Surface winds over the Antarctic continent: A review

摘要

Surface winds over Antarctica, often classified as “katabatic,” are intimately related to the orientation and steepness of the underlying ice terrain. Such flows result primarily from the strong radiational cooling of the sloping ice surface which creates a downslope‐directed horizontal pressure gradient force. It is possible to diagnose the time‐averaged, near‐surface streamline patterns of cold air drainage currents using recently compiled, detailed Antarctic ice topography maps and appropriate estimates of the strength of the surface temperature inversion. The resulting streamlines agree with available observations and illustrate the high degree of nonuniformity of gravity‐driven flows off the ice sheets. In certain interior sections, negatively buoyant air from a large catchment area drains through a restricted section of coastline. Such confluence zones represent regions of enhanced supplies of cold air and are shown to be related to anomalously strong katabatic winds. Implications for sea ice formation ar