This work was supported by the U.S. National Science Foundation (NSF) Antarctic Earth Sciences program under award ANT-1343835 to Levy, Fountain, and W. B. Lyons.
Thermokarst -- Growth -- Antarctica -- McMurdo Dry Valleys, Glacier caves, Landscape changes -- Antarctica, Glaciers -- Climatic factors -- Arctic regions
Thermokarst is a land surface lowered and disrupted by melting ground ice. Thermokarst is a major driver of landscape change in the Arctic, but has been considered to be a minor process in Antarctica. Here, we use ground-based and airborne LiDAR coupled with timelapse imaging and meteorological data to show that 1) thermokarst formation has accelerated in Garwood Valley, Antarctica; 2) the rate of thermokarst erosion is presently,10 times the average Holocene rate; and 3) the increased rate of thermokarst formation is driven most strongly by increasing insolation and sediment/albedo feedbacks. This suggests that sediment enhancement of insolation-driven melting may act similarly to expected increases in Antarctic air temperature (presently occurring along the Antarctic Peninsula), and may serve as a leading indicator of imminent landscape change in Antarctica that will generate thermokarst landforms similar to those in Arctic periglacial terrains.
Levy, J.S.et al. Accelerated thermokarst formation in the McMurdo Dry Valleys, Antarctica. Sci. Rep. 3, 2269; DOI:10.1038/srep02269 (2013).