July 28, 2008
Northern California is Still Burning; Hazy in the Northeast
As we start the last week of July, air quality varies across the nation, as shown in today’s AQI loops for ozone (below on left) and PM2.5 (below on right). There are scattered pockets of Code Orange (Unhealthy for Sensitive Groups) ozone, while PM2.5 is in the Code Yellow (Moderate) range for most of the eastern United States.
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The fires in northern California that Ray referred to yesterday are still burning and creating Code Red (Unhealthy) air quality conditions, as shown in the PM2.5 loop above. Today’s MODIS Terra true color image for the USA 1 region (below on left) shows concentrated smoke in the vicinity of the fires and a smoke plume dispersing eastward into Oregon and Idaho. The corresponding MODIS Terra AOD image from EPA region 10 (below on right) indicates elevated AOD associated with the dispersing smoke plume. Smoke associated with these fires is currently visible on the ground at Sun Valley, ID (KSUN), Fallon Naval Air Station, NV (KNFL), and San Luis Obispo, CA (KSBP).
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The Hazard Mapping System Fire and Smoke Product (below) illustrates the extent of the smoke from the fires in California and Canada.
It’s also hazy in the Northeast today, as seen in the MODIS Terra true color image for the USA 4 region (below on left). Although clouds over the Mid-Atlantic region blocked measurement of AOD in many areas this morning, elevated AOD levels associated with the hazy airmass are evident over New York in the MODIS Terra AOD image from EPA region 1-3 (below on right). It’s possible that the Canadian smoke plume that Ray discussed yesterday is also contributing to the hazy conditions in the Northeast. Despite the haze, air quality at the surface has not deteriorated too much today, with widespread Code Yellow PM2.5 readings, as discussed above.
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There won’t be any relief from the haze tomorrow, as a short-lived area of high pressure builds into Mid-Atlantic region, bringing clear skies and light winds. These are ideal conditions for ozone formation and particle build-up, and many municipalities in the Eastern Unites States have forecasted Code Orange air quality days for Tuesday. The maps below show the AQI forecast for Tuesday for the Eastern United States (below on right) and the Western United States (below on left) in Google Earth. Code Orange air quality is also forecast for several areas in California. If you live in an affected region, keep an eye on the air quality tomorrow and take appropriate measures to protect your health.
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