Potential Hydrologic Impact of Climate Change to Athabasca River Basin based on Dynamically Downscaled Climate Scenarios of IPCC

Abstract

To investigate the potential hydrologic impact of climate change on the Athabasca River Basin (ARB) of Alberta, Canada, the fully distributed physically based model, Modified Interactions Soil-Biosphere-Atmosphere (MISBA) land surface scheme of Kerkhoven and Gan (2006) was driven with two SRES climate change scenarios (A1B and A2) of four General Circulation Models (GCMs) of IPCC (2007) dynamically downscaled by MM5, to simulate the future water availability of ARB for 2050s and 2080s. MM5 is the Fifth-generation Mesoscale Model jointly developed by the Pennsylvania State University (PSU) and the National Center for Atmospheric Research (NCAR). The four GCMs selected were ECHAM5 (wettest), MIROC3.2 (warmest and driest), CGCM3 and CCSM3 (moderate). Due to warming, the future streamflow of ARB simulated by MISBA show that ARB is generally expected to experience a decrease in streamflow. The management of ARB’s water resources system should be adjusted to augment against possible shortfall to various users relying on ARB for water supply. The results of this study based on climate scenarios of GCMs dynamically downscaled by MM5 are compared with results of Kerkhoven and Gan (2011) for ARB based on climate scenarios that were statistically downscaled.