Hydrol. Earth Syst. Sci., 25, 2513–2541, 2021 https://doi.org/10.5194/hess-25-2513-2021 © Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. The spatial extent of hydrological and landscape changes across the mountains and prairies of Canada in the Mackenzie and Nelson River basins based on data from a warm-season time window Paul H. Whitfield1,2,3, Philip D. A. Kraaijenbrink4, Kevin R. Shook1, and John W. Pomeroy1 1Centre for Hydrology, University of Saskatchewan, Saskatoon, SK, S7N 1K2, Canada 2Department of Earth Sciences, Simon Fraser University, Burnaby, BC, Canada 3Environment and Climate Change Canada, Vancouver, BC, Canada 4Geosciences, Utrecht University, Utrecht, the Netherlands Correspondence: Paul H. Whitfield (paul.h.whitfi
[email protected]) Received: 24 November 2020 – Discussion started: 4 January 2021 Revised: 30 March 2021 – Accepted: 8 April 2021 – Published: 18 May 2021 Abstract. East of the Continental Divide in the cold inte- separating the Canadian Rockies and other mountain ranges rior of Western Canada, the Mackenzie and Nelson River in the west from the poorly defined drainage basins in the basins have some of the world’s most extreme and variable east and north. Three specific areas of change were iden- climates, and the warming climate is changing the landscape, tified: (i) in the mountains and cold taiga-covered subarc- vegetation, cryosphere, and hydrology. Available data consist tic, streamflow and greenness were increasing while wetness of streamflow records from a large number (395) of natu- and snowcover were decreasing, (ii) in the forested Boreal ral (unmanaged) gauged basins, where flow may be peren- Plains, particularly in the mountainous west, streamflows nial or temporary, collected either year-round or during only and greenness were decreasing but wetness and snowcover the warm season, for a different series of years between were not changing, and (iii) in the semi-arid to sub-humid 1910 and 2012.