East Antarctic glacier is stable
On Friday, 14 March 2003, at nine o'clock in the morning, the two Alfred Wegener Institute (AWI) polar aircrafts will arrive back in Bremerhaven Luneort. Scientists measured the ice thickness in the Antarctic glaciers, to work out whether the ice thickness was increasing or decreasing in these areas. From data obtained in the previous season (2001/2002), AWI researchers calculated that the glacier, Jutulstraumen, approximately 120,000 square kilometers in size, belonging to the east Antarctic, had a constant mass. „This glacier is stable“ said Dr. Uwe Nixdorf, scientific leader of the AWI polar aircraft missions, "we are assuming that it is representative for the whole of the east Antarctic". Data from two other glaciers, located at the edge of the west Antarctic, have now also been evaluated. The west Antarctic and the east Antarctic are very different regions, which are separated by the Transantarctic mountains.
The planes and their pilots from the Deutsches Zentrum für Luft- und Raumfahrt (DLR) have been merged into an international cooperative logistical network. In this way, this summer, they substantially contibuted to the success of the European ice drilling project at the Kohnen-Station. In addition, they were able to make comparisons between the “Kohnen” data and the data from the neighbouring station "Dome Fuji“.
Why do sea levels rise?
The project "SEAL" (Sea level CHANGE) should answer the question whether the quantity of the ice in subsections of the Antarctic are increasing or decreasing, and therefore affecting sea levels. In the past season, two glaciers in the west Antarctic were studied: the Slessor glacier and the Bailey Ice Stream. They flow into the Filchner Ice shelf. From the aircraft "Polar 2“, the scientists measured the ice thicknesses of the glaciers. The flow velocities are measured from satellites. Together with the precipitation data, the changes in total ice quantity of the glaciers can be calculated. In the Antarctic summer of 2001/2002 ice thickness of the East Antarctic glacier Jutulstraumen was measured by radar from the airplane. The calculations have now been completed, and resulted in the glacier having a balanced mass equilibrium.
Air lifts in the Antarctic
The network DROMLAN (Dronning Maud Land Air Network) is a co-operation between Russian and Scandinavian polar research institutions and the AWI. For the first time, this year, it was possible to arrive for the European Antarctic expeditions on by air. The approach was made from the Russian station, Novolasarevskaja, by the Twin Otters, carrying scientists further to the British "Halley Station“, and the two AWI stations, "Neumayer“ and "Kohnen“. In this way, the work was able to begin much earlier than in previous years.
50,000 years of climate history
The work on the Kohnen station particularly profited from the use of the polar aircrafts. In the context of the European ice drilling project EPICA (European Project for Ice Coring in Antarctica) the scientists drilled for ice which containes information about the climatic history of the Antarctic. In this season, a depth of 1551.55 meters was reached. The ice from this depth is about 50,000 years old. The new depths, of over one thousand meters achieved in this year, were only made possible, due to improved flight logistics, allowing the scientists to work for four weeks longer than previous years.
Old Ice dates
From the aircraft, scientists were able to study the ice forces/straength and structures between Kohnen station and the Japanese station "Dome Fuji“ The Japanese station lies about one thousand km from Kohnen station at a height of 3900 meters. Previously, ice cores have been drilled there down to more than 2700 meters and then dated. With the special ice radar system on the "Polar 2" the ice layers from Dome Fuji to Kohnen could be studied. Scientists are then better able to interpret the data from both cores. The ice core from the Kohnen station will take the climatic researchers about 300,000 years into history.
Bremerhaven, 12.3.2003
Polar aircrafts back from Antarctic
