FIG. 1.

African and Asian dust storms. Stars identify dust cloud source regions, and arrows identify dust clouds and the general direction of movement. (A) NASA image, via the moderate-resolution imaging spectroradiometer (MODIS) aboard the Terra satellite, of a dust storm blowing over the Sea of Japan on 1 April 2002. (Image courtesy of Jacques Descloitres, MODIS Land Rapid Response Team, NASA/Goddard Space Flight Center.) (B) NASA image, via MODIS, of a dust storm blowing out of Africa over the Mediterranean Sea in the direction of Turkey. The black spot in the tongue of dust is the Troödos mountain range of Cyprus, which protrudes through the top of the dust cloud. The image was taken on 25 February 2006. (Courtesy of Jeff Schmaltz, MODIS Land Rapid Response Team, NASA/Goddard Space Flight Center.) (C) NASA Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) image of a large dust cloud blowing across the Atlantic. The image was taken on 19 July 2005 and is courtesy of the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE. This dust cloud impacted the air quality in Florida. Airborne particle measurements taken by the author with a handheld laser particle counter south of Tampa Bay, FL, went from 2.6 × 10⁶ m⁻³ on 15 July 2005 (normal clear atmosphere) to 26.1 × 10⁶ m⁻³ on 25 July 2005 (dust conditions). Over 90% of the particles ranged from >0.3 to 0.5 μm in size.