| Summary: | Surge glaciers have a unique type of glacial acceleration, surging, in which the glacial system leaves a period of quiescence and experiences velocities that are up to 200 times the non-surge velocities. Surge events play a critical role in sea level rise (SLR), as the mass loss from even a single marine-terminating glacier during a surge has been estimated to be upwards of 0.5 percent of annual global SLR. Glacial hydrology, the water that flows through and below the glacier, plays a critical role in surge evolution and initiation, as the initiation of a surge requires decoupling of the glacier from the bed via reduction of basal friction, which is directly related to the hydropotential and water accumulation at the basal boundary. This work establishes a simple framework for accurately determining the basal pre-surge hydrologic conditions and modeling the subsequent glacial dynamics, which may lead to a surge event. This work takes a combined approach via image classification, algorithmic interpretation of ICESat-2 altimetry data, and 3D glacial modeling. Using satellite imagery, the distribution of surface water is determined via a simple image classification approach. Distribution of glacial surface water is determined via supervised classification of satellite imagery. The volume of surface water is determined by estimating water and ice surface elevation for each water feature with the Density-Dimension Algorithm for ice surfaces. The DDA-ice-2 determines ice surface height, crevasse morphology of wet and dry crevasses and water depth from ICESat-2 ATLAS data. The DDA-bifurcate algorithm determines ice surface height, melt pond morphology, and water depth from ICESat-2 ATLAS data.
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