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: Article in Journal/Newspaper
• Language: English
• Published: Nature Publishing Group 2013
• Subjects: Antarctic; Antarctic Peninsula; Arctic; Garwood; Garwood Valley; McMurdo Dry Valleys; The Antarctic; albedo; Antarc*; Antarctica; Thermokarst
• Online Access: https://authors.library.caltech.edu/72463/; https://authors.library.caltech.edu/72463/1/srep02269.pdf; https://authors.library.caltech.edu/72463/2/srep02269-s1.pdf; https://authors.library.caltech.edu/72463/3/srep02269-s2.mov; https://authors.library.caltech.edu/72463/4/srep02269-s3.mov; https://authors.library.caltech.edu/72463/5/srep02269-s4.mov; https://resolver.caltech.edu/CaltechAUTHORS:20161130-142502164

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.