August 4, 2009
Smoke from Alaska Fires Spreads across Northern U.S.; New Fires in California, Oregon, and Washington
Smoke from the fires in Alaska and Canada spread further into interior portions of the U.S. today, as shown in the most recent NOAA Hazard Mapping System (HMS) map (below on upper left). Residual smoke was evident in Terra MODIS true color imagery over the Midwest, in addition to the bright white clouds associated with a Mesoscale Convective System (below on upper right, overlaid with AQI values in Google Earth; images courtesy of SSEC MODIS Today and AIRNow). Smoke from new fires in California, Oregon, and Washington state is also visible in the Terra MODIS true color imagery (below on lower left, overlaid with AQI values in Google Earth; images courtesy of SSEC MODIS Today and AIRNow). Today’s MODIS AOD image is not available from the IDEA site – I’ll monitor the site and upload the AOD image when it becomes available, hopefully tomorrow.
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The National Interagency Fire Center reported two new wildfires in Alaska today, both near Fairbanks; residences are threatened. PM2.5 air quality in the Fairbanks area is currently Code Orange (Unhealthy for Sensitive Groups); yesterday’s 24-hour average PM2.5 was 72.0 μg/m³, which is in the Code Red (Unhealthy) range. The usual MODIS true color subsets we use for Alaska haven’t been updated on the MODIS Rapid Response site, so I can only show you the southeast portion of Alaska (below). Even for this small portion of the state, thick smoke is visible, mixed in with the clouds along the coast.
Air Quality Action Days were issued for ozone today in the Washington, DC-Baltimore-Philadelphia corridor, but based on the data from AIRNow (below on upper left), I don’t think 8-hour average ozone values reached the Code Orange range, which is good news for residents (like me). In DC, we certainly experienced hot, humid, and hazy conditions, which typically correspond to poor air quality. You can get an idea of the haze from the McMillan Reservoir webcam shot from noon today (below on right), although PM2.5 levels remained in the Code Yellow (Moderate) range, as shown in the loop of today’s AQI values (below on lower left, courtesy of AIRNow).
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