October 28, 2009
Dust over Western California and Moderate PM2.5 AQI Levels near the Great Lakes
The blowing dust that led to the Air Quality Action Days across the Southwestern US yesterday is visible in MODIS Terra "true color" image(left figure overlaid in Google Earth) extending over portions of northern Baja and Gulf of California. The top right image (courtesy of Airnowtech) is a timeseries of the hourly PM2.5 ground monitors managed by the San Joaquin Valley Air Pollution Control District. A remarkable improvement on the air quality has been experienced on the PM2.5 timeseries with concentrations less than 20 ug/m3 recorded for today, compared to yesterday's highs.The AOD recorded by the MODIS sensors in Terra and Aqua over EPA's region 9 is associated with the area of coverage of this blown dust.
PM2.5 AQI levels were moderate in Southern California, Wisconsin, Illinois, Indiana and Ohio were Moderate according to EPA's Airnow. No major smoke and fire activity, to impact air quality, was reported by NOAA Hazard Mapping System Fire and Smoke Product and the National Interagency Fire Center.
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