The 5th Conference on Polar Meteorology and Oceanography

12.6
ON THE SASTRUGI FORMATION IN ADELIE LAND, EASTERN ANTARCTICA

M Mattes, Swiss Federal Inst. of Technology, Zürich, Switzerland; and J. Kelley and G. Wendler

On 12 December 1985, vertical photographs of the sastrugi structure were taken during a flight from Dome C (3280 m asl) to Dumont d'Urville (43 m asl), Eastern Antarctica, a distance of 1080 km. The camera (9" by 9") was located in the belly of an LC 130 aircraft, and the flight altitude was kept at the nominal height of 150 m above ground; 67 photos were taken. Below the flight path, six automatic weather stations (AWS) had been placed, hence surface climatological data, including wind speed and direction, are available. We digitized 6 of the photographs, so that quantitative information on the sastrugi could be obtained. Some of the findings are:

* At Dome C, three dominant sastrugi directions could be observed, while in the coastal area there was only one. Surface observations show that the wind directional constancy is low on the high plateau, while it is high in the coastal regions.

* The sastrugi directions agreed well with the observed wind directions, both for the coastal area as for the high plateau.

* When flying over the continental slope towards the coast, the sastrugi become more numerous, their average length increased and their directions became much more uniform.

* The largest sastrugi were found about 150 - 200 km from the edge of the continent in an area, where the slope angle was relatively steep.

The 5th Conference on Polar Meteorology and Oceanography