| Summary: | The purpose of this project is to characterize the physical processes in Lake Linne, Spitsbergen Island, Svalbard, that lead to heterogeneous water temperatures during the high arctic summer. When adequately defined, this lake can be used in studies of global warming effects in high arctic lakes. We analyzed available atmospheric and lake temperature data for the period of July 31 through September 4,2003. For July 31 through August 19, surface water temperatures increased from 4°C to 7°C, and then fell to 5.8°C at the end of the observational period. This trend corresponds to concomitant air temperature changes. The increase lags shortly behind warm southerly weather while the cooling trend follows weak northerly winds. Anomalies in water temperature trends correspond to an unsettled time of variable wind azimuth. Thermal stratification in shallow water is lost during periods of strong southerly wind in response to an upwelling event. Our observations indicate that air temperature is the dominant control on water temperature at shelf and open water sites through ten meters of water depth. However, strong southerly winds can cause vertical and horizontal changes in water temperature through upwelling, and lateral displacement of surface water. Thus, our single-season data indicate that lake water temperatures are proxies of atmospheric temperature although strong winds perturb the system.
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