Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 8 4 2008 10.5194/acpd-8-16061-2008 http://www.atmos-chem-phys-discuss.net/8/16061/2008/ http://www.atmos-chem-phys-discuss.net/8/16061/2008/acpd-8-16061-2008.html http://www.atmos-chem-phys-discuss.net/8/16061/2008/acpd-8-16061-2008.pdf 16061 16096 2008-08-22 Saharan dust transport and deposition towards the Tropical Northern Atlantic K. Schepanski kerstin.schepanski@tropos.de I. Tegen A. Macke Leibniz Institute for Tropospheric Research, Leipzig, Germany Leibniz-Institute of Marine Sciences, IFM-GEOMAR, Kiel, Germany We present a study of Saharan dust export towards the tropical North Atlantic using the regional dust emission, transport and deposition model LM-MUSCAT. Horizontal and vertical distribution of dust optical thickness, concentration, and dry and wet deposition rates are used to describe seasonality of dust export and deposition towards the eastern Atlantic for three exemplary months in different seasons. Deposition rates strongly depend on the vertical dust distribution, which differs with seasons. Furthermore the contribution of dust originating from the Bodélé Depression to Saharan dust over the Atlantic is investigated. A maximum contribution of Bodélé dust transported towards the Cape Verde Islands is evident in winter when the Bodélé source area is most active and dominant with regard activation frequency and dust emission. Limitations of using satellite retrievals to estimate dust deposition are highlighted. Banta, R M., Pichugina, Y L., and Brewer, W.: Turbulent velocity-variance profiles in the stable Boundary Layer generated by a nocturnal low-level jet, J. Atmos. Sci., 63, 2700–2719, 2006. 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