Dust storms as a factor of atmospheric air pollution in the Aral Sea basin

The Aral Sea Basin is considered as a region with increased rates of atmospheric air pollution by aerosols of arid origin. It is conditioned by the aridity of the climate and the presence of a great number of natural sources of aerosols emission to the atmosphere. The average annual number of days with dust storms varies from 20 to 67, while the maximum reaches up to 108-146 days with dust storms in separate years. The dusty and salty aerosol is the indispensable component and satellite of the dust storms in the region. The solonchaks (salty pans), secondary salinized irrigated lands and exposed bottom of the Aral Sea serve as natural sources of such kind of atmospheric pollution. Solonchaks, occupying the area of about 150 thousand km of the Aral Basin, create the powerful basis for development of aeolian processes, and, consequently, saltydust emission. This paper presents the climatic characteristics of the dust storms in the Aral Sea region, and quantitative assessment of salty-dust emission from the Aral Sea surface, its dried off bottom and surrounding solonchaks. Distribution of components of aerosols by the height and remoteness from the sources of emission, routes and distance of transportation of atmospheric aerosols from the dried bottom of the Aral Sea to the adjacent areas are studied.