Mineral base-cation deposition in Asia

Efforts are being made to model the role of base-cation deposition due to wind-blown dust particles from arid and semi-arid regions in Central and Eastern Asia. In this paper, we estimate base-cation deposition in Asia on a one-degree spatial resolution in the region from Pakistan to Japan, and from Indonesia to Russia resulting from emissions from arid and semi-arid regions in China and Mongolia. Fluxes of base-cation rich soils into the atmosphere are estimated based on meteorological and land use information. The long-range transport and deposition of these particles are modeled using a multi-layer long-range transport model. Atmospheric concentrations and deposition fluxes (both wet and dry) of base-cation rich soils are estimated on a monthly basis for the springtime, when dust storms are most active. The calculated fluxes are compared to observations and are also used in estimations of acidic “Critical Loads” for Asia.