Unique Data from the Arctics Winter Atmosphere Brought Home
15.04.2008 - Logistics, Other
German scientist Jürgen Graeser, a member of the Potsdam Research Unit of the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association, returned to Germany in April 2008 after having spent seven months on a drifting ice floe. Over the course of the International Polar Year, this was the first time that a foreigner was allowed to take part in the German drift expedition NP35 (35 North Pole Drift Expedition), an expedition carried out from September 2007 to September 2008.
Jürgen Graeser regularly sent out a tethered balloon filled with helium in a region which is normally inaccessible during the Arctic winter. He measured the meteorological structure of the Arctic boundary layer, where heat, moisture and impulse exchange processes take place between the earth's surface and atmosphere (up to 400 metres in altitude). Six sensors registered temperature, moisture, air pressure and wind data which were then sent to Greaser's computer and, later in Potsdam, interpreted using regional climate model simulations.
Graeser also sent a research balloon tagged with a radiosonde and an ozone sensor up to 30 km in altitude in order to collect vertical high-resolution ozone data, a rarety over the central Arctic. After recent colder than usual winters have occurred at this altitude, fostering significant destruction of the ozone layer, it is important to determine exactly how much of this destruction is caused by human activity.
The data brought home to Germany by Graeser will contribute to reduce the imprecision of present climate models in polar regions. The Russians, who are recording atmospherial data and measuring the ocean's top layer, characteristics of the sea ice, snow coverage and energy balance above the ice surface, will continue to do so until their planned evacuation from the station in September 2008.
