From global change to regional response: Integrating global and regional climate model simulations with alpine glacier mass balance and downstream hydrology

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The impact of future climate change on glaciated regions of the world (both high altitude and high latitude) has important ramifications for the availability of freshwater. Sectors highly dependent on sustained and robust levels of glacial/snow meltwater during the summer melt season include agriculture, hydroelectric power production, and public availability of freshwater. Other related factors dependent on Earth's glaciers include global sea level, the geopolitics of trans-border river flows, and the dangers of Glacial Lake Outburst Floods (GLOFs). In certain regions of the world (for example, the countries spanned by the Himalaya) glacial meltwater is the primary source of freshwater yet GLOFs have been on the increase in the Himalaya, the Alps, and the Andes, killing thousands of people and causing millions of dollars in damage to settlements, infrastructure, and livestock. I plan to focus the research outlined below on two sensitive regions of the globe: western Canada (British Columbia and Alberta) and the Himalaya (Pakistan, India, and Nepal).******The physical links and interactions between global climate, regional climate, alpine glaciers, and hydrology have not been explored. There are numerical models for each of these facets of the climate system but linking them together in a robust way that is capable of forecasting is a significant numerical challenge given the disparate spatial and temporal scales on which each component operates.******My group at the University of Alberta has focused on climate change over the western Canadian Cordillera and the Himalaya under a “business-as-usual” emission scenario for the next century, and we have incorporated global and regional climate models to address these issues. We are now focused on a high-end emission scenario using the latest coupled atmosphere-ocean GCM (ESM2M) from the Geophysical Fluid Dynamics Laboratory in Princeton. The Weather Research and Forecasting model (WRF) has been our tool for downscaling the GCM data. We have developed a glacier mass balance model within WRF that is interactive with the atmospheric model and can also represent debris-covered glaciers, which are so prevalent in the Himalaya. The next step in this chain of numerical work is to link predictions of glacier mass balance with hydrology and downhill streamflow, with particular attention paid to detailed topography, the possibility of glacial lake formation, and freshwater availability. A number of distributed hydrological models are available that can exploit results from WRF simulations for future climates. We have started by using the SWAT hydrology model and have configured it for use over both Alberta and Nepal.******The proposed research integrates the fields of atmospheric, oceanic, cryospheric, and hydrologic modelling while retaining an element of fieldwork groundtruthing for the model development.********