Collaborative Research: Arctic Hydrological Regime Shift in a Warming Climate

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The Arctic is currently warming faster than any other region of the globe, and recent changes in climate and hydrology have had direct impacts in Svalbard, where flash flooding and enhanced mass movement over frozen ground on steep slopes has occasionally led to catastrophic slope failure. This study will examine how warming is leading to a new hydrological regime in regions adjacent to the areas where major sea-ice losses have occurred. The new hydrological regime is result of an increase in annual precipitation, a higher proportion of which is in the form of rain rather than snow, especially in the transition seasons of fall and spring. Under this collaborative project, the team will study annually laminated sediments in lakes of western Svalbard (Norwegian Arctic) to identify the sedimentary signal of recent changes in hydrology and use this to reconstruct the long-term history of rainfall-related sedimentary events to determine when similar conditions may have prevailed in the past. This project will involve a postdoctoral scientist, a graduate student, and undergraduate students at University of Massachusetts and Bates College, as well as teacher in the research. There is training of STEM teachers through a summer program enabling them to incorporate Arctic earth science activities into their classroom curricula. This project will examine how warming is leading to a new hydrological regime in regions adjacent to the areas where major sea-ice losses have occurred. The investigators will study annually laminated sediments in lakes of western Svalbard to identify the sedimentary signal of recent changes in hydrology and reconstruct the long-term history of rainfall-related sedimentary events to determine when similar conditions may have prevailed in the past. The type and amount of sediment transported to lakes carries with it information about meteorological and hydrological conditions in the lake watershed. The investigators will recover sediment cores to study the structure and grain size profiles of recent years of sediment accumulation, to compare with meteorological measurements, sediment recovered in traps, and measurements of processes responsible for sediment transport and deposition. They will employ microanalytcal techniques for high-resolution grain size analysis, varve detection and measurement. Using scanning electron microscope image analysis methods, they will reconstruct rainfall-driven sedimentary events. Sediments acquired from sediment traps will be analyzed using a laser particle size analyzer to obtain sub-annual scale grain size profiles to compare with observed hydroclimatic events and the varved records. This will provide a unique perspective on the nature of recent sedimentary changes and provide insight into the effects of contemporary changes in climate on the hydrological regime of this region. The results will have implications for other parts of the Arctic where sea-ice is rapidly receding.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.