PolarResearch and SupplyVessel POLARSTERN Operated by the Alfred-Wegener-Institute

POLARSTERN, operated by the Alfred-Wegener-Institut Helmholtz-Zentrum für Polarund Meeresforschung, is an ice going research and supply vessel. The main operation areas are the icecovered seas of the northern and southern polar regions. The ship provides ideal working conditions for almost all disciplines of marine sciences, atmospheric and glaciological research. It can break ice up to 2m continuously and can operate up to 90 days at sea. POLARSTERN is therefore ideally suited for often long expeditions to remote polar regions. POLARSTERN regularly supplies the Antarctic research stations, especially the Neumayer Station III and the Kohnen Station (Alfred-Wegener-Institut Helmholtz-Zentrum für Polarund Meeresforschung, 2016a). In the last 35 years POLARSTERN was in average 310 days per year at sea, she is the major research tool of the German polar research programme.


Introduction
RV Polarstern is a research and supply vessel that was commissioned in 1982. It is owned by the German Federal Ministry for Education and Research and is operated by the Alfred-Wegener-Institut. The private shipping company F. Laeisz is responsible for the professional management of the ship. Its home * Cite article as: Alfred-Wegener-Institut Helmholtz-Zentrum für Polar-und Meeresforschung. (2017). Polar Research and Supply Vessel POLARSTERN Operated by the Alfred-Wegener-Institute. Journal of large-scale research facilities, 3, A119. http://dx.doi.org/10.17815/jlsrf-3-163 port is Bremerhaven. The ship is designed for operation in polar waters even during wintertime, and is currently one of the top polar research vessels worldwide, combining good icebreaking properties with a wide range of research capacities. RV Polarstern is equipped for multidisciplinary use and meets the demands of research in biology, geology, geophysics, glaciology, chemistry, oceanography, and meteorology. It has nine scienti c laboratories. Additional laboratory containers can be stowed both on and below deck. Cold storage rooms and aquarium containers make it possible to conduct experiments on board as well as transport of samples and living marine organisms. Extensive hoisting equipment, such as cranes and winches, is available for the deployment of sampling devices. RV Polarstern is equipped with hydroacoustic echo sounders that can be used to conduct measurements at water depths of up to 10,000 meters and up to 150 meters into the sea oor. It is at sea for an average of 310 days per year. In addition to scienti c expeditions, RV Polarstern is part of an international programme to supply the research stations in the Antarctic, making it the most important tool for the supply of the German Neumayer Station III and eld research activities. Supply trips are always combined with scienti c programmes. 2 Technical data and capacities for work in polar regions RV Polarstern is a double-hulled icebreaker that is able to operate in polar regions during the winter months, at temperatures less than -50°C. The ship is powered by four main engines and two variablepitch propellers. Ice thicknesses of up to 1.5 m can be broken at a speed of about 5 knots, while thicker ice is broken by ramming. Table 1 gives an overview of the ship's technical data and capabilities for navigation in ice.
RV Polarstern is equipped with two helicopters (BK117 C-1). They are used for support in cases of emergency, to transport equipment and persons, are used as ying measuring platforms (for ice thickness measurements, for example), and facilitate navigation in ice by nding the fastest and most energye cient routes through the sea ice. The on-board weather station is continuously sta ed with a meteorologist and meteorological technician from Deutscher Wetterdienst, and is able to provide weather forecasts for safe ship and ight operations as well as for the daily expedition planning, even in remote regions. High resolution satellite maps for ice forecasting are obtained on land and stored in an information system used for science and   navigation. RV Polarstern has a well-equipped surgery room and hospital sta ed by a physician and a nurse that proper medical treatment is ensured even in remote areas.

Research capacities
RV Polarstern has a variety of winches and cables, hoisting equipment, laboratories, and laboratory container spaces. Since RV Polarstern was designed to be a ship that can be used to serve as many scienti c disciplines as possible, the labs, containers, and winch con gurations are customised and reorganised according to the needs of the various research groups before an expedition begins.  The permanently installed sensors and instruments on board RV Polarstern are summarised in Table 3. In addition to the instruments required for standard meteorological observations, a range of instruments for measuring water parameters (temperature, salinity, pCO2, nutrients, etc.) are in constant operation and made available to researchers as en route data. Hydroacoustic devices for recording sea oor topography and sediment characteristics, as well as instruments for measurements in the water column are also available. For positioning of devices underwater (ROV, AUV, moorings, etc.), a POSIDONIA system is permanently installed. An additional mobile GAPS system is also available. All incoming data from sensors and instruments, from the weather station, from navigational instruments (ship speed, course, roll and pitch motions, etc.), and ship equipment (e.g. winch parameters) are recorded and stored in a central data logging system (DShip 3) and are available to researchers in each lab and via WLAN in real time. After the expedition, a copy of the data is stored at the Alfred-Wegener-Institut and kept available to scientists even years after an expedition.  Large equipment such as work-class sized ROVs and the MeBo submarine drilling device (MARUM, University of Bremen) are also operated on board RV Polarstern. The infrastructure of this equipment is easily integrated into the ship's infrastructure that large scienti c equipment can also be used in ice-covered regions at high latitudes.

METEOROLOGICAL
4 Applications, use, and access to the infrastructure RV Polarstern operates in the southern and northern polar regions ( Figure 4) and during the last 35 years she has been at sea for an average of 310 days per year. In the Antarctic, the ship's activities have been focused on the Weddell Sea, the Antarctic Peninsula, the Scotia Sea, and the Drake Passage. In the Arctic, work is focused on the Fram Strait, areas o the east coast of Greenland, and the central Arctic Ocean. RV Polarstern is also able to operate in di cult high latitude regions, and has several times been operating at the North Pole. Two winter experiments in the Antarctic have shown that the ship can also be used at very low temperatures (below -50°C, Figure 3) and under di cult ice conditions. During the necessary transit cruises from north to south and back, en route measurements are continued, and the resulting data is made available to science. The scienti c programmes during transit cruises are focused primarily on investigations of the atmosphere and on ocean-atmosphere exchange processes.
In recent years, transit cruises have been increasingly used for student training. RV Polarstern plays an important role both in Germany and internationally to enable access to the polar marine areas. On average, around 30% of the expedition participants come from international partner institutes and around 25% come from domestic institutes and universities outside the Helmholtz Association of German Research Centres. Participation is based on joint scienti c programmes and by secondary users (smaller university research teams, for example). Ship time is granted through a review process that is shared for all large and medium-sized German research vessels. Information on deadlines and the review process is available from a common web portal, which is also used for the submission of applications: https://www.portal-forschungsschi e.de (in German and English).

RV Polarstern as a supply vessel
RV Polarstern is part of an international supply network for Antarctic research stations. The primary partners in this network are Great Britain and South Africa. Without the good icebreaking capacities of RV Polarstern, the regular supply of Neumayer Station III (Alfred-Wegener-Institut Helmholtz-Zentrum für Polar-und Meeresforschung, 2016a) and eld expeditions would not be possible. Around 80 spaces for 20' containers are available on board, which can be stowed both on the foredeck and the front cargo hold. Without helicopter operations, other loading options are available on the helideck. RV Polarstern has additional bunker capacity allowing storage of fuel for stations, vehicle eets, and ight operations, for example for the research aircraft Polar 5 and 6 (Alfred-Wegener-Institut Helmholtz-Zentrum für Polar-und Meeresforschung, 2016b), as well as for international partners.
Supply and waste disposal for Neumayer Station III takes place at the Atka Iceport, directly on the edge of the ice shelf ( Figure 5) in Atka Bay. Both cranes (on the fore and aft parts of the deck, respectively) are used for loading and unloading. Bunker is handed over from the ship to tank containers on the ice edge.