Characteristics of a surge of Franklinbreen detailed from remote sensing archives

In recent years, a number of glaciers in the Arctic have rapidly surged or destabilized. These events have been characterized by the rapid transfer of land-based ice to the ocean, with speeds in excess of 20 m/d, surface lowering often in excess of 20 m/yr, and front advances of several kilometers. Here, we examine the development of a speed-up and possible surge of Franklinbreen, an outlet glacier of the ice cap Vestfonna in NE Svalbard. Using re-processed Landsat imagery, digital elevation models and surface velocity maps derived from a variety of sources, we map the glacier's front position, surface velocity, and surface elevation between 1976-2019. Preliminary results show that over this period, the northern terminus of the glacier advanced nearly 2 km, with nearly 50 m surface elevation increase. The southern terminus of the glacier remained nearly stationary, with thickening of over 50 m near the terminus, and an increase in surface velocity from near stagnation to over 1 m/d at the terminus in 2019. While a number of the
characteristics of this surge development are remarkably similar to other recent surge events, the glacier has not reached the speeds observed in other recent surge events. With further detailed examination of the available satellite record, we hope to provide a more thorough picture of the development of the speed-up and surge, and use these
contrasting characteristics to gain further insight into glacier instabilities.