Glaciers are the largest freshwater reservoir on Earth, storing 68% of all freshwater on continents. They are a vulnerable component of the cryosphere, losing mass through calving events and melting (either at the surface or at the glacial bed). Glacial melting comprised of 21% of sea level rise over the last two decades. Large-scale calving events are well-documented and a focus of glaciological research. On the contrary, a relatively small amount is known about processes by which ice melts, is stored, and changes on the surfaces of glaciers. This study aims to categorize the different melt features, such as crevasses, ponds, streams, and blue ice, for Greenland and Antarctic glaciers, and determine their size and abundance. QGIS, an open-source geographic information system application, was used to map and measure the area and length of these features on Helheim Glacier on Greenland and Beardmore, Marsh/Nimrod, and Lennox King Glaciers on Antarctica. The results of this study showed that water-filled crevasses were the largest melt features present on all glaciers, averaging a size of 39.24 km². Most of the other meltwater features were located within or near crevasse fields. The most abundant meltwater features overall were ponds with a total of 75 identified across all 4 glaciers, Marsh/Nimrod Glacier contributing 61 of those ponds. The least abundant as well as the smallest melt features were streams, with an average length of 28.49 km. On Helheim Glacier specifically, blue ice was the most abundant melt feature. This is important to our overall understanding of glacier mass loss and hydrology because it shows that the surfaces of glaciers are dynamic and store meltwater in a variety of features. These features need to be monitored and measured annually to understand their temporal variability and how/if surface meltwater contributes to sea level rise.

Primary Presenter: Jordan McDavid, University of Tampa (jordan.mcdavid@spartans.ut.edu)

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