elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Impressum | Kontakt | English
Schriftgröße: [-] Text [+]

Dust emissions over the Sahel associated with the West African monsoon intertropical discontinuity region: A representative case-study

Bou Karam, D. und Flamant, C. und Knippertz, P. und Reitebuch, O. und Pelon, J. und Chong, M. und Dabas, A. (2008) Dust emissions over the Sahel associated with the West African monsoon intertropical discontinuity region: A representative case-study. Quarterly Journal of the Royal Meteorological Society, 134, Seiten 621-634. DOI: 10.1002/QJ.244.

[img]
Vorschau
PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
2MB

Offizielle URL: http://www3.interscience.wiley.com/journal/113388514/home

Kurzfassung

Near-dawn airborne lidar and dropsonde observations acquired on 7 July 2006, during the African Monsoon Multidisciplinary Analysis (AMMA) Special Observing Period 2a1, were used to investigate dust mobilization, lifting and transport in the intertropical discontinuity (ITD) region over western Niger. Atmospheric reflectivity data from the LEANDRE 2 lidar system enabled us to analyse the structure of dust plumes in the context of wind and thermodynamic information provided by the WIND lidar system and dropsondes. Dust mobilization was mainly observed in two locations: (a) within the monsoon flow as the result of the passage of a density current originating from a mesoscale convective system over southwest Niger, and (b) at the leading edge of the monsoon flow where the near-surface winds and turbulence were strong, because the monsoon flow was behaving as an intrusive density current. The circulation in the head of the monsoon density current lifted the mobilized dust towards the wake, along an isentropic surface. Behind and away from the leading edge, some of the mobilized dust was observed to mix across the monsoon-harmattan interface, due to the existence of mechanical shear above the monsoon layer. The dust thus becomes available for long-range transport by the harmattan. Because dust sources are widespread over the Sahel and presumably active on many days when the ITD is located in this region during summer, dust emissions associated with the described mechanism may influence the radiation budget over West Africa.

Dokumentart:Zeitschriftenbeitrag
Titel:Dust emissions over the Sahel associated with the West African monsoon intertropical discontinuity region: A representative case-study
Autoren:
AutorenInstitution oder E-Mail-Adresse der Autoren
Bou Karam, D.Univ. Pierre et Marie Curie, Paris, F
Flamant, C.Univ. Pierre et Marie Curie, Paris, F
Knippertz, P.Johannes Gutenberg-Univ. Mainz
Reitebuch, O.NICHT SPEZIFIZIERT
Pelon, J.Univ. Pierre et Marie Curie, Paris, F
Chong, M.Univ. de Toulouse, Toulouse, F
Dabas, A.Meteo-France, Toulouse, F
Datum:2008
Erschienen in:Quarterly Journal of the Royal Meteorological Society
Referierte Publikation:Ja
In Open Access:Nein
In SCOPUS:Ja
In ISI Web of Science:Ja
Band:134
DOI :10.1002/QJ.244
Seitenbereich:Seiten 621-634
Status:veröffentlicht
Stichwörter:AMMA, Wind Lidar, Dust
HGF - Forschungsbereich:Verkehr und Weltraum (alt)
HGF - Programm:Weltraum (alt)
HGF - Programmthema:W EO - Erdbeobachtung
DLR - Schwerpunkt:Weltraum
DLR - Forschungsgebiet:W EO - Erdbeobachtung
DLR - Teilgebiet (Projekt, Vorhaben):W - Projekt ADM II (alt)
Standort: Oberpfaffenhofen
Institute & Einrichtungen:Institut für Physik der Atmosphäre > Lidar
Hinterlegt von: Oliver Reitebuch
Hinterlegt am:08 Dez 2008
Letzte Änderung:20 Okt 2014 14:33

Nur für Mitarbeiter des Archivs: Kontrollseite des Eintrags

Blättern
Suchen
Hilfe & Kontakt
Informationen
electronic library verwendet EPrints 3.3.12
Copyright © 2008-2013 Deutsches Zentrum für Luft- und Raumfahrt (DLR). Alle Rechte vorbehalten.