Wind in Antarctica
The BAS stations generally experience moderate winds, with mean wind speeds of around 6 ms-1 (12 kt, moderate breeze), but in gales, which can occur on over 40 days a year, mean speeds can exceed 30 ms-1 (60 kt, violent storm) with gusts of over 40 ms-1 (80 kt). Signy is the windiest BAS station and has experienced hurricane force gusts over 55 ms-1 (110 kt).
Elsewhere, strong katabatic winds, caused by the flow of cold air off the plateau, make some coastal sites around Antarctica the windiest places in the world.
Port Martin (67°S 141°E) is an especially windy site with an annual mean wind speed of 17 ms-1 (33 kt — nearly gale force). The station has recorded a monthly mean wind speed of 28 ms-1 (54 kt — storm force 10) and a daily mean of 46 ms-1 (89 kt). On average it has only 22 days a year with mean wind speeds less than 13 ms-1 (25 kt).
Winds at the South Pole are mostly controlled by the slope of the snow surface and are a relatively uniform 6 ms-1 (12 kt) from a direction of longitude 22° East. There are few calms or gales.