2004), An examination of the precipitation delivery mechanisms for Dolleman

The variability of size and source of significant precipitation events were studied at an Antarctic ice core drilling site: Dolleman Island (DI), located on the eastern coast of the Antarctic Peninsula. Significant precipitation events that occur at DI were temporally located in the ECMWF re-analysi...

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Bibliographic Details
Main Authors: Andrew Russell, Glenn R. Mcgregor, Gareth J. Marshall
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.425.4133
http://bura.brunel.ac.uk/bitstream/2438/6032/5/Russell_et_al_2004_finalsubmitted.pdf
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Summary:The variability of size and source of significant precipitation events were studied at an Antarctic ice core drilling site: Dolleman Island (DI), located on the eastern coast of the Antarctic Peninsula. Significant precipitation events that occur at DI were temporally located in the ECMWF re-analysis data set, ERA-40. The annual and summer precipitation totals from ERA-40 at DI both show significant increases over the re-analysis period. Three dimensional backwards air parcel trajectories were then run for 5-days using the ECMWF ERA-15 wind fields. Cluster analyses were performed on two sets of these backwards trajectories: all days in the range 1979-1992 (the climatological timescale) and a subset of days when a significant precipitation event occurred. The principal air mass sources and delivery mechanisms were found to be the Weddell Sea via lee cyclogenesis, the South Atlantic when there was a weak Circumpolar Trough (CPT) and the South Pacific when the CPT was deep. The occurrence of precipitation bearing air masses arriving via a strong CPT was found to have a significant correlation with the Southern Annular Mode (SAM), however, the arrival of air masses from the same region over the climatological timescale