Evolution of supra-glacial lakes across the Greenland ice sheet
dc.contributor.advisor
Shepherd, Andrew
en
dc.contributor.advisor
Nienow, Pete
en
dc.contributor.author
Sundal, Aud
en
dc.date.accessioned
2008-08-20T10:04:16Z
dc.date.available
2008-08-20T10:04:16Z
dc.date.issued
2008-12-05
dc.description.abstract
We used 268 cloud-free Moderate-resolution Imaging Spectroradiometer (MODIS) images spanning the melt seasons 2003 and 2005-2007 to study the seasonal evolution of supra-glacial lakes in three different regions of the Greenland ice sheet. Lake area estimates were obtained by developing an automated classification method for their identification based on 250 m resolution MODIS surface reflectance data. Widespread supra-glacial lake formation and drainage are observed across the ice sheet, with a 2-3 weeks delay in the evolution of total supra-glacial lake area in the northern areas compared to the south-west. The onset of lake growth varies by up to one month inter-annually, and lakes form and drain at progressively higher altitudes during the melt season. The annual peak in total lake area is positively correlated with modelled annual runoff across all study areas, suggesting that local runoff governs seasonal variations in total supra-glacial lake area. Our results indicate that, in a future warmer climate (Meehl et al 2007), Greenland supra-glacial lakes can be expected to form at higher altitudes and over a longer time period than is presently the case, expanding the area and time period over which connections between the ice sheet surface and base may be established (Das et al 2008) and thereby potentially increasing ice sheet discharge (Zwally et al 2002).
en
dc.format.extent
24573 bytes
en
dc.format.extent
1757653 bytes
en
dc.format.extent
326455 bytes
en
dc.format.mimetype
application/pdf
en
dc.format.mimetype
application/pdf
en
dc.format.mimetype
application/pdf
en
dc.identifier.uri
http://hdl.handle.net/1842/2454
dc.language.iso
en
dc.subject
MODIS
en
dc.subject
supra-glacial lakes
en
dc.subject
Greenland
en
dc.subject
image classification
en
dc.subject
GIS
en
dc.subject
MSc Geographical Information Science
en
dc.title
Evolution of supra-glacial lakes across the Greenland ice sheet
en
dc.type
Thesis or Dissertation
en
dc.type.qualificationlevel
Masters
en
dc.type.qualificationname
MSc Master of Science
en
dcterms.accessRights
RESTRICTED ACCESS
en
Files
This item appears in the following Collection(s)