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Snowmelt is a crucial source of water for many shallow subarctic lakes, but climate models predict that snowfall will decrease in some regions, with profound ecological consequences. Here we use lake water isotope data across gradients of terrestrial vegetation cover (open tundra to closed forest) and topographic relief to identify lakes that are vulnerable to desiccation under conditions of low snowmelt runoff in two subarctic landscapes?Old Crow Flats, Yukon, and Hudson Bay Lowlands, Manitoba (Canada). Lakes located in low-relief, open tundra catchments in both landscapes displayed a systematic, positive offset between directly measured lake water ?18O over multiple sampling campaigns and lake water ?18O inferred...
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Growing evidence indicates that lake-dominated ecosystems at high latitudes are undergoing significant hydrological changes. Research examining these changes is complicated because both thermokarst and climatic processes likely influence lake dynamics. To examine the relative impacts these processes in permafrost landscapes we investigated the dynamics of lake area and number in Old Crow Flats (OCF) using historical air photos and satelite imagery. Between 1951 and 2007, the OCF experienced a decline of ~6000 ha in total lake area, but gained 232 lakes. Close to half (49%) of the difference in lake area was driven by the rapid and persistent drainage of 38 large lakes. These catastrophic drainages were associated...
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Growing evidence indicates that lake-dominated ecosystems at high latitudes are undergoing significant hydrological changes. Research examining these changes is complicated because both thermokarst and climatic processes likely influence lake dynamics. To examine the relative impacts these processes in permafrost landscapes we investigated the dynamics of lake area and number in Old Crow Flats (OCF) using historical air photos and satelite imagery. Between 1951 and 2007, the OCF experienced a decline of ~6000 ha in total lake area, but gained 232 lakes. Close to half (49%) of the difference in lake area was driven by the rapid and persistent drainage of 38 large lakes. These catastrophic drainages were associated...
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Growing evidence indicates that lake-dominated ecosystems at high latitudes are undergoing significant hydrological changes. Research examining these changes is complicated because both thermokarst and climatic processes likely influence lake dynamics. To examine the relative impacts these processes in permafrost landscapes we investigated the dynamics of lake area and number in Old Crow Flats (OCF) using historical air photos and satelite imagery. Between 1951 and 2007, the OCF experienced a decline of ~6000 ha in total lake area, but gained 232 lakes. Close to half (49%) of the difference in lake area was driven by the rapid and persistent drainage of 38 large lakes. These catastrophic drainages were associated...
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Growing evidence indicates that lake-dominated ecosystems at high latitudes are undergoing significant hydrological changes. Research examining these changes is complicated because both thermokarst and climatic processes likely influence lake dynamics. To examine the relative impacts these processes in permafrost landscapes we investigated the dynamics of lake area and number in Old Crow Flats (OCF) using historical air photos and satelite imagery. Between 1951 and 2007, the OCF experienced a decline of ~6000 ha in total lake area, but gained 232 lakes. Close to half (49%) of the difference in lake area was driven by the rapid and persistent drainage of 38 large lakes. These catastrophic drainages were associated...
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