Changes in the cliff face (retreat) at a cold based glacier, Wright Lower Glacier, Wright Valley, Antarctica

A change in the position of the supraglacial channel cliff faces of the Wright Lower Glacier was investigated over three field seasons (04-05, 05-06 and 06-07). The volume of ice lost due to cliff retreat was estimated by setting up ablation markers in the front of the cliff (= baseline measurements). At four cross sections, a tape was set up between the markers and at set intervals the distance to the cliff and height of the cliff was measured approx every 10 days. This set up was established in the first season and subsequently measured in the following seasons. As a alternative to these measurements, two markers were placed on the top of the cliff from which distance to the cliff was recorded. A change in the morphology of the supraglacial channel was also measured at four cross sections using a dumpy level.