2005: A look at the surfacebased temperature inversion over the Antarctic Plateau

Data from radiosondes, towers, and a thermistor string are used to characterize the temperature inversion at two stations: the Amundsen-Scott Station at the South Pole, and the somewhat higher and colder Dome C Station at a lower latitude. Ten years of temperature data from a 22-m tower at the South Pole are analyzed. The data include 2- and 22-m temperatures for the entire period and 13-m temperatures for the last 2 yr. Statistics of the individual temperatures and the differences among the three levels are presented for summer (December and Janu-ary) and winter (April–September). The relationships of temperature and inversion strength in the lowest 22 m with wind speed and down-ward longwave flux are examined for the winter months. Two preferred regimes, one warming and one cooling, are found in the temperature versus longwave flux data, but the physical causes of these regimes have not been determined. The minimum temperatures and the maximum inversions tend to occur not with calm winds, but with winds of 3–5 m s1, likely due to the inversion wind. This inversion wind also explains why the near-surface winds at South Pole blow almost exclusively from the northeast quadrant. Temperature data from the surface to 2 m above the surface from South Pole in the winter of 2001 ar