Accelerated Thermokarst Formation in the McMurdo Dry Valleys, Antarctica
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...
| Main Authors: | , , , , , , |
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| Format: | Text |
| Language: | unknown |
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PDXScholar
2013
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| Subjects: | |
| Online Access: | https://pdxscholar.library.pdx.edu/geology_fac/40 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=1040&context=geology_fac |
| Summary: | 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. |
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