This interdisciplinary and international project has recently been initiated mainly with IPY fund... more This interdisciplinary and international project has recently been initiated mainly with IPY funding from Denmark and Greenland. In short the project investigates the linkage between ice sheet freshwater release to a fiord near Nuuk (South-western Greenland) and the resulting fiord circulation. The low density melt water draining into the innermost of the long fiord forms a brackish outward sloping top layer, which exits the fiord and is balanced by entrance of nutritious salty oceanic water below. Such nutritious water, in turn, favors marine production in the fiord. The perspectives of a warmer climate, where more ice sheet melt water will increase the marine production, is of vital interest to investigate for the Greenland society because the present export from the country is totally dominated by living resources of the oceans. This interdisciplinary research project involves scientists from Greenland, Norway, Denmark and USA. Scientific disciplines presently covered are; marine...
The glacier surface albedo is important for ice melt. Studies have revealed that even small chang... more The glacier surface albedo is important for ice melt. Studies have revealed that even small changes in the surface albedo often have significant impact on the resulting ice melt. For instance a 15% reduction in surface reflectance on the Greenland ice sheet is sufficient to cause over one meter annual excess ice melt, which is the magnitude of present thinning may places on the Greenland ice sheet margin. Except for minor areas around Nunataks as well as moraine material the surface the particulate matter (PM) constitutes of aerosols accumulated on the glacier surface for hundreds or thousands of years. In PM on the glacier surface a significant biological activity exists due to abundance of algae, bacteria and other micro- organisms. The biological activity is able to effectively bind particles to the biomass in so-called "cryoconite". The result is a favourable substrate for bacterial activity, which "flocculate" the micro particles and thus affects the glacier...
Page 1. The microstructure and biogeochemistry of Arctic cryoconite granules Harry LANGFORD,1,2 A... more Page 1. The microstructure and biogeochemistry of Arctic cryoconite granules Harry LANGFORD,1,2 Andy HODSON,1 Steve BANWART,2 Carl BØGGILD3 1Department of Geography, University of Sheffield, Winter Street, Sheffield ...
... The second set consists of a bedrock elevation model acquired with an airborne 60 MHz ice-rad... more ... The second set consists of a bedrock elevation model acquired with an airborne 60 MHz ice-radar system on a Twin Otter aircraft described in Christensen and others (2000), and a DEM derived from repeat-track synthetic aperture radar interferometry (InSAR) and resampled to ...
A distributed energy-balance model was forced with albedo derived from the Advanced Very High Res... more A distributed energy-balance model was forced with albedo derived from the Advanced Very High Resolution Radiometer (AVHRR) Polar Pathfinder (APP) data to evaluate the common assumption that ice sheet ablation can be considered a simple function of elevation. The model was applied to the western margin of the Greenland Ice Sheet between 67oN and 65o30'N because of the spatial heterogeneity of this area. Meteorological and glaciological observations from two transects were used to estimate input parameters and test the model, respectively. The ablation was found to be highly variable near the ice margin irrespective of elevation, indicating that ice margin proximity may be important for simple ablation parameterizations. A better correlation between ablation and elevation was found above the equilibrium-line altitude. The APP albedo was compared to in situ albedo measurements near the ice margin and found to be in good agreement, with a mean difference between the in situ albedo ...
This interdisciplinary and international project has recently been initiated mainly with IPY fund... more This interdisciplinary and international project has recently been initiated mainly with IPY funding from Denmark and Greenland. In short the project investigates the linkage between ice sheet freshwater release to a fiord near Nuuk (South-western Greenland) and the resulting fiord circulation. The low density melt water draining into the innermost of the long fiord forms a brackish outward sloping top layer, which exits the fiord and is balanced by entrance of nutritious salty oceanic water below. Such nutritious water, in turn, favors marine production in the fiord. The perspectives of a warmer climate, where more ice sheet melt water will increase the marine production, is of vital interest to investigate for the Greenland society because the present export from the country is totally dominated by living resources of the oceans. This interdisciplinary research project involves scientists from Greenland, Norway, Denmark and USA. Scientific disciplines presently covered are; marine...
The glacier surface albedo is important for ice melt. Studies have revealed that even small chang... more The glacier surface albedo is important for ice melt. Studies have revealed that even small changes in the surface albedo often have significant impact on the resulting ice melt. For instance a 15% reduction in surface reflectance on the Greenland ice sheet is sufficient to cause over one meter annual excess ice melt, which is the magnitude of present thinning may places on the Greenland ice sheet margin. Except for minor areas around Nunataks as well as moraine material the surface the particulate matter (PM) constitutes of aerosols accumulated on the glacier surface for hundreds or thousands of years. In PM on the glacier surface a significant biological activity exists due to abundance of algae, bacteria and other micro- organisms. The biological activity is able to effectively bind particles to the biomass in so-called "cryoconite". The result is a favourable substrate for bacterial activity, which "flocculate" the micro particles and thus affects the glacier...
Page 1. The microstructure and biogeochemistry of Arctic cryoconite granules Harry LANGFORD,1,2 A... more Page 1. The microstructure and biogeochemistry of Arctic cryoconite granules Harry LANGFORD,1,2 Andy HODSON,1 Steve BANWART,2 Carl BØGGILD3 1Department of Geography, University of Sheffield, Winter Street, Sheffield ...
... The second set consists of a bedrock elevation model acquired with an airborne 60 MHz ice-rad... more ... The second set consists of a bedrock elevation model acquired with an airborne 60 MHz ice-radar system on a Twin Otter aircraft described in Christensen and others (2000), and a DEM derived from repeat-track synthetic aperture radar interferometry (InSAR) and resampled to ...
A distributed energy-balance model was forced with albedo derived from the Advanced Very High Res... more A distributed energy-balance model was forced with albedo derived from the Advanced Very High Resolution Radiometer (AVHRR) Polar Pathfinder (APP) data to evaluate the common assumption that ice sheet ablation can be considered a simple function of elevation. The model was applied to the western margin of the Greenland Ice Sheet between 67oN and 65o30'N because of the spatial heterogeneity of this area. Meteorological and glaciological observations from two transects were used to estimate input parameters and test the model, respectively. The ablation was found to be highly variable near the ice margin irrespective of elevation, indicating that ice margin proximity may be important for simple ablation parameterizations. A better correlation between ablation and elevation was found above the equilibrium-line altitude. The APP albedo was compared to in situ albedo measurements near the ice margin and found to be in good agreement, with a mean difference between the in situ albedo ...
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