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Original Research Papers

Dust mobilization and transport in the northern Sahara during SAMUM 2006 – a meteorological overview

Authors:

Peter Knippertz ,

Institute for Atmospheric Physics, Johannes Gutenberg University Mainz, DE
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Albert Ansmann,

Leibniz Institute for Tropospheric Research, DE
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Dietrich Althausen,

Leibniz Institute for Tropospheric Research, DE
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Detlef Müller,

Leibniz Institute for Tropospheric Research, DE
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Matthias Tesche,

Leibniz Institute for Tropospheric Research, DE
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Eike Bierwirth,

Institute for Atmospheric Physics, Johannes Gutenberg University Mainz, DE
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Tilman Dinter,

Institute of Environmental Physics, University of Bremen, DE
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Thomas Müller,

Leibniz Institute for Tropospheric Research, DE
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Wolfgang Von Hoyningen-Huene,

Institute of Environmental Physics, University of Bremen, DE
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Kerstin Schepanski,

Leibniz Institute for Tropospheric Research; Leibniz-Institute for Marine Sciences, IfM-Geomar, DE
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Manfred Wendisch,

Institute for Atmospheric Physics, Johannes Gutenberg University Mainz, DE
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Bernd Heinold,

Leibniz Institute for Tropospheric Research, DE
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Konrad Kandler,

Institute for Applied Geosciences, Darmstadt University of Technology, DE
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Andreas Petzold,

Institute for Atmospheric Physics, German Aerospace Center, DE
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Lothar Schütz,

Institute for Atmospheric Physics, Johannes Gutenberg University Mainz, DE
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Ina Tegen

Leibniz Institute for Tropospheric Research, DE
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Abstract

The SAMUM field campaign in southern Morocco in May/June 2006 provides valuable data to study the emission, and the horizontal and vertical transports of mineral dust in the Northern Sahara. Radiosonde and lidar observations show differential advection of air masses with different characteristics during stable nighttime conditions and up to 5-km deep vertical mixing in the strongly convective boundary layer during the day. Lagrangian and synoptic analyses of selected dust periods point to a topographic channel from western Tunisia to central Algeria as a dust source region. Significant emission events are related to cold surges from the Mediterranean in association with eastward passing upper-level waves and lee cyclogeneses south of the Atlas Mountains. Other relevant events are local emissions under a distinct cut-off low over northwestern Africa and gust fronts associated with dry thunderstorms over the Malian and Algerian Sahara. The latter are badly represented in analyses from the European Centre for Medium–Range Weather Forecasts and in a regional dust model, most likely due to problems with moist convective dynamics and a lack of observations in this region. This aspect needs further study. The meteorological source identification is consistent with estimates of optical and mineralogical properties of dust samples.

How to Cite: Knippertz, P., Ansmann, A., Althausen, D., Müller, D., Tesche, M., Bierwirth, E., Dinter, T., Müller, T., Von Hoyningen-Huene, W., Schepanski, K., Wendisch, M., Heinold, B., Kandler, K., Petzold, A., Schütz, L. and Tegen, I., 2009. Dust mobilization and transport in the northern Sahara during SAMUM 2006 – a meteorological overview. Tellus B: Chemical and Physical Meteorology, 61(1), pp.12–31. DOI: http://doi.org/10.1111/j.1600-0889.2008.00380.x
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  Published on 01 Jan 2009
 Accepted on 11 Jul 2008            Submitted on 13 Dec 2007

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