Assessing Supraglacial Water Volume and the Changing Dynamics of the Surface Topography Near the Jakobshavn Glacier, Greenland
On the Greenland Ice Sheet (GIS), the effect of the melt season’s changing supraglacial lakes on outlet glacier discharge is not well understood. It is known that many supraglacial lakes drain rapidly during each melt season. While there are conflicting theories of the significance of supraglacial l...
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ftunicolboulder:oai:scholar.colorado.edu:geog_gradetds-1009 2023-05-15T13:11:48+02:00 Assessing Supraglacial Water Volume and the Changing Dynamics of the Surface Topography Near the Jakobshavn Glacier, Greenland Adler, John 2010-01-01T08:00:00Z application/pdf https://scholar.colorado.edu/geog_gradetds/12 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=1009&context=geog_gradetds unknown CU Scholar https://scholar.colorado.edu/geog_gradetds/12 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=1009&context=geog_gradetds Geography Graduate Theses & Dissertations Greenland Ice Sheet Supraglacial Lakes UAS UAV Climate Environmental Indicators and Impact Assessment Environmental Monitoring text 2010 ftunicolboulder 2018-10-07T08:47:01Z On the Greenland Ice Sheet (GIS), the effect of the melt season’s changing supraglacial lakes on outlet glacier discharge is not well understood. It is known that many supraglacial lakes drain rapidly during each melt season. While there are conflicting theories of the significance of supraglacial lake drainages towards enhancing ice sheet flow, it is highly important to quantify the actual water volume of supraglacial lakes since their drainage via crevasses or moulins enables the injection of melt water directly into the GIS. The 2008 Arctic MUltiSensor Cryospheric Observation eXperiment (Arctic MUSCOX) was the first scientific Unmanned Aircraft System (UAS) used in Greenland. The goal was determination of the changing volumes of supraglacial melt water lakes through the fusion of disparate data sets from in--‐situ, airborne, and satellite sensors. Near the Jakobshavn Isbrae region, four supraglacial lakes at different elevations along a transect at 68.73°N were monitored over the 2006, 2007, and 2008 melt seasons. The changing lake volumes are calculated for each day of usable MODIS imagery, employing DEM’s from both ASTER Global and the MUSCOX lidar survey. During this three year period, no observed lake was larger in volume than 0.15km3, or larger in area than 10.4km2, implying a size limit for supraglacial lakes. In this study a new technique is developed calculating runoff using daily changing albedo and surface height measurements (dH) from the Greenland Climatic Network (GC--‐ Net) Automatic Weather Stations (AWS) at locations JAR1 and JAR2. Runoff is calculated on a daily basis, both regionally and for a 1,183km2 inset strip straddling the transect. At JAR1 the calculated linear runoff for 2006, 2007, and 2008 is 1.79m, 1.99m, and 1.96m, respectively; at JAR2 the calculated runoff is 2.11m, 2.86m, and 2.40m, respectively. Regional projections are made that account for future atmospheric temperature increases between 0.5°C and 3.0°C; they indicate up to a 43.3% increase in the area available for the formation of supraglacial lakes in the GIS. Finally, a proposal is presented to obtain scientific measurements of Arctic Key Parameters (AKP’s) in the region’s data sparse areas via UAS through the cooperation of the international community. Text albedo Arctic glacier Greenland Ice Sheet Jakobshavn University of Colorado, Boulder: CU Scholar Arctic Greenland Changing Lake ENVELOPE(-45.619,-45.619,-60.708,-60.708) |
institution |
Open Polar |
collection |
University of Colorado, Boulder: CU Scholar |
op_collection_id |
ftunicolboulder |
language |
unknown |
topic |
Greenland Ice Sheet Supraglacial Lakes UAS UAV Climate Environmental Indicators and Impact Assessment Environmental Monitoring |
spellingShingle |
Greenland Ice Sheet Supraglacial Lakes UAS UAV Climate Environmental Indicators and Impact Assessment Environmental Monitoring Adler, John Assessing Supraglacial Water Volume and the Changing Dynamics of the Surface Topography Near the Jakobshavn Glacier, Greenland |
topic_facet |
Greenland Ice Sheet Supraglacial Lakes UAS UAV Climate Environmental Indicators and Impact Assessment Environmental Monitoring |
description |
On the Greenland Ice Sheet (GIS), the effect of the melt season’s changing supraglacial lakes on outlet glacier discharge is not well understood. It is known that many supraglacial lakes drain rapidly during each melt season. While there are conflicting theories of the significance of supraglacial lake drainages towards enhancing ice sheet flow, it is highly important to quantify the actual water volume of supraglacial lakes since their drainage via crevasses or moulins enables the injection of melt water directly into the GIS. The 2008 Arctic MUltiSensor Cryospheric Observation eXperiment (Arctic MUSCOX) was the first scientific Unmanned Aircraft System (UAS) used in Greenland. The goal was determination of the changing volumes of supraglacial melt water lakes through the fusion of disparate data sets from in--‐situ, airborne, and satellite sensors. Near the Jakobshavn Isbrae region, four supraglacial lakes at different elevations along a transect at 68.73°N were monitored over the 2006, 2007, and 2008 melt seasons. The changing lake volumes are calculated for each day of usable MODIS imagery, employing DEM’s from both ASTER Global and the MUSCOX lidar survey. During this three year period, no observed lake was larger in volume than 0.15km3, or larger in area than 10.4km2, implying a size limit for supraglacial lakes. In this study a new technique is developed calculating runoff using daily changing albedo and surface height measurements (dH) from the Greenland Climatic Network (GC--‐ Net) Automatic Weather Stations (AWS) at locations JAR1 and JAR2. Runoff is calculated on a daily basis, both regionally and for a 1,183km2 inset strip straddling the transect. At JAR1 the calculated linear runoff for 2006, 2007, and 2008 is 1.79m, 1.99m, and 1.96m, respectively; at JAR2 the calculated runoff is 2.11m, 2.86m, and 2.40m, respectively. Regional projections are made that account for future atmospheric temperature increases between 0.5°C and 3.0°C; they indicate up to a 43.3% increase in the area available for the formation of supraglacial lakes in the GIS. Finally, a proposal is presented to obtain scientific measurements of Arctic Key Parameters (AKP’s) in the region’s data sparse areas via UAS through the cooperation of the international community. |
format |
Text |
author |
Adler, John |
author_facet |
Adler, John |
author_sort |
Adler, John |
title |
Assessing Supraglacial Water Volume and the Changing Dynamics of the Surface Topography Near the Jakobshavn Glacier, Greenland |
title_short |
Assessing Supraglacial Water Volume and the Changing Dynamics of the Surface Topography Near the Jakobshavn Glacier, Greenland |
title_full |
Assessing Supraglacial Water Volume and the Changing Dynamics of the Surface Topography Near the Jakobshavn Glacier, Greenland |
title_fullStr |
Assessing Supraglacial Water Volume and the Changing Dynamics of the Surface Topography Near the Jakobshavn Glacier, Greenland |
title_full_unstemmed |
Assessing Supraglacial Water Volume and the Changing Dynamics of the Surface Topography Near the Jakobshavn Glacier, Greenland |
title_sort |
assessing supraglacial water volume and the changing dynamics of the surface topography near the jakobshavn glacier, greenland |
publisher |
CU Scholar |
publishDate |
2010 |
url |
https://scholar.colorado.edu/geog_gradetds/12 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=1009&context=geog_gradetds |
long_lat |
ENVELOPE(-45.619,-45.619,-60.708,-60.708) |
geographic |
Arctic Greenland Changing Lake |
geographic_facet |
Arctic Greenland Changing Lake |
genre |
albedo Arctic glacier Greenland Ice Sheet Jakobshavn |
genre_facet |
albedo Arctic glacier Greenland Ice Sheet Jakobshavn |
op_source |
Geography Graduate Theses & Dissertations |
op_relation |
https://scholar.colorado.edu/geog_gradetds/12 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=1009&context=geog_gradetds |
_version_ |
1766249071862874112 |