Mélange variability around Greenland yields insights into calving dynamics and conditions that favor mélange formation

Abstract:

The presence of proglacial mélange adjacent to marine terminating outlet glaciers is thought to play a significant role on calving behavior and glacier stability by exerting a buttressing effect on the calving face. However, most studies focus on single glacier systems and the variability of characteristics (rigidity, extent) within permanent mélange. Many glaciers around Greenland have a short-lived mélange that persists for a week or several weeks. We create time series of mélange occurrence around the Greenland Ice Sheet from 2017 – present, using Google Earth Engine. We compare these results with our coincident databases of terminus position and iceberg distributions, and publicly-available data of glacier velocity. By exploring the behavior of glaciers with and without a pro-glacial mélange, we assess whether mélange occurrence impacts calving dynamics. In addition, we quantify metrics (glacier and fjord geometry, fjord conditions, calving style) that favor short-lived mélange formation.