U.S. Air Quality

Midwest haze

Fine particle air pollution continued to be an issue in the Midwest today. Haze was particularly visible in Wisconsin, Minnesota, Illinois, Michigan, Indiana, and Iowa, and to a lesser extent in South Dakota. The MODIS aerosol optical depth was around 0.5. Fine particle concentrations were code yellow, with a peak in Chicago of about 30 ug/m3 (24 hour average).