ACPD Atmospheric Chemistry and Physics Discussions ACPD 1680-7375 Copernicus GmbH Göttingen, Germany 10.5194/acpd-9-13177-2009 Patterns of Saharan dust transport over the Atlantic: winter vs. summer, based on CALIPSO first year data Ben-Ami Y. 1 Koren I. 1 Altaratz O. 1 Department of Environmental Sciences and Energy Research, Weizmann Institute of Science, Rehovot, Israel 15 06 2009 9 3 13177 13198 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys-discuss.net/9/13177/2009/acpd-9-13177-2009.html The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/9/13177/2009/acpd-9-13177-2009.pdf

One of the most important factors that determines the transported dust effect is its vertical distribution in the atmosphere. Until the launch of the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO), the vertical distribution was studied mostly by in-situ measurements and models. CALIPSO, as a part of the A-Train constellation has opened an opportunity to study the transported dust vertical structure in a large number of events (sufficient statistics). <br><br> In this study the vertical structure of Saharan dust and stratiform clouds is analyzed over the Atlantic Ocean for the 2006–2007 winter (December–February) and the summer of 2006 (June–August). By using CALIPSO backscatter measurements over the dust route, we describe the differences in dust transport between the seasons. We show a bi-modal distribution of the average dust plumes height in both seasons (it is less clear in the winter). It suggests that a significant part of the dust is transported near and within the marine boundary layer and interacts with shallow clouds on both seasons.

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