (left), which are linked to the ongoing wildfires (right) in Oregon, California, Nevada, and Idaho. Unhealthy levels of PM2.5 (code orange as well) were observed in Idaho and it is very likely that they were also caused by the smoke in the region (top, right).
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