References

ACP

Atmospheric Chemistry and Physics

ACP

1680-7324

Copernicus GmbH

Göttingen, Germany

10.5194/acp-11-10733-2011

Dust optical properties over North Africa and Arabian Peninsula derived from the AERONET dataset

Kim

¹ ² ⁴ Chin

² Yu

² ³ Eck

T. F.

² ⁴ Sinyuk

² ⁵ Smirnov

² ⁵ Holben

B. N.

Joint Center for Earth Systems Technology, University of Maryland Baltimore County, Baltimore, Maryland, USA

NASA Goddard Space Flight Center, Greenbelt, Maryland, USA

Earth System Science Interdisciplinary Center, University of Maryland, College Park, Maryland, USA

Universities Space Research Association, Columbia, Maryland, USA

Sigma Space Corporation, Lanham, Maryland, USA

28 10 2011

11 20 10733 10741

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.net/11/10733/2011/acp-11-10733-2011.html

The full text article is available as a PDF file from http://www.atmos-chem-phys.net/11/10733/2011/acp-11-10733-2011.pdf

Dust optical properties over North Africa and the Arabian Peninsula are extracted from the quality assured multi-year datasets obtained at 14 sites of the Aerosol Robotic Network (AERONET). We select the data with (a) large aerosol optical depth (AOD ≥ 0.4 at 440 nm) and (b) small Ångström exponent (Å<sub>ext</sub> ≤ 0.2) for retaining high accuracy and reducing interference of non-dust aerosols. The result indicates that the major fraction of high aerosol optical depth days are dominated by dust over these sites even though it varies depending on location and time. We have found that the annual mean and standard deviation of single scattering albedo, asymmetry parameter, real refractive index, and imaginary refractive index for Saharan and Arabian desert dust is 0.944 ± 0.005, 0.752 ± 0.014, 1.498 ± 0.032, and 0.0024 ± 0.0034 at 550 nm wavelength, respectively. Dust aerosol selected by this method is less absorbing than the previously reported values over these sites. The weaker absorption of dust from this study is consistent with the studies using remote sensing techniques from satellite. These results can help to constrain uncertainties in estimating global dust shortwave radiative forcing.

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