Surface climate of the interior of the Lambert Glacier basin, Antarctica, from automatic weather station data

Abstract

Data from six automatic weather stations deployed around the interior of the Lambert Glacier basin, Antarctica, at surface elevations of 1830-2741 m are used to compile a surface climatology of this part of interior Antarctica for the period 1994-96. The stations measure air pressure, near-surface wind speed and air temperature at several levels, wind direction and firn temperatures. The topography of the basin, which extends more than 800 km inland, controls the katabatic wind regime and strongly influences the surface climate of the region. Windiest sites are on the steep coastal slopes, and within the depression of the Lambert and Mellor Ice Streams where the flow is topographically channelled. Surface winds here show greater seasonal variation in speed but less variation in direction than elsewhere. The annual mean temperatures on the relatively steep slopes on the eastern side of the basin are 4-5°C warmer than at equivalent altitude on the western side. During winter, near-synchronous synoptic temperature and pressure increases occur throughout the basin to at least 1000 km from the coast. There is a consistent pattern of diurnal wind variation in the summer at all stations, with maximum wind speed at about 0900 LST (local solar time), and the most easterly direction at 1300 LST.