The impacts of rapidly receding glaciers on proglacial freshwater resources and ecological services

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Human-induced climate change is the most pressing environmental issue of our time, threatening the security of our water and food supply, ecosystem and human health, and socioeconomic wellness. Indeed, access to clean freshwater, and the natural goods and services it provides, is a fundamental human right. Glaciers provide essential freshwater to more than a sixth of the world's population, yet climate warming is resulting in a decline of global glacier volume, with coincident changes to downstream runoff. Lowering greenhouse gas emissions to preserve our remaining glaciers and river flows is vital for ensuring some level of global water security. However, it is equally essential to quantify the changes in glaciological, biogeochemical, and limnological processes that are already occurring in the rapidly evolving proglacial landscapes forming in front of retreating glaciers. Assessing these changes will allow us to understand how glacial retreat will influence freshwater quality and ecosystem function further downstream, where most of the human population lives and works. For example, loss of glacial mass may result in the large releases of nutrients, ancient organic carbon and contaminants historically archived in glacial ice and buried beneath glaciers, all of which could impact downstream freshwater quality, productivity, resources and ecological services. In contrast, as glacial rivers cross newly-emerged proglacial landscapes, they may actually consume atmospheric carbon dioxide (CO2) via chemical weathering of some of the abundantly available freshly comminuted fine-grained minerals they entrain. As such, there are four objectives to my proposed research program, each aligning with a graduate student project, and additional training of undergraduate students, Inuit and other northern peoples, and laboratory technicians: (1) characterize the geochemical processes that consume CO2 in proglacial rivers and lakes; (2) determine the global extent of this CO2 consumption; (3) quantify biological productivity in proglacial lakes; and (4) quantify seasonal, interannual and spatial patterns in global proglacial freshwater chemistry. This innovative, interdisciplinary, and collaborative research and training program will have two major scientific impacts: it will (1) enhance our understanding of regional and global CO2 budgets (Objectives 1 and (2) improve our knowledge of regional and global proglacial freshwater quality and services (Objectives 3a resource that is vital for basic food and drinking water security. Indeed, the traditional lifestyles of many human populations around the globe rely on the crucial and highly vulnerable freshwater resources that originate from glaciers. Therefore, increasing our knowledge of these resources, and how they may change in the future, is critical.