LONG-TERM INTEGRATED BASIN MONITORING OF A SVALBARD ARCTIC GLACIER-RIVER LAKE SYSTEM: INITIAL RESULTS

The Svalbard archipelago, between 74° and 81° N latitude in the north Atlantic, lies at the northern end of the warm Gulf Stream current and therefore is sensitive to subtle climate and oceanographic changes. As part of a three-year NSF funded REU project, we are monitoring modern climatological, glaciological, hydrological, and sedimentological processes operating in the Linné Valley to improve Holocene climate reconstructions based on sediment cores recovered from Lake Linné.

Our team of undergraduate students initiated a basin-wide analysis of the glacier-river-lake sedimentary system in 2004. Linné Valley weather records are being compared with other records to match local weather events to synoptic patterns. We initiated long-term mass balance monitoring of the Linné Glacier - during the 2004 season ablation was extensive with a net loss of 1.21m water equivalent. During Holocene time, the Linné Glacier advanced and retreated in response to climate change and mobilized distinctive sediment lithologies. Sediment samples from tributary streams and the lake are being analyzed to determine if sediment provenance can be used as a proxy of past glacial activity. Meltwater discharge fluctuations from the glacier control delivery of sediments to the lake. We directly measured discharge on a daily basis and an automatic stage gage provides a 30 minute resolution record of discharge which can be correlated to precipitation and solar energy intensity to determine the major controls on glacier ablation and meltwater volume. At the mouth of the inlet stream, sediment traps were installed to measure sediment delivery – large fluctuations of sediment were observed before and after intense rain storms, although sedimentation was spatially and temporally variable. Sediment distribution within the lake is controlled by lake water stratification and currents. We monitored temperature at multiple depths throughout the lake with self-contained temperature loggers supplemented with continuous CTD casts measuring temperature and turbidity. Finally, short sediment cores from the lake reveal very fine laminations that we believe can be attributed to the climate, weather, and sedimentary processes we are monitoring.