Dust sources and deposition of aeolian materials in Iceland

Iceland has about 22,000 km² of sandy deserts that are a major source of atmospheric dust. Icelandic dust is mostly basaltic volcanic glass, which is rather unique for global dust sources. The dust comes mostly from two sources: confined plume areas and extensive sandy deserts. Major plume sources are identified by field observations and satellite images, while Icelandic sandy deserts have been mapped. Measured erosion fluxes commonly reach 500 to > 2,000 kg m^-1 day^-1 during storms. A map showing major plume areas and their deposition areas and a map showing deposition from sandy areas are produced and subsequently combined to obtain an overview of aeolian deposition in Iceland. Deposition rates range from < 25 g m^-2 yr^-1 far from aeolian sources to > 500 g m^-2 yr^-1 near or within major sandy areas. These numbers are higher than deposition rates reported for other major global dust areas. The spatial distribution of aeolian deposition has a key influence on important soil parameters, such as clay content and organic matter.