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| Titel |
High-resolution provenance of desert dust deposited on Mt. Elbrus, Caucasus in 2009-2012 using snow pit and firn core records |
| VerfasserIn |
S. Kutuzov, M. Shahgedanova, V. Mikhalenko, P. Ginot, I. Lavrentiev, S. Kemp |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1994-0416
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| Digitales Dokument |
URL |
| Erschienen |
In: The Cryosphere ; 7, no. 5 ; Nr. 7, no. 5 (2013-09-24), S.1481-1498 |
| Datensatznummer |
250085162
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| Publikation (Nr.) |
 copernicus.org/tc-7-1481-2013.pdf |
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| Zusammenfassung |
| The first record of dust deposition events on Mt. Elbrus, Caucasus Mountains
derived from a snow pit and a shallow firn core is presented for the
2009–2012 period. A combination of isotopic analysis, SEVIRI red-green-blue
composite imagery, MODIS atmospheric optical depth fields derived using the
Deep Blue algorithm, air mass trajectories derived using the HYSPLIT model
and analyses of meteorological data enabled identification of dust source
regions with high temporal (hours) and spatial (ca. 20–100 km) resolution.
Seventeen dust deposition events were detected; fourteen occurred in
March–June, one in February and two in October. Four events originated in
the Sahara, predominantly in northeastern Libya and eastern Algeria.
Thirteen events originated in the Middle East, in the Syrian Desert and
northern Mesopotamia, from a mixture of natural and anthropogenic sources.
Dust transportation from Sahara was associated with vigorous Saharan
depressions, strong surface winds in the source region and mid-tropospheric
southwesterly flow with daily winds speeds of 20–30 m s−1 at
700 hPa level. Although these events were less frequent than those
originating in the Middle East, they resulted in higher dust concentrations
in snow. Dust transportation from the Middle East was associated with weaker
depressions forming over the source region, high pressure centred over or
extending towards the Caspian Sea and a weaker southerly or southeasterly
flow towards the Caucasus Mountains with daily wind speeds of
12–18 m s−1 at 700 hPa level. Higher concentrations of nitrates and
ammonium characterised dust from the Middle East deposited on Mt. Elbrus in
2009 indicating contribution of anthropogenic sources. The modal values of
particle size distributions ranged between 1.98 μm and
4.16 μm. Most samples were characterised by modal values of
2.0–2.8 μm with an average of 2.6 μm and there was no
significant difference between dust from the Sahara and the Middle East. |
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