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| Titel |
Atmospheric dust modeling from meso to global scales with the online NMMB/BSC-Dust model – Part 2: Experimental campaigns in Northern Africa |
| VerfasserIn |
K. Haustein, C. Pérez, J. M. Baldasano, O. Jorba, S. Basart, R. L. Miller, Z. Janjic, T. Black, S. Nickovic, M. C. Todd, R. Washington, D. Müller, M. Tesche, B. Weinzierl, M. Esselborn, A. Schladitz |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 12, no. 6 ; Nr. 12, no. 6 (2012-03-23), S.2933-2958 |
| Datensatznummer |
250010944
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| Publikation (Nr.) |
 copernicus.org/acp-12-2933-2012.pdf |
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| Zusammenfassung |
| The new NMMB/BSC-Dust model is intended to provide short to medium-range
weather and dust forecasts from regional to global scales. It is an online
model in which the dust aerosol dynamics and physics are solved at each model
time step. The companion paper (Pérez et al., 2011) develops the dust model
parameterizations and provides daily to annual evaluations of the model for
its global and regional configurations. Modeled aerosol optical depth (AOD)
was evaluated against AERONET Sun photometers over Northern Africa, Middle
East and Europe with correlations around 0.6–0.7 on average without dust
data assimilation. In this paper we analyze in detail the behavior of the
model using data from the Saharan Mineral dUst experiment (SAMUM-1) in 2006
and the Bodélé Dust Experiment (BoDEx) in 2005. AOD from satellites
and Sun photometers, vertically resolved extinction coefficients from lidars
and particle size distributions at the ground and in the troposphere are
used, complemented by wind profile data and surface meteorological
measurements. All simulations were performed at the regional scale for the
Northern African domain at the expected operational horizontal resolution of
25 km. Model results for SAMUM-1 generally show good agreement with
satellite data over the most active Saharan dust sources. The model
reproduces the AOD from Sun photometers close to sources and after long-range
transport, and the dust size spectra at different height levels. At this
resolution, the model is not able to reproduce a large haboob that occurred
during the campaign. Some deficiencies are found concerning the vertical dust
distribution related to the representation of the mixing height in the
atmospheric part of the model. For the BoDEx episode, we found the diurnal
temperature cycle to be strongly dependant on the soil moisture, which is
underestimated in the NCEP analysis used for model initialization. The low
level jet (LLJ) and the dust AOD over the Bodélé are well reproduced.
The remaining negative AOD bias (due to underestimated surface wind speeds)
can be substantially reduced by decreasing the threshold friction velocity in
the model. |
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