ACP Atmospheric Chemistry and Physics ACP Atmos. Chem. Phys. 1680-7324 Copernicus Publications Göttingen, Germany 10.5194/acp-9-1173-2009 Saharan dust transport and deposition towards the tropical northern Atlantic Schepanski K. 1 2 Tegen I. 1 Macke A. 2 Leibniz Institute for Tropospheric Research, Leipzig, Germany Leibniz-Institute of Marine Sciences, IFM-GEOMAR, Kiel, Germany 16 02 2009 9 4 1173 1189 Copyright: © 2009 K. Schepanski et al. 2009 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://acp.copernicus.org/articles/9/1173/2009/acp-9-1173-2009.html The full text article is available as a PDF file from https://acp.copernicus.org/articles/9/1173/2009/acp-9-1173-2009.pdf

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 typical 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 to activation frequency and dust emission. Limitations of using satellite retrievals to estimate dust deposition are highlighted.

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