Petermann Fjord feeds fresh water and glacial ice to Nares Strait. It drains 6% of the Greenland Ice Sheet area and is one of the 4 major outlet glaciers in Greenland. Until very recently, it was the only one still assumed to be stable. A major calving event early this month, which made the news world-wide, has raised speculation that this glacier too may be losing its ice at an accelerated rate. However, 80 to 90% of the melt in this glacier occurs under the ice tongue, where the relatively warm ocean water (slightly above zero degree Celsius) meets the ice and melts the glacier tongue from below. Unfortunately, we cannot see this part of the fjord, we do not know the underwater topography of the fjord in general very well, and measurements of the ocean properties are patchy at best. Currently therefore, we can do little more than speculate over the dynamics of the oceanic circulation which is of such vital importance to the glacial melt at this location. Every piece of information about the water properties, the currents, and the underwater topography will be of great help in understanding how the ocean melts the glacier, as well as if and how this may change in the future. We will therefore take the opportunity while we are in the area to visit Petermann Fjord and measure as much as we can.
As is the case with Nares Strait, measurements are very important but in itself not sufficient to fully understand the dynamics and driving mechanisms of the oceanic circulation in the fjord. The measurements taken during this campaign will therefore be used to test the validity of computer models of the fjord. These models will then be used to investigate the physical processes at work.