Modelling glacier and ice sheet response to climate change

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This research program aims to improve understanding of glacier and ice sheet response to climate change. My research group uses a combination of glaciological modelling and glacier-climate field studies to assess changes in glacier mass balance and to examine the role of glaciers as a dynamic component of Earth's climate system. Regionally, glacier and icefield retreat affects alpine ecology, tourism, hydroelectric power generation, and the supply of surface water for significant population bases and agricultural activities. We are developing glaciological models to simulate glacier and ice sheet evolution over decadal time scales. Field studies for the period 2009-2014 will focus on historical and future icefield changes and water resource implications in western Canada, building on our established research program on the Haig Glacier, Canadian Rockies. Beginning in spring 2009, we will expand these efforts to the Illecillewaet Glacier, Glacier National Park, B.C. The Illecillewaet is a headwaters region of the Columbia River, with a high percentage of glacier cover and a more maritime-influenced climate. Meteorological controls of snow accumulation and snow/ice melt may differ significantly from those in the Canadian Rockies. Globally, glacier and ice sheet retreat has accelerated the rate of sea level rise, with considerable uncertainty as to how much additional sea-level rise can be expected this century. Advances in coupled glacier-climate modelling are needed to address this. This includes a number of numerical modelling issues that we aim to confront: the inclusion of higher-order terms in the ice sheet stress balance, improvements to the numerical representation of glacier and ice sheet margins, and downscaling strategies for regional climate patterns in areas of complex topography. Climate fields need to be extrapolated from sparse observational records or interpolated from climate models (or reanalyses) to the scale of influence for glacier and ice sheet mass balance, order 1-10 km. Our field studies support the numerical modelling through examination of mass balance processes and high-elevation temperature and precipitation gradients, providing constraints on free parameters in regional- and global-scale glaciological modelling.