High-Resolution Image

MODIS images of influx of pollution to the Bay of Bengal (top part) and dust (lower part) from India into the Arabian Sea. The left panels show a color composite of the regions being observed by MODIS. The center panel is the MODIS analysis of the aerosol column concentration, expressed by the optical thickness, and the right column is the fraction of aerosol that is composed of particles smaller than 1µm, typical of air pollution or smoke from vegetation fires. By showing that the aerosol in the top panels is dominated by submicron particles, MODIS identifies that the aerosol is pollution from human activity. In the lower panel by identifying significantly lower contribution of the submicron particles we can conclude that the aerosol is desert dust. This identification of aerosol by MODIS is expected to be useful in studying the effect of aerosol on climate and the hydrological cycle.

(submitted by Yoram Kaufman and Rong-Rong Li)