 |
| Titel |
Aerosol distribution over the western Mediterranean basin during a Tramontane/Mistral event |
| VerfasserIn |
T. Salameh, P. Drobinski, L. Menut, B. Bessagnet, C. Flamant, A. Hodzic, R. Vautard |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 25, no. 11 ; Nr. 25, no. 11 (2007-11-29), S.2271-2291 |
| Datensatznummer |
250015940
|
| Publikation (Nr.) |
 copernicus.org/angeo-25-2271-2007.pdf |
|
|
|
|
|
| Zusammenfassung |
This paper investigates experimentally and numerically the time
evolution of the spatial distribution of aerosols over the Western
Mediterranean basin during the 24 March 1998 Mistral event documented
during the FETCH experiment. Mistral and Tramontane are very
frequently northerly wind storms (5–15 days per month) accelerated
along the Rh\^one and Aude valleys (France) that can transport
natural and anthropogenic aerosols offshore as far as a few
hundred kilometers, which can, in turn, have an impact on the
radiation
budget over the Mediterranean Sea and on precipitation.
The spatial distribution of aerosols was documented by means of
the airborne lidar LEANDRE-2 and space-borne radiometer SeaWIFS,
and a validated mesoscale chemical simulation using the
chemistry-transport model CHIMERE with an aerosol module, forced
by the non-hydrostatic model MM5.
This study shows that: (1) the Mistral and Tramontane contribute
to the offshore exportation of a large amount of aerosols
originally emitted over continental Europe (in particular, ammonium
nitrate in the particulate phase and sulfates) and along the shore
from the industrialized and urban areas of Fos-Berre/Marseille.
The amount of aerosol loading solely due to the Mistral and
Tramontane is as large as 3–4 times the background aerosol amount
and the contribution of sea-salt particles to the total aerosol
loading and optical depth ranges from 1 to 10% even in such
stormy conditions; (2) the aerosol concentration pattern is very
unsteady as a result of the time evolution of the two winds (or
Genoa cyclone position): The Tramontane wind prevails in the
morning hours of 24 March, leaving room for the Mistral wind and
an unusually strong Ligurian outflow in the afternoon. The Genoa
surface low contributes to advect the aerosols along a cyclonic
trajectory that skirts the North African coast and reaches Italy.
The wakes trailing downstream the Massif Central and the Alps
prevent any horizontal diffusion of the aerosols and can, at
times, contribute to aerosol stagnation. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|