Four decades of lake surface temperature in the Northwest Territories, Canada, using a lake-specific satellite-derived dataset

• Published in: Journal of Hydrology: Regional Studies
• Main Authors: Gifty Attiah, Homa Kheyrollah Pour, K. Andrea Scott
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2023
• Subjects: Lake surface temperature; Landsat; Northwest Territories (NWT); Lake Ice; Climate change; Sub-Arctic; Physical geography; GB3-5030; Geology; QE1-996.5; Arctic; Canada; Kendall; North Slave Region; Northwest Territories
• Online Access: https://doi.org/10.1016/j.ejrh.2023.101571; https://doaj.org/article/5d448255d9904a7683eafe4c8ced372e

Study region: This study analyzed lake surface temperature (LST) trends and spatial distribution across 535 predominantly small to medium lakes across the North Slave Region (NSR) of the Northwest Territories (NWT), Canada. Study focus: The NWT is characterized by a vast number of lakes covering a significant portion of its spatial extent. However, there is limited knowledge of how LST responds to climate warming in this region. To address this, LST was analyzed in four distinct periods: open water season (OW), ice cover season (IC), and the transitional months of May (TM) and October (TO). LSTs from 1984 to 2021 were retrieved from a lake-specific satellite-derived LST dataset (North Slave LST). LST trend distribution and relationships were analyzed using the Mann-Kendall test and a multilinear regression model. New hydrological insights: The analysis revealed an overall increase in LST, with average rates (max) of 0.03 °C/year (0.05 °C/year), 0.03 °C/year (0.06 °C/year), and 0.13 °C/year (0.27 °C/year) for OW, TM, and TO, respectively accross study lakes. A faster rate of change was observed in October compared to other periods. Results indicated significant increases in LST for 411 lakes (77%) during OW, 418 lakes (78%) during TO, and 490 lakes (92%) during TM. The spatial distribution and magnitude of LST change were primarily influenced by geographical than morphometric properties. The analysis demonstrated later freeze-up (0.20 day/year) and earlier break-up (−0.17 day/year) of lake ice across the NSR.