Mawson’s climate is typical of much of the coast of East Antarctica where the ice cap falls steeply to sea level. The main feature is the katabatic, or gravity wind. These winds happen when cold air moves down the steep slopes of the ice sheet from the high interior of the continent, picking up speed until they reach the coast.
Winds at Mawson mostly come from the east and south. The mean annual speed is 21 knots (almost 40 km/h). Sometimes, prolonged periods of strong winds occur averaging over 50 knots. Maximum gusts during these times often exceed 130 to 140 knots. Mean wind speed decreases as it gets closer to the seaward and further from the icecap. The cold air loses its speed across the fast ice or the sea off-shore.
Because it lies south of the Antarctic Circle, the sun does not rise at Mawson for approximately 6 weeks from the first week in June. It also does not set for 6 weeks from early December. During those 6 weeks in June and July, the day has only a few hours of twilight.
Tidal predictions
Tides are measured for many different research and operational reasons. These measurements have a practical value in working out sea level. They are used for mapping elevations and ocean depths, tidal predictions for shipping, and in the calibration of satellite altimeters.
Tide measurements also have a research value. Sea level data helps us understand long-term climate change as well as continental readjustment, heat transfer across the continental shelf, and other oceanographic phenomena including observation of Southern Ocean oscillation.