CGRG Bibliography of Canadian Geomorphology
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Author : Bennett, K.; Werner, A.; and Schnorbus, M.
Date : 2010.
Title : Uncertainties in hydrologic and climate change impact analyses in headwater basins of British Columbia.
Publication : CMOS-CGU Ottawa 2010. 44th Annual CMOS Congress, 36th Annual Scientific Meeting of CGU, 3rd Joint CMOS-CGU Congress. May 31-June 4, 2010. Ottawa, Ontario.
Issue :
Page(s) :
Abstract
Preparation for water resource adaptation to climate change requires an accurate measure of the uncertainty associated with future projections of change to streamflow and water balance. This study examined hydrologic impacts in four BC watersheds (Fraser, Peace, Columbia and Campbell) for a range of downscaled Global Climate Model (GCM) emission scenarios to illustrate the uncertainty in hydrologic response to climate change. Uncertainties in water balance (runoff, evapo-transpiration, snow water equivalent (SWE), soil moisture) were analysed by forcing the Variable Infiltration Capacity (VIC) hydrologic model, run for 25 optimal parameter solution sets, with 10 Bias-Corrected Statistically Downscaled (BCSD) GCM emission scenario projections for the 2050s and the 2080s. The range in the 10 GCM-emission scenarios compared to the hydrological uncertainty of the 25 pareto solution parameterizations are greater between GCM-emission scenarios than the differences within the GCM-emission scenarios. Results show varying responses depending on geography and eco-climatic gradient of the basins. In general, there is little difference between scenarios in the 2050 results, but by the 2080s, the scenario differences begin to emerge. The 2050 projections show increases in winter runoff, decreases in summer runoff, variable responses in evapo-transpiration (increases or decreases) and decreases in April 1st SWE across BC. The greatest amount of projected change occurs during the winter period. For most water balance results, the 2080 projections are doubled from the 2050s results. Some scenarios project increased SWE in the Kicking Horse watershed (Columbia River basin) to the 2050s, while slight declines are projected for the 2080s. The responses to climate change are likely dependant on the hydrologic regime and physiography of an individual basin; therefore water managers who require an understanding of how climate change and uncertainty in climate change projections will impact their watersheds should consider conducting analysis on a range of GCM-emission scenarios, downscaled to their region of interest.
Bibliography of Canadian Geomorphology