Accelerated thermokarst formation in the McMurdo Dry Valleys, Antarctica

• Published in: Scientific Reports
• Main Authors: Levy, Joseph S., Fountain, Andrew G., Dickson, James L., Head, James W., Okal, Marianne, Marchant, David R., Watters, Jaclyn
• Format: Text
• Language: English
• Published: Nature Publishing Group 2013
• Subjects: Article; Antarctic; Antarctic Peninsula; Arctic; Garwood; Garwood Valley; McMurdo Dry Valleys; The Antarctic; albedo; Antarc*; Antarctica; Thermokarst
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3721085; http://www.ncbi.nlm.nih.gov/pubmed/23881292; https://doi.org/10.1038/srep02269

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.