Thompson, SS and Benn, DI and Dennis, K and Luckman, A, A rapidly growing moraine-dammed glacial lake on Ngozumpa Glacier, Nepal, Geomorphology, 145-146 pp. 1-11. ISSN 0169-555X (2012) [Refereed Article]
Copyright 2011 Elsevier B.V.
Moraine-dammed glacial lakes are becoming increasingly common in the Himalaya as a result of glacier mass loss, causing concern about glacier lake outburst flood risk. In addition to extant lakes, the potential exists for many more to form, as more glaciers ablate down to the level of potential moraine dams. In this paper, we document the recent rapid growth of, a moraine-dammed lake on Ngozumpa Glacier, Nepal. Using a combination of ground-based mapping and sonar surveys, aerial photographs (< 1 m resolution), and ASTER imagery (15 m resolution), processes and rates of lake expansion have been determined. The lake first formed between 1984 and 1992 when collapse of an englacial conduit allowed water to accumulate at the level of a gap in the lateral moraine, ~km from the glacier terminus. Lake growth was initially slow, but since 2001 it has undergone exponential growth at an average rate of 10% y−1. In 2009, the lake area was 300,000 m2, and its volume was at least 2.2 million m3. Calving, subaqueous melting, and melting of subaerial ice faces all contribute to the expansion of the lake; but large-scale, full-height slab calving is now the dominant contributor to growth. Comparison with other lakes in the region indicate that lake growth will likely continue unchecked whilst the spillway remains at its current level and may attain a volume of hundreds of millions of cubic metres within the next few decades.
|Item Type:||Refereed Article|
|Keywords:||glacier, glacial lake outburst flood, hazard, Himalayas|
|Research Division:||Earth Sciences|
|Research Group:||Physical geography and environmental geoscience|
|Objective Division:||Environmental Policy, Climate Change and Natural Hazards|
|Objective Group:||Mitigation of climate change|
|Objective Field:||Climate change mitigation strategies|
|UTAS Author:||Thompson, SS (Dr Sarah Thompson)|
|Web of Science® Times Cited:||64|
|Deposited By:||Australian Antarctic Program Partnership|
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