Remote sensing for snow cover analysis along the Drakensberg escarpment

THE EXTENT TO WHICH THE DRAKENSBERG escarpment affects snow cover distribution was examined over a latitudinal distance of 93 km, from Champagne Castle to the lower Leqooa River Valley. The analysis was undertaken with the use of Landsat 5 Thematic Mapper imagery, which dates from 31 May 1996, seven days after a snow-producing cold front crossed the region. Factors such as latitude, topographic orientation and westerly distance from the, escarpment edge were examined for their influence on snow distribution. Areas north of 29degrees20'S (Giant's Castle), hosted fewer snow patches than those to the south. A strong negative correlation was found between area of snow cover and westerly distance from the escarpment. Snow cover was restricted to south-facing (90-270degrees) slopes after one week of ablation. We argue that the topography of the Drakensberg escarpment has a primary function in controlling snow cover. Analysis of contemporary snow patch distribution may contribute to an understanding of the origins of palaeogeomorphic phenomena along the Drakensberg.