 |
| Titel |
Parameterization of dust emissions in the global atmospheric chemistry-climate model EMAC: impact of nudging and soil properties |
| VerfasserIn |
M. Astitha, J. Lelieveld  , M. Abdel Kader, A. Pozzer, A. Meij |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 12, no. 22 ; Nr. 12, no. 22 (2012-11-22), S.11057-11083 |
| Datensatznummer |
250011615
|
| Publikation (Nr.) |
 copernicus.org/acp-12-11057-2012.pdf |
|
|
|
|
|
| Zusammenfassung |
| Airborne desert dust influences radiative transfer, atmospheric chemistry
and dynamics, as well as nutrient transport and deposition. It directly and
indirectly affects climate on regional and global scales. Two versions of a
parameterization scheme to compute desert dust emissions are incorporated
into the atmospheric chemistry general circulation model EMAC
(ECHAM5/MESSy2.41 Atmospheric
Chemistry). One uses a globally uniform soil particle size
distribution, whereas the other explicitly accounts for different soil
textures worldwide. We have tested these two versions and investigated the
sensitivity to input parameters, using remote sensing data from the Aerosol
Robotic Network (AERONET) and dust concentrations and deposition
measurements from the AeroCom dust benchmark database (and others). The two
versions are shown to produce similar atmospheric dust loads in the
N-African region, while they deviate in the Asian, Middle Eastern and
S-American regions. The dust outflow from Africa over the Atlantic Ocean is
accurately simulated by both schemes, in magnitude, location and
seasonality. Approximately 70% of the modelled annual deposition data and
70–75% of the modelled monthly aerosol optical depth (AOD) in the
Atlantic Ocean stations lay in the range 0.5 to 2 times the observations for
all simulations. The two versions have similar performance, even though the
total annual source differs by ~50%, which underscores the
importance of transport and deposition processes (being the same for both
versions). Even though the explicit soil particle size distribution is
considered more realistic, the simpler scheme appears to perform better in
several locations. This paper discusses the differences between the two
versions of the dust emission scheme, focusing on their limitations and
strengths in describing the global dust cycle and suggests possible future
improvements. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|