Featured Research

from universities, journals, and other organizations

Seven Months On A Drifting Ice Floe

Date:
April 18, 2008
Source:
Helmholtz Association of German Research Centres
Summary:
For the first time, a German has taken part in a Russian drift expedition. He has spent seven months on an ice floe and gained observational data from a region, which is normally inaccessible during the Arctic winter.

Juergen Graeser with research balloon and his red tethered balloon, called "Miss Piggy".
Credit: Image courtesy of Helmholtz Association of German Research Centres

For the first time, a German has taken part in a Russian drift expedition and has explored the atmosphere above the central Arctic during the polar night. Jürgen Graeser, a member of the Potsdam Research Unit of the Alfred-Wegener-Institute for Polar and Marine Research in the Helmholtz Association, has just returned home to Germany. As a member of the Russian expedition NP 35 (35. North Pole Drift Expedition), which consisted of 21 persons, he has spent seven months on a drifting ice floe in the Arctic.

The 49-year-old scientific technician has gained observational data from a region, which is normally inaccessible during the Arctic winter and therefore widely unexplored. Ascends with a tethered balloon up to an altitude of 400 metres as well as balloon borne sensor ascends up to an altitude of 30 kilometres provided data which will contribute to ameliorate existing climate models for the Arctic.

In spite of its importance for the global climate system, the Arctic is still a blank on the data map. Up to now, continuous measuring in the atmosphere above the Arctic Ocean is missing. „We are not able to develop any reliable climate scenarios without disposing of data series with high temporal and local resolutions about the Arctic winter. The data which Jürgen Graeser has obtained in the course of the NP 35 expedition are unique, and they are apt to considerably diminish the still existing uncertainties in our climate models“ said Prof. Dr. Klaus Dethloff, project leader at the Alfred Wegener Institute for Polar and Marine Research.

Russian-German co-operation

Since 1937/38, the Russian Institute for Arctic and Antarctic Research (AARI) has already operated 34 Russian North Pole drift stations. In the course of the International Polar Year 2007/2008, for the first time a foreigner was allowed to take part in a drift expedition (NP 35). Due to their close co-operation with the AARI, the scientists of the Potsdam Research Unit of the Alfred Wegener Institute now could realize a project to research the polar atmosphere in the hardly accessible region of the Arctic Ocean.

The expedition NP 35

From September 2007 to April 2008, the scientific technician Jürgen Graeser from the Potsdam Research Unit was a member of the NP 35 team. For seven months, the 49-year-old has lived and worked together with twenty Russian colleagues on an ice flow the size of three times five kilometres. While Graeser concentrated on measuring the Arctic atmosphere, the Russian scientists performed investigations of the ocean top layer, the characteristics of the sea ice, the snow coverage and the energy balance above the ice surface. Moreover, they recorded atmospherical data concerning temperature, moisture, wind and air pressure by means of earth stations as well as with ascends of radio sensors. In the course of the winter the ice floe drifted 850 kilometres in northwestern direction over the Arctic Ocean.

In April Jürgen Graser was picked up from the ice floe by Polar 5, the research aircraft of the Alfred-Wegener-Institute. A specialised pilot, Brian Burchartz from Enterprise Airlines Oshawa, Canada, accomplished the difficult landing and take-off operation on the ice. “I experienced my stay on the ice floe as an incredible enrichment, under personal as well as professional aspects,” Jürgen Graeser said. The Russian colleagues will continue their measurements until the planned evacuation of the station in September 2008.

The exploration of the atmospheric boundary layer

During the drift Jürgen Graeser has explored the atmosphere above the Arctic Ocean. In order to measure the meteorological structure of the Arctic boundary layer and its temporal changes, he regularly sent out a tethered balloon filled with helium. The six sensors fixed on the tether registered data for temperature, air pressure, moisture and wind and sent them to Greaser’s computer. The exchange processes of heat, impulses and moisture between the earth surface and the atmosphere, which are important for the climate, take place in the layer between the ground and an altitude of about 400 metres.

For the first time now the local and temporal structure of ground-level temperature inversions was measured during the complete polar night. To evaluate and interpret the data, the scientists in Potsdam performed simulations with a regional climate model of the Arctic. Preliminary comparisons of temperature profiles measured on the ice floe with those from the regional climate model underline the importance of the measurements performed by Jürgen Graeser. Considerable deviations are shown between the observed data and model data in the region between the ground and an altitude of about 400 metres. Subsequent research activities in Potsdam focus on the connection of the Arctic boundary layer with the development and the tracks of low-pressure areas.

The investigation of the atmosphere – ozone

Vertical high-resolution ozone data from the central Arctic are rare. To close this data gap, Jürgen Graeser regularly launched a research balloon equipped with a radiosonde and an ozone sensor. These balloons carry the sensors up to an altitude of about 30 kilometres. In the past winter, the region of the ozone layer in an altitude of about 20 kilometres was exceptionally cold, thus continuing the trend to colder conditions in this altitude that was observed in the past. The cold conditions have fostered considerable destruction of the Arctic ozone layer in the past winter. The unique measurements of NP 35 will significantly contribute to determine precisely how much of the ozone destruction is caused by human activities.

„The high amount of work caused by the extensive measuring program let the time on the ice flow go by extremely fast“, Jürgen Graeser said on his return. Daily life was structured by the measurements on the one hand and by the meals with the colleagues on the other. A cook was responsible for the meals of the whole team, but each overwinterer helped him with the kitchen work for one day every three weeks. This kitchen service coincided with the station service controlling the condition of the ice floe and the presence of polar bears near the station. These tasks turned out to be very important, for in the course of the winter the ice floe produced crevices several times, but those crevices closed again. Moreover, frequent visits of polar bears regularly caused for alarm among the participants. Jürgen Graeser had the possibility to communicate with the Potsdam colleagues via satellite telephone and to relay the actual measuring data promptly.

Future projects

The long-term aim is to significantly reduce the great imprecision of present climate models in polar regions. To create models, mathematical descriptions for physical processes taking place under natural conditions are used. These so-called „parameterizations“ are based on measured data, and only an excellent data base can enable them to produce realistic climate simulations. In November 2008, the scientists taking part in the NP-35 project will discuss the results of their expedition in the course of an international workshop in Potsdam. Altogether, the NP-35 project is one more significant milestone for the Potsdam atmospheric researchers. The results deliver an important base for the international focal projects CliC (Climate and Cryosphere) and SPARC (Stratospheric Processes and their Role in Climate Change) by the World Climate Research Programme (WCRP, wcrp.wmo.int/)

.


Story Source:

The above story is based on materials provided by Helmholtz Association of German Research Centres. Note: Materials may be edited for content and length.


Cite This Page:

Helmholtz Association of German Research Centres. "Seven Months On A Drifting Ice Floe." ScienceDaily. ScienceDaily, 18 April 2008. <www.sciencedaily.com/releases/2008/04/080414103617.htm>.
Helmholtz Association of German Research Centres. (2008, April 18). Seven Months On A Drifting Ice Floe. ScienceDaily. Retrieved August 20, 2014 from www.sciencedaily.com/releases/2008/04/080414103617.htm
Helmholtz Association of German Research Centres. "Seven Months On A Drifting Ice Floe." ScienceDaily. www.sciencedaily.com/releases/2008/04/080414103617.htm (accessed August 20, 2014).

Share This




More Earth & Climate News

Wednesday, August 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Unsustainable Elephant Poaching Killed 100K In 3 Years

Unsustainable Elephant Poaching Killed 100K In 3 Years

Newsy (Aug. 20, 2014) — Poachers have killed 100,000 elephants between 2010 and 2012, as the booming ivory trade takes its toll on the animals in Africa. Video provided by Newsy
Powered by NewsLook.com
Charter Schools Alter Post-Katrina Landscape

Charter Schools Alter Post-Katrina Landscape

AP (Aug. 20, 2014) — Nine years after Hurricane Katrina, charter schools are the new reality of public education in New Orleans. The state of Louisiana took over most of the city's public schools after the killer storm in 2005. (Aug. 20) Video provided by AP
Powered by NewsLook.com
Green Power Blooms as Japan Unveils 'hydrangea Solar Cell'

Green Power Blooms as Japan Unveils 'hydrangea Solar Cell'

AFP (Aug. 19, 2014) — A solar cell that resembles a flower is offering a new take on green energy in Japan, where one scientist is searching for renewables that look good. Duration: 01:29 Video provided by AFP
Powered by NewsLook.com
Disquieting Times for Malaysia's 'fish Listeners'

Disquieting Times for Malaysia's 'fish Listeners'

AFP (Aug. 19, 2014) — Malaysia's last "fish listeners" -- practitioners of a dying local art of listening underwater to locate their quarry -- try to keep the ancient technique alive in the face of industrial trawling and the depletion of stocks. Duration: 02:29 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins