CLIMATOLOGY OF THE EAST ANTARCTIC ICE-SHEET (100-DEGREES-E TO 140-DEGREES-E) DERIVED FROM AUTOMATIC WEATHER STATIONS

A decade ago, automatic weather stations (AWS) were placed in remote areas of Antarctica where little or no information on the meteorological conditions was available. These stations report to the ARGOS data collection system onboard polar orbiting satellites of the NOAA series. The Australian National Antarctic Research Expeditions (ANARE) and the United States Antarctic Research Program (USARP) of the National Science Foundation (with logistic support from the French Expeditions Polaires Francaises (EPF)) have built up two AWS data nets in East Antarctica. There are a total of 16 stations in the area 55-degrees - 145-degrees-E and 65-degrees - 75-degrees-S, stretching from sea level to above 3000 m altitude. The records of 10 of these stations are sufficiently long to be adequate for a climatological study of the basic parameters of surface temperature, pressure, and wind and have been used in this study. The station data were reduced to a common format and interpreted jointly to describe the broad-scale climatic features of the ice sheet. Climatological results include (1) an absolute lowest minimum temperature of -84.6-degrees-C at Dome C; (2) no minimum below -40-degrees-C at D10 near the coast: (3) a ''coreless'' winter temperature regime, without seasonal temperature trends for 6 months, at all stations; (4) mean surface with speeds increasing to maxima near, rather than at, the coast; (5) high directional constancy in all seasons, with directions closer to the fall line in winter and during night hours than in summer and during day hours; (7) a distinct semiannual pressure variation with a main minimum in spring (September) and a secondary minimum in autumn (March); and (8) interrelationships among surface temperature, pressure, and wind related to the ice sheet topography.