Multiyear variations in High Arctic river temperatures in response to climate variability

Arctic Science

article

Christopher Bolduc¹  Scott F. Lamoureux¹ 

[1] Department of Geography and Planning, Queen’s University

关键词: water temperature;    Arctic;    snow;    permafrost;    climate change.;   

DOI  :  10.1139/as-2017-0053

学科分类：地球科学(综合)

来源: NRC Research Press

【 摘 要 】

Water temperature measurements (2004–2016) from two small rivers in the High Arctic were analyzed to determine the effects of climate variability on thermal regime and the sensitivity to climate change. The East and West rivers (unofficial names) drain similar watersheds (11.6 and 8.0 km 2 , respectively) and are located at the Cape Bounty Arctic Watershed Observatory (CBAWO), Melville Island, Canada (74°55′N, 109°35′W). Differences in seasonal timing of river temperatures were evident when comparing the coldest and warmest years of the study period, and across different discharge conditions. Snowmelt runoff is characterized by uniformly cold water (∼0–1 °C) over a wide range of discharge conditions, followed by warming water temperatures during flow recession. The rivers showed varying sensitivity to mid-summer air temperature conditions in a given year, with warmer years indicating high correlation ( r 2  = 0.794–0.929), whereas colder years showed reduced correlation ( r 2  = 0.368–0.778). River temperatures reached levels which are reported to negatively affect fish and other cold-water aquatic species (>18 °C) with greater frequency and duration during the warmest years. These results provide a basis to further enhance prediction of river thermal conditions to assess ecosystem health in a river system and to refine insights into the effects of climate change on High Arctic aquatic ecosystems.

【 授权许可】

CC BY