EVIDENCE FOR ACCELERATED SURFACE MELTING RATES ON THE LINNÉ GLACIER, SVALBARD

Responses of Arctic glaciers and surface lowering can provide a record of glacier mass balance and climate change. High resolution surface lowering, ablation stake, and local meteorological data from Linnébreen Glacier were collected during a twenty one day period during the 2006-2007 ablation year. Linnébreen is located on the Western edge of Spitsbergen, the largest island of the Svalbard archipelago. Ablation stakes located at eight centerlines of Linnébreen recorded surface lowering at eleven different time intervals over the twenty one day field season. Surface lowering and meteorological data; surface air temperature, precipitation, solar radiation, and relative humidity, were continuously recorded at 30 minute intervals from ablation stake two. Other records of meteorological data; surface air temperature, precipitation, and relative humidity were recorded approximately 6km down the glacial valley, on a terminal moraine at the LIA maximum, as well as on a lateral moraine near ablation stake seven. These high resolution surface lowering and ablation records were then correlated to meteorological observations. Continued observations of Linnébreen and its surface lowering driving processes will provide more evidence for rapid changes and related glacier response in the high Arctic. Over the period of 23 July to 12 August 2006, the largest surface lowering events were driven by rainfall events. Meteorological records from ablation stake two, as well as down valley show that surface air temperatures do not directly correspond to increased surface lowering; and the peak season temperature does not correspond with the greatest surface lowering response. Rainfall does, however, induce more rapid surface lowering rates, and is the main agent of seasonal ablation. In order to develop a statistical model to accurately estimate the relationships between these variables, Multiple Regression/Correlation (MRC) of surface lowering rates were calculated at each rainfall event. Results suggest that the precipitation events increased the surface lowering rates. Meteorological data within the Linné Valley for the past 3 years indicates that rainfall events have increased in frequency. Given this increase in rainfall events from the past 3 years, Linnébreen's melting rates reflect not only a seasonal change, but are more likely a response to climate change.