Ice margin North Greenland

Ice margin North Greenland

In this project funded by the Greenlandic ‘Pulje C’ we investigate recent changes in the position of the ice margin in North Greenland. In contrast to large parts of the country, we have found examples where it is advancing even though the net mass budget for the ice sheet is significantly negative. We postulate that this has to do with the nature of the ice margin’s near-vertical ice cliffs in this part of Greenland. These cliffs are a result of climatic conditions and ice dynamics and have been only little investigated so far. In the first part of this project, we therefore aim at identifying and analyzing extent, location and characteristics of the land-based ice margin in Northern Greenland. We will use recent high-resolution remote sensing data to classify obvious morphological characteristics such as length, height, aspect and steepness of the cliffs. A recently published dataset of digital elevation models from the 1980s has proven to be of high enough resolution to derive reliable information on ice cliff position. In combination with the recent remote sensing data we can identify spatial advance/retreat patterns and their magnitude. In the last phase of the project, we will re-visit the only well documented ice cliff in North Greenland during summer 2017 (Red Rock ice cliff) where a significant advance is known to have taken place. We will map the current location of the ice cliff and measure the current climatic conditions. A unique 70 year history of ice cliff evolution will be the result. The project is carried out in collaboration with Graz University, Austria, and Utrecht University, The Netherlands.

Surface elevation changes between 1985 and 2015, ice cliff margin 1985 (blue), 2007 (yellow) and 2015 (green). The arrows refer to the approximate flow direction of the ice.