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).
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
Researchers find higher than expected carbon emissions from inland waterways
25.05.2016 | Washington State University
Rutgers scientists help create world's largest coral gene database
24.05.2016 | Rutgers University
A biological and energy-efficient process, developed and patented by the University of Innsbruck, converts nitrogen compounds in wastewater treatment facilities into harmless atmospheric nitrogen gas. This innovative technology is now being refined and marketed jointly with the United States’ DC Water and Sewer Authority (DC Water). The largest DEMON®-system in a wastewater treatment plant is currently being built in Washington, DC.
The DEMON®-system was developed and patented by the University of Innsbruck 11 years ago. Today this successful technology has been implemented in about 70...
Permanent magnets are very important for technologies of the future like electromobility and renewable energy, and rare earth elements (REE) are necessary for their manufacture. The Fraunhofer Institute for Mechanics of Materials IWM in Freiburg, Germany, has now succeeded in identifying promising approaches and materials for new permanent magnets through use of an in-house simulation process based on high-throughput screening (HTS). The team was able to improve magnetic properties this way and at the same time replaced REE with elements that are less expensive and readily available. The results were published in the online technical journal “Scientific Reports”.
The starting point for IWM researchers Wolfgang Körner, Georg Krugel, and Christian Elsässer was a neodymium-iron-nitrogen compound based on a type of...
In the Beyond EUV project, the Fraunhofer Institutes for Laser Technology ILT in Aachen and for Applied Optics and Precision Engineering IOF in Jena are developing key technologies for the manufacture of a new generation of microchips using EUV radiation at a wavelength of 6.7 nm. The resulting structures are barely thicker than single atoms, and they make it possible to produce extremely integrated circuits for such items as wearables or mind-controlled prosthetic limbs.
In 1965 Gordon Moore formulated the law that came to be named after him, which states that the complexity of integrated circuits doubles every one to two...
Characterization of high-quality material reveals important details relevant to next generation nanoelectronic devices
Quantum mechanics is the field of physics governing the behavior of things on atomic scales, where things work very differently from our everyday world.
When current comes in discrete packages: Viennese scientists unravel the quantum properties of the carbon material graphene
In 2010 the Nobel Prize in physics was awarded for the discovery of the exceptional material graphene, which consists of a single layer of carbon atoms...
24.05.2016 | Event News
20.05.2016 | Event News
19.05.2016 | Event News
27.05.2016 | Awards Funding
27.05.2016 | Life Sciences
27.05.2016 | Life Sciences