Modelling glacial overdeepenings and future lake locations for the western Canadian Cordillera

Mountain glaciers are melting at an increased rate due to climate change; this is leading to decreasing water resources for the surrounding communities, which is becoming of increasing importance in western Canada as glacier volume is expected to reduce by 70% by 2100. As a glacier melts, a lake can be formed in front of the glacier. This lake is formed due to a depression (herein called 'overdeepenings') in the landscape which has been scraped out by glacial erosion, this then fills with the generated melt water once the glacier retreats out of it and can then become dammed by deposited moraines. As these lakes continue to develop and grow, while the glacier continues to shrink, they have the potential to become hazardous, if a sudden release of water occurs, while they can become opportunities for economic benefits - such as hydroelectric dams and tourism - when the glacier disappears.

Research on the formation and development of these glacial lakes has been discussed at length within the literature and is well understood. The vast majority of the research at present has focused on these glacial lakes as hazards, focusing on negative impacts such as; decreasing water resources, and the effects on downstream communities. A question which has received very little attention in the literature - and that shall be answered by this study - is that of where these glacial lakes will develop in the future as global warming causes glaciers to disappear and what these locations will look like as these, now relic, lakes dominate the environment?

A limited number of studies have been trying to answer this question in to where these glacial lakes will be in the future, with a primary focus on locations of relatively important consequence, for example the Himalaya-Karakoram region. Another study, taking a more global perspective, looked into the possibility of these lakes for hydroelectric dams, which would be important contributions to national energy supplies in many countries. Both studies used estimated glacial ice thicknesses to predict where these overdeepenings have been located. Although these studies provide an understanding on the formation of future lakes, and how they will evolve, no study has tried to describe or understand what these locations will look like once these glaciers disappear and the lakes are all that remain.

This study shall be working in British Columbia and Alberta in western Canada, where we shall predict where these glacial overdeepenings are under the present-day glacial ice. This shall be done by using already created estimations on global glacial ice thicknesses, and digital elevation models. These shall be used to estimate the depth and volume of lakes which maybe created in the future. We shall then compare what these future landscapes shall look like using modern day locations which are either transitioning from a glaciated to deglaciated environment with glacial lakes dominating the landscape (Cordillera Blanca, Peru), and locations that are entirely deglaciated and that the once glacial lakes, now remain (e.g. The Lake District, UK). In these localities, mapping of the moraine dams will aid in providing an understanding of where future lakes may develop. The output of this research will aid in giving an understanding on the location of future lakes within western Canada, which will assist in future decision making of the local government into water availability in an unpredictable climate.