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Original Research Papers

Saharan dust absorption and refractive index from aircraft-based observations during SAMUM 2006

Authors:

Andreas Petzold ,

Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, DE
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Katharina Rasp,

Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, DE
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Bernadett Weinzierl,

Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, DE
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Michael Esselborn,

Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, DE
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Thomas Hamburger,

Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, DE
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Andreas Dörnbrac,

Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, DE
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Konrad Kandler,

Applied Geosciences Department, Darmstadt University of Technology, DE
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Lothar Schütz,

Institute for Atmospheric Physics, Johannes Gutenberg-University, DE
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Peter Knippertz,

Institute for Atmospheric Physics, Johannes Gutenberg-University, DE
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Markus Fiebig,

Department for Atmospheric and Climate Research, Norwegian Institute for Air Research, NO
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Aki Virkkula

Finnish Meteorological Institute, Air Quality Research, FI
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Abstract

During the Saharan Mineral Dust Experiment (SAMUM) conducted in summer 2006 in southeast Morocco, the complex refractive index of desert dust was determined from airborne measurements of particle size distributions and aerosol absorption coefficients at three different wavelengths in the blue (467 nm), green (530 nm) and red (660 nm) spectral regions. The vertical structure of the dust layers was analysed by an airborne high spectral resolution lidar (HSRL). The origin of the investigated dust layers was estimated from trajectory analyses, combined with Meteosat 2nd Generation (MSG) scenes and wind field data analyses. The real part n of the dust refractive index was found almost constant with values between 1.55 and 1.56, independent of the wavelength. The values of the imaginary part k varied between the blue and red spectral regions by a factor of three to ten depending on the dust source region. Absolute values of kranged from 3.1 × 10−3 to 5.2 × 103 at 450 nm and from 0.3 × 10−3 to 2.5 × 10−3 at 700 nm. Groupings ofk values could be attributed to different source regions.

How to Cite: Petzold, A., Rasp, K., Weinzierl, B., Esselborn, M., Hamburger, T., Dörnbrac, A., Kandler, K., Schütz, L., Knippertz, P., Fiebig, M. and Virkkula, A., 2009. Saharan dust absorption and refractive index from aircraft-based observations during SAMUM 2006. Tellus B: Chemical and Physical Meteorology, 61(1), pp.118–130. DOI: http://doi.org/10.1111/j.1600-0889.2008.00383.x
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  Published on 01 Jan 2009
 Accepted on 29 Jul 2008            Submitted on 19 Dec 2007

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