Plumes of dingy gray haze collected off the east coast of the United States on July 19, 2007. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this image the same day.
In this picture, the haze contrasts with nearby clouds, thanks to its darker color. While the clouds appear bright white, the haze is medium gray. The source of the haze is not apparent in this image. The U.S. Air Quality blog at the University of Maryland, Baltimore County described smoke from Canadian fires entering the United States the day before. Smog from nearby U.S. cities, however, could also be the culprit.
NASA image courtesy the MODIS Rapid Response Team at NASA GSFC. The Rapid Response Team provides daily images of this region.