Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Research vessel Polarstern returns home after one and a half years in the Antarctic

11.04.2014

After one and a half years in the Antarctic the research vessel Polarstern is expected back in its home port on 13 April.

Apart from the crew and scientists on board, there are lots of data, samples and animals from the Southern Ocean that will soon be examined more closely in the laboratories of the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI).


Deployment of measuring buoys on ice floes.

© S. Schwegmann / Alfred Wegener Institute

They stem from the area of the Filchner-Ronne Ice Shelf in the very south of the Weddell Sea, where scientists conducted research on sea ice, oceanic currents and the biocoenoses on the last Antarctic cruise leg of the expedition.

Polarstern covered over 64,000 nautical miles in the past 18 months, which corresponds to about 120,000 kilometres and thus three times the circumference of the Earth at the equator. However, the icebreaker sailed through these tropical regions only on the way there and back. The main research area was the Antarctic Weddell Sea. The last expedition prior to the return to Bremerhaven again took the vessel to the very south of Antarctica, to the marine region off the Filchner-Ronne Ice Shelf.

“Even in the Antarctic summer this area is not easily accessible and we had to struggle with very difficult ice conditions,” reports Dr. Rainer Knust, head of the expedition and biologist at the Alfred Wegener Institute. He coordinated a multidisciplinary team from eleven countries on board that conducted investigations on sea ice physics, hydrography and biology.

In close consultation with the captain, Knust laid down the work programme according to the ice conditions. The sea ice physicists were thus delighted about large ice floes on which they were able to place their measuring buoys. The latter measure whether an ice floe is growing or thawing and how quickly and in what direction it is drifting. The installed measuring buoys remain on the ice floes and transmit their data via satellite to the Alfred Wegener Institute in Bremerhaven.

The oceanographers were dependent on gaps in the ice to make use of their devices. They were able to conduct extensive oceanographic measurements of water depth, salinity, temperature and oceanic currents in the research area. In addition to these measurements directly on board, they recovered long-term moorings and deployed new ones. They record oceanographic measurements over a period of more than two years. In this way it is possible to continuously measure changes in salinity and temperature of the seawater. The objective of this work is to record and monitor the very cold melt water plume from the Filchner-Ronne Ice Shelf and its mixing with warmer water from the deeper Weddell Sea.

The work of the oceanographers is supported by Weddell Seals equipped with sensors and transmitters during the expedition. They not only supply measurements on diving behaviour during their dives, but also data on the salinity and water temperature under the ice that cannot be obtained otherwise. These data, too, are transmitted to AWI via satellite. The initial results on the biocoenoses in this still extensively unexplored region show that settlement and species diversity on the seafloor are closely connected with the ice cover and hydrography. Wherever very cold water flows out or in areas that are covered with sea ice for a very long time, species diversity and settlement density are considerably lower than in open regions that are not as greatly influenced by glacier runoff.

“Earlier findings concerning the unexpected occurrence of elephant seals on the northern shelf slope of the Filchner Trench gave the impetus to study in more detail the previously only presumed connection between hydrographic conditions and increased food supply for seals in the course of our expedition with Polarstern,” reports Knust. Prior to RV Polarstern, AWI’s research aircraft Polar 6 was also in operation on the edge of the Filchner-Ronne Ice Shelf in order to record the number of seals from the air. Using Polarstern’s on-board helicopters, biologists also undertook aerial counts. Their first impression before detailed evaluation appears to substantiate the hypothesis that there is indeed a connection between seal numbers and oceanographic conditions.

The Filchner-Ronne Ice Shelf is the second largest ice shelf in Antarctica. Coupled ocean-atmosphere model calculations at AWI indicate that dramatic changes with 20-fold higher melting rates can be expected there at the end of this century. “This expedition is the first of a series of further Polarstern voyages aimed at gaining an understanding of the actual state of the Filchner-Ronne Ice Shelf system and measuring the water masses off and under the ice shelf. Then we will compare them to the little historical data available and can then check the calculated models,” says the head of the hydrographic team on board, Dr. Michael Schröder from AWI. The future expeditions in this region will also be carried out on a multidisciplinary basis in order to examine the connection between ice, seawater and biology.

Polarstern will undergo scheduled maintenance and repair work at the Lloyd shipyard in the coming weeks before the Arctic season begins in mid-May.

Notes for Editors:

We will be glad to provide you with video material on the expedition on request. Please find printable images at http://www.awi.de/en/news/press_releases/.

Your contact persons are Dr. Rainer Knust (tel.: 0049 471 4831-1709, e-mail: Rainer.Knust(at)awi.de) and Dr. Folke Mehrtens, Dept. of Communications and Media Relations (tel.: 0049 471 4831-2007; e-mail: Folke.Mehrtens(at)awi.de).

Follow the Alfred Wegener Institute on Twitter and Facebook. In this way you will receive all current news as well as information on brief everyday stories about life at the institute.

The Alfred Wegener Institute conducts research in the Arctic, Antarctic and oceans of the high and mid-latitudes. It coordinates polar research in Germany and provides major infrastructure to the international scientific community, such as the research icebreaker Polarstern and stations in the Arctic and Antarctica. The Alfred Wegener Institute is one of the 18 research centres of the Helmholtz Association, the largest scientific organisation in Germany.

Ralf Röchert | idw - Informationsdienst Wissenschaft
Further information:
http://www.awi.de

More articles from Earth Sciences:

nachricht Predicting unpredictability: Information theory offers new way to read ice cores
07.12.2016 | Santa Fe Institute

nachricht Sea ice hit record lows in November
07.12.2016 | University of Colorado at Boulder

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>