| Summary: | Abstract: Modern glacial process studies on Arctic glaciers provide valuable information on responses to climate change in high latitudes, and may also suggest eventual implications for lower latitudes. Most Arctic glaciers exist at higher air temperatures than Antarctic glaciers, and are thus likely to show a more rapid response to global climate change. Understanding factors that influence glacier mass balance and quantifying ablation dynamics provide useful data to document the Arctic’s response to changing climatic conditions. Research was conducted on Spitsbergen, the largest island of the Svalbard Archipelago in the Norwegian Arctic, and was supported by the National Science Foundation Research for Undergraduates program at Hampshire College. Glacier surface lowering, meltwater discharge, and meteorological conditions were monitored during the 2008 summer melt season at Linnébreen, an Arctic cirque glacier. Nine glacier surface lowering measurements were taken at eight centerline locations over the course of the 2008 ablation season (mid-July through mid-August). These measurements were correlated to meteorological observations to better understand surface lowering dynamics of the glacier. Snow loss from Linnébreen was converted to a meltwater equivalent to estimate the volume of water lost from the glacier for each day. This volume was then compared to measured discharge in the adjacent meltwater stream. The highest ablation occurred during late July 2008, corresponding to periods of higher temperature and solar radiation. These 2008 results are consistent with historical records. Photo analysis reveals an average glacier retreat rate of 17 m/yr since 1936 with a rate of 41 m/yr during the past 14 years. Measurements indicate average surface lowering of 1.13 meters for the 2008 melt season, and a negative net balance of 0.34 meters, less negative than most years. Melting due to high temperature and direct sunlight are inferred to be the main agents of surface lowering of Linnébreen. Continued observation is essential to better evaluate the controls on surface lowering and negative mass balance of Linnébreen. The glacial mass loss at Linnébreen is consistent with other proxy climate records in the High Arctic, which indicate accelerated warming in this region.
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