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| Titel |
Temporal variability of mineral aerosol in the South Patagonia |
| VerfasserIn |
Zihan Qu, Rémi Losno, Emilie Journet, Jacobo Salvado, Daniela Bulnes, Fabrice Monna, Jean-Paul Quisefit, Alexie Heimburger, Pablo Ristori, Eduardo Jaime Quel, Yves Balkanski |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250111840
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| Publikation (Nr.) |
 EGU/EGU2015-11985.pdf |
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| Zusammenfassung |
| Patagonia (South America) is a major atmospheric mineral dust source in the South
Hemisphere. The input of Patagonian dust plays a critical role in the biogeochemistry of
Southern Ocean. From November 2011 to August 2014, aerosol samples were continuously
collected on a weekly basis in Río Gallegos (69.32Ë W, 51.60Ë S), by the south Patagonia
east coast. This three-year measurement is the first long term time series of mineral dust
concentrations obtained in the sub-Antarctic region. Backward trajectories by HYSPLIT
model showed that up to 90% of air mass arrived at Río Gallegos originated from the west
side (between NNW and SSW) of sampling site. Amounts of Al, Si and Fe were determined
by XRF analysis. The compositions of the three elements remained stable during the three
years samplings. Weekly dust concentrations measured in South Patagonia varied from 0.08
to 3.67Âμg.m-3 and reveals a strong seasonal variation pattern. Average winter dust
concentrations could decrease down to five times lower than in other seasons. Higher
wind speeds unexpectedly did not result in higher dust concentrations. However,
variations of the temperature and the air relative humidity well correlated with the dust
concentration variation. This suggests that surface soil moisture changes are the primary
regulating factor of dust concentration variation in Patagonia. Land frozen effect
was potentially another factor resulting low level of dust concentration in winter.
These results permit the improvement of atmospheric dust modelling in the South
Hemisphere.
This work is in SOLAS scope, and is supported by French project “Dust From Patagonia”
(CNRS-INSU, LEFE/CHAT) and France-Argentina cooperation program “ASAR”
(ECOS-Sud). |
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