7.8
Precipitation variability over East Antarctic as recorded at Mawson, Casey and Davis
Glenn R. McGregor, University of Birmingham, Birmingham, United Kingdom; and D. M. Bewley and G. Marshall
Forty years of daily precipitation event data for Mawson, Davis and Casey are analysed in order to investigate the spatial and temporal variability of precipitation in east Antarctic. The dependence of precipitation on the surface and upper air atmospheric circulation is also investigated. For Casey the annual total of precipitation events show a statistically significant increase (at the 10 per cent level) since 1961, although the variation around the linear fit is large. Mawson and Davis reveal no statistically significant trends in the number of precipitation events but are characterized by considerable variability at the inter-annual, 3-year, 7-year and decadal timescales. Analysis of precipitation events in relation to synoptic to hemispheric scale climate mechanisms revealed that precipitation variability is associated with synoptic forcing at the inter-annual timescale. Slower modes of climatic variability such as the Antarctic Circumpolar Wave, ENSO and the Inter-decadal Pacific Oscillation appear to be important determinants of precipitation variability at longer timescales.
Session 7, The Southern Hemisphere oceans and the cryosphere
Tuesday, 25 March 2003, 1:30 PM-5:15 PM
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