The Greenland Ice Sheet, Glaciers and Ice Core Drilling
The Greenland Ice Sheet is melting which is leading to increased glacier activity, more ice caps and an augmented flow of fresh water to the oceans around Greenland. The rate of melting has accelerated significantly throughout the last decade compared with the preceding decade. While an annual mass reduction of 50 gigatonnes was recorded in the period 1995-2000, this rose to 200 gigatonnes per year in the period 2004-2008. The present annual mass loss is enough to supply a billion city dwellers with water. The decline is expected to continue accelerating over the coming years and it is suggested that a 10-30% loss in the mass of glaciers and ice caps might be observed by the end of the century1.
Research on the Greenland Ice Sheet is based on monitoring and ice core drilling. While monitoring programmes follow climatic conditions in the present, ice core drilling helps to improve the understanding of climatic variations in the past.
The Centre for Ice and Climate at the Niels Bohr Institute at Copenhagen University carries out ice core drilling in the Greenland Ice Sheet. Analyses of the ice cores give insight into prehistoric climate patterns and in that way create a basis for future projections of our climate.
Research institutions in Greenland manage a number of different monitoring stations. Some measure the thickness of the ice, while others follow how the ground below the ice sheet rises as a consequence of the accelerating mass loss.
PROMICE – Programme for Monitoring the Greenland Ice Sheet – is a project run by the Geological Survey of Denmark and Greenland (GEUS), the Technical University of Denmark (DTU) and Asiaq, Greenland’s Survey. The project follows the continuous mass loss of the Greenland Ice Sheet. Monitoring is concerned with melting as well as with the increasing productions of ice caps in the fjords. It is carried out by weather stations spread across the ice sheet as well as with the use of GPS and satellite.
Zackenberg is a research station in Northeastern Greenland that monitors changes in climate, weather conditions, ecosystems, glaciology and hydrology. The station is run by Århus University. Data is collected at Zackenberg as well as on smaller stations in the surrounding area. The monitoring programme GlacioBasis is of special interest for improving the understanding of the ice sheet. The programme generates data on energy balances at the surface of the ice sheet and follows glacier activity by the Zackenberg River drainage basin.
Summit Station supports a wide range of climate-related research through data collection and ice core drilling. The station is located at an altitude of 3200 meters, 400 kilometres from the coast and is run by the National Science Foundation based in the United States.
The satellite Crysat-2 measures the thickness of the ice sheet on a frequent basis and forms part of the European Energy Agency’s mission to monitor changes in the Earth’s ice-covered areas, both on land and at sea. The work is supported by the National Space Institute at the Technological University of Denmark (DTU Space) that also runs their own projects through which they monitor changes in the thickness of the ice sheet.
1 AMAP, 2011. Snow, Water, Ice and Permafrost in the Arctic (SWIPA): Climate Change and the Cryosphere. Arctic Monitoring and Assessment Programme (AMAP), Oslo.