Spatial and Temporal Variability of Glacier Surface Velocities and Outlet Areas on James Ross Island, Northern Antarctic Peninsula

Abstract

The northern Antarctic Peninsula was affected by a significant warming over the secondhalf of the 20th century and the collapse of several ice shelves. Local climate conditions on James RossIsland on the northeastern coast can differ strongly from the main part of the Antarctic Peninsula.This paper reports the spatial and temporal variability of glacier surface velocities and the area oftheir outlets throughout James Ross Island, and evaluates potential relationships with atmosphericand oceanic conditions. Velocity estimates were retrieved from intensity feature tracking of scenesfrom satellite synthetic aperture radar sensors TerraSAR-X and TanDEM-X between 2014 and 2018,which were validated against ground observations. Calving front positions back to 1945 were usedto calculate outlet area changes for the glaciers by using a common-box approach. The annualrecession rates of almost all investigated glacier calving fronts decelerated for the time periods2009–2014 and 2014–2018 in comparison to the period 1988–2009, but their velocity patterns differed.Analysis of atmospheric conditions failed to explain the different patterns in velocity and areachanges. We suggest a strong influence from local bathymetric conditions. Future investigations ofthe oceanic conditions would be necessary for a profound understanding of the super-position ofdifferent influencing factors.