A synthesis of thermokarst lake water balance in high-latitude regions of North America from isotope tracers

• Main Authors: MacDonald, Lauren Ashley, Wolfe, Brent B., Turner, Kevin W., Anderson, Lesleigh, Arp, Christopher D., Birks, S. Jean, Bouchard, Frédéric, Edwards, Thomas W.D., Farquharson, Nicole, Hall, Roland I., McDonald, Ian, Narancic, Biljana, Ouimet, Chantal, Pienitz, Reinhard, Tondu, Jana, White, Hilary
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: NRC Research Press (a division of Canadian Science Publishing) 2016
• Subjects: Arctic; Hudson; Hudson Bay; Nunavik; Old Crow Flats; Yukon; Climate change; Old Crow; permafrost; Thermokarst; Alaska
• Online Access: http://hdl.handle.net/1807/76025; http://www.nrcresearchpress.com/doi/abs/10.1139/AS-2016-0019

Numerous studies utilizing remote sensing imagery and other methods have documented that thermokarst lakes are undergoing varied hydrological transitions in response to recent climate changes, from surface area expansion to drainage and evaporative desiccation. Here, we provide a synthesis of hydrological conditions for 376 lakes of mainly thermokarst origin across high-latitude North America. We assemble surface-water isotope compositions measured during the past decade at five lake-rich landscapes including Arctic Coastal Plain (Alaska), Yukon Flats (Alaska), Old Crow Flats (Yukon), northwestern Hudson Bay Lowlands (Manitoba) and Nunavik (QuĂŠbec). These landscapes represent the broad range of thermokarst environments by spanning gradients in meteorological, permafrost and vegetation conditions. An isotope framework was established based on flux-weighted long-term averages of meteorological conditions for each lake to quantify water-balance metrics. The isotope composition of source water and evaporation-to-inflow ratio for each lake was determined, and results demonstrated a substantial array of regional and sub-regional diversity of lake hydrological conditions. Controls on lake water balance and how these vary among the five landscapes and with differing environmental drivers are assessed. Findings reveal that lakes in the Hudson Bay Lowlands are most vulnerable to evaporative desiccation, whereas those in Nunavik are most resilient. However, we also identify the complexity in predicting hydrological responses of these thermokarst landscapes to future climate change. The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author.