Detailed project information

This coordinated research proposal defines the Netherlands contribution to IPY research into the dynamics and mass balance of Arctic glaciers. If they were to melt completely, Arctic glaciers, including the Greenland ice sheet, have the combined potential to increase global sea level by 8 m. Arctic glaciers have lost a considerable amount of mass in the last century (see the Arctic Climate Impact Assessment report, ACIA), thereby contributing significantly to the observed sea level rise of 2 mm per year. Recent research shows that Arctic glaciers may be capable of reacting much faster to changes in climate and surface mass balance than previously assumed. Observations show that an increased flux of surface melt water that has drained to the glacier bed during recent warmer summers leads to increased glacier velocities. The thinned glacier surface is situated in a warmer environment, thereby experiencing increased melting and so forth. Understanding and being able to model this phenomenon is very important because this positive feedback could lead to a collapse of, for instance, the Greenland ice sheet that is much faster than has been assumed so far. To achieve this, intensive observations of ice velocity and meltwater production will be carried on five Arctic glaciers, including an outlet glacier on the Greenland ice sheet (subproject 1). Another important question we want to answer is how the Greenland ice sheet evolved through the last interglacial (Eem, subproject 2); the Eem was several degrees warmer than today?s climate, and could serve as an analogue of a future enhanced greenhouse climate. To calculate the surface mass balance of the Greenland ice sheet, a prerequisite for accurate ice volume calculations, we will use a regional atmospheric climate model (subproject 4). The Netherlands will also participate in the new deep drilling in north Greenland to reconstruct climate of the north Atlantic region over the last 140,000 years. By analysing the concentration and isotopic composition of methane in air trapped in the ice, we hope to be able to determine and locate the main methane sources on Earth (subproject 3).

Articles

• (2007). Het grote ijs (the big ice). Sonnenwijzer. pp. 3-5