Dynamic Activation of a Marine-terminating Arctic Ice Cap

Tuesday, 16 December 2014
Malcolm McMillan1, Andrew Shepherd1, Noel Gourmelen2, Amaury Dehecq3, Amber Alexandra Leeson4, Andrew Ridout5, Thomas Flament6, Anna Elizabeth Hogg7, Lin Gilbert5, Toby J Benham8, Michiel R van den Broeke9, Julian A. Dowdeswell10, Xavier Fettweis11 and Tazio Strozzi12, (1)University of Leeds, Leeds, LS2, United Kingdom, (2)University of Edinburgh, Edinburgh, United Kingdom, (3)LISTIC / Université de Savoie, Annecy-Le-Vieux, France, (4)University of Durham, Durham, United Kingdom, (5)University College London, London, United Kingdom, (6)University of Leeds, School of Earth and Environment, Leeds, United Kingdom, (7)University of Leeds, Leeds, United Kingdom, (8)Scott Polar Research Institute, Cambridge, United Kingdom, (9)Utrecht University, Utrecht, Netherlands, (10)Scott Polar Research Institute, University of Cambridge, Cambridge, United Kingdom, (11)University of Liège, Geography, Liège, Belgium, (12)Gamma Remote Sensing, Guemligen, Switzerland
The melting of valley glaciers and ice caps is responsible for approximately one third of recent global sea level rise. Mass losses have increased in recent decades and are expected to remain significant for at least another century. However, large uncertainties relating to the dynamic contribution of marine-terminating glaciers and ice caps remain, in part due to a lack of observations. Satellite sensors provide an important tool for monitoring these remote glacial systems, although the relatively restricted size of these smaller bodies of ice has, in the past, made such observation challenging, limiting the number of geodetic techniques available and the period over which such measurements have been made. Several recent missions, however, offer improved resolution and the capability for detailed observation of these areas. Here we use data acquired by a range of satellite sensors, including CryoSat-2, ICESat, Sentinel-1a, TerraSAR-X and ALOS, to study the decadal evolution of Austfonna, the largest ice cap in the Eurasian Arctic. We will focus on one marine-terminating sector which has been rapidly losing ice to the ocean, investigating the dynamic activation of this formerly slow-flowing area and the resulting development of widespread dynamical imbalance within this region.