Changes in lake drainage in the western Canadian Arctic

• Main Authors: Kariyawasam, Dilshan, Marsh, Philip, Dr
• Format: Text
• Language: English
• Published: Scholars Commons @ Laurier 2022
• Subjects: lake change; lake drainage; thermokarst; remote sensing; Mackenzie delta uplands; permafrost; Climate; Fresh Water Studies; Arctic; Inuvik; Mackenzie Delta; Tuktoyaktuk; Thermokarst
• Online Access: https://scholars.wlu.ca/etd/2458; https://scholars.wlu.ca/cgi/viewcontent.cgi?article=3601&context=etd

Nearly half of all Pan-Arctic lakes are situated in the Canadian Arctic, with many of these lakes being of thermokarst origin. Thermokarst lakes are sensitive to changes in the surrounding environment, making them useful indicators to examine the condition of hydrological systems in response to rapid climate warming, a trend which has been well observed in the Canadian Western Arctic. In this study, we use aerial photography to quantify lake area and count changes for lakes in the Inuvik-Tuktoyaktuk region, between 1950 and 2004. A combination of aerial photography and Landsat imagery were used in identifying drained thermokarst lake basins (DTLBs) between 1950 and 2019. In addition, we investigated the spatial relationship of DTLBs to surficial geology between 1950 and 2019. Comparing digitized datasets for 1950 and 2004, lakes decreased in number and increased in size. Associating DTLBs with an approximate time of drainage has indicated that the rate of lake drainage has increased dramatically in recent years. Kernel density estimation conducted on DTLB points revealed that there are several clusters where drained lakes have occurred. Further analysis revealed that most drained lake events occur on moraine sediments, with a disproportionate number of lake drainage events occurring on hummocky rolling moraine soils. With the establishment of long-term lake observations from our DTLB and digitized lake data, we demonstrate how lakes are responding to climate warming, revealing spatial and temporal correspondence of thermokarst development across the Inuvik-Tuktoyaktuk region.