Authors: Box, Jason E.; Ski, Kathleen

Source: Journal of Glaciology, Volume 53, Number 181, March 2007 , pp. 257-265(9)

Publisher: International Glaciological Society

Abstract:

A supraglacial lake-depth retrieval function is developed, based on the correspondence between moderate-resolution imaging spectroradiometer (MODIS) reflectance and water depth measured during raft surveys. Individual lake depth, area and volume statistics, including short-term temporal changes for Greenland's southwestern ablation region, were compiled for 2000-05. The maximum area of an individual lake was found to be 8.9 km², the maximum volume 53.0 × 10⁶ m³ and the maximum depth 12.2 m, sampling over 0.0625 km² pixel areas. The total lake volume reaches >1 km³ in this region by July each year. The importance of melt lake reservoirs to Greenland ice-sheet flow may be a feedback between abrupt lake drainage events and ice dynamics. Lake-outburst volumes up to 31.5 ×10⁶ m³ d^-1 are capable of providing sufficient water via moulins to hydraulically pressurize the subglacial environment. Since the overburden pressure at the base of a flooded moulin is greater than that provided by ice, lake-outburst events seem capable of exerting sufficient upward force to lift the ice sheet locally, if water flow in the subglacial environment is constrained laterally. Considering a moulin with a 10 m² cross-sectional area, basal pressurization can be maintained over lake-outburst episodes lasting hours to days.

Document Type: Research article

DOI: http://dx.doi.org/10.3189/172756507782202883

Publication date: 2007-03-01

More about this publication?

• The Journal of Glaciology is published six times per year. It accepts submissions from any discipline related to the study of snow and ice. All articles are peer reviewed. The Journal is included in the ISI Science Citation Index.
• Editorial Board
• Information for Authors
• ingentaconnect is not responsible for the content or availability of external websites

Related content

• In this: publication
• By this: publisher
• In this Subject: Geology ,  Meteorology & Climatology
• By this author: Box, Jason E. ;  Ski, Kathleen

Website © Publishing Technology. Article copyright remains with the publisher, society or author(s) as specified within the article.

• Terms and conditions
• Privacy policy
• Information for advertisers