U.S. Air Quality

Smoke from Fires Persists; Code Yellow PM2.5 in Parts of East; Code Green Ozone across the Country

Air quality across the nation is very similar to yesterday’s conditions. Today’s loops of AQI values (PM2.5 below on left, O3 below on right; courtesy of AIRNow) show widespread Code Yellow (Moderate) PM2.5 in many parts of the eastern U.S., while ozone was Code Green (Good) across the country.

The regional smoke plumes that have been discussed on the Blog for the past week continued today, and they are evident in satellite imagery in the Pacific Northwest and Southeast, although they do not appear to be seriously impacting surface air quality. Today’s MODIS Terra AOD image for region 4 (below on upper left, courtesy of IDEA) indicates slightly elevated AOD across the Southeast, and smoke is visible in the corresponding MODIS true color image, overlaid with AQI values and HMS fire “hotspots” in Google Earth (below on upper right, courtesy of UW MODIS Today, AIRNow, and HMS). There is a stationary front draped across the GA/SC border, with high pressure centered over the Gulf of Mexico, that helping the smoke in the region to persist. The situation is less clear, literally, in the Pacific Northwest, where today’s MODIS Terra AOD image for region 10 (below on lower left, courtesy of IDEA) indicates a small swath of very high AOD in Washington state, presumably from smoke, but it is not possible to definitively discern smoke amongst the clouds in the corresponding MODIS true color image, overlaid with AQI values in Google Earth (below on lower right, courtesy of UW MODIS Today and AIRNow).