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57-513: During its one-year-long journey, the central expedition ship, the research icebreaker Polarstern from Germany's Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) , was supported and resupplied by the icebreakers and research vessels Akademik Fedorov and Kapitan Dranitsyn (Russia), Sonne and Maria S. Merian (Germany) and Akademik Tryoshnikov (Russia). In addition, extensive operations involving helicopters and other aircraft were planned. In total, during

114-684: A better understanding of the recycling chains. A closely interlinked modelling and observation concept was central to the definition and planning of the MOSAiC expedition. In order to understand and explain the changes at work in the Arctic climate system , new models will be developed, and previous models will be refined, on the basis of the observations and readings taken during the expedition. These observations will also play an important part in improving these models and developing new ones for weather and sea-ice forecasting , and for climate projections. In turn,

171-477: A line of up to 16 moorings across Fram Strait. The mooring line has been maintained since 1997 with a spacing of roughly 25 km . At up to five different depths, the moored array measures the water velocity, temperature, and salinity of the water column. Computer simulations suggest that 60 to 70% of the fluctuation of the sea ice flowing through the Fram Strait is correlated with a 6–7 year fluctuation in which

228-578: A long-term, efficient and economic vessel. On 20 September 2019 Polarstern sailed from Tromsø , Norway, for a 12 to 14 month-long Multidisciplinary drifting Observatory for the Study of Arctic Climate ( MOSAiC ) expedition across the Arctic. She settled in an ice floe on 4 October 2019. The aim was drifting with this floe, passing the North pole and eventually reaching open water in the Fram Strait . While stuck in

285-671: A maximum depth of 5,550 m (18,210 ft) ±14 m (46 ft)(See also: Litke Deep ). The Yermak Plateau , with a mean depth of about 650 m, lies to the northwest of Spitsbergen. Historically, Fram Strait was home to a large population of Bowhead whales , then called the Greenland right whale . By mid-17th century, the Svalbard population of Bowhead whales was reduced to near extinction by excessive whaling (See also: Whaling in Spitsbergen ; Smeerenburg ). Western Fram Strait may be

342-463: A physical basis for understanding local and vertical interactions in the atmosphere and the interactions between the atmosphere, the sea ice, and the ocean. The characterization of processes in clouds , in the atmospheric boundary layer , surface layer, and surface energy flux will lead to a better understanding of the lower troposphere , which interacts with the surface in the Arctic. Performed heat flux measurements allowed for an accurate estimate of

399-592: A speed of 5 knots (9.3 km/h; 5.8 mph). Thicker ice of up to 3 m (9.8 ft) can be broken by ramming. On 7 September 1991, Polarstern , assisted by the Swedish arctic icebreaker Oden , reached the North Pole as the first conventional powered vessels. Both scientific parties and crew took oceanographic and geological samples and had a common tug of war and a football game on an ice floe. In 2001, Polarstern together with USCGC  Healy reached

456-661: A very thin ice layer. Readings taken at higher altitudes provided insights into the characteristics of the middle and upper troposphere and the interaction with the stratosphere. To improve our understanding of aerosols and aerosol-cloud interactions over the Central Arctic, especially in winter, measurements were taken on the composition of the particles, their physical properties, their direct and indirect radiation effects, and their interactions with cloud properties. Routine radiosonde observations in combination with tethered balloon measurements provided high-resolution profiles of

513-509: A wintering ground for this Critically Endangered population. The use of the name "Fram Strait" for the passage between Spitsbergen and Greenland appears to have come into common use in the oceanographic literature in the 1970s. Fram Strait is named after the Norwegian ship Fram . In an 1893 expedition led by Fridtjof Nansen , the Fram drifted for two years across the Arctic before exiting

570-556: The Akademik Fedorov , proceeded east along the Siberian coast , and at roughly 125° East, turned north and began breaking into the sea ice of the Central Arctic, which was still feasible at that time of year. On 4 October 2019, at a position of 85° North and 134° East, the MOSAiC expedition found a suitable ice floe, which measured roughly 2.5 by 3.5 kilometres. Polarstern put her engines in neutral and allowed herself to become trapped in

627-694: The Arctic Ocean . The northward velocity is maximum in winter, so the heat transport is highest in winter. On the west side of the strait, the East Greenland Current flows southward on the Greenland Shelf. The current carries is relatively cold and fresh water out of the Arctic that corresponds to a water mass called Polar water. The Fram Strait area is located downwind of the Transpolar Drift and therefore covered by multi-year ice in

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684-565: The Arctic ’s role as a global energy sink; how global connection patterns will be shaped by the changing ice volume in the Arctic; and how these changes will affect the circulation and weather in the lower latitudes. The modelling and observations during MOSAiC will be conducted in close cooperation with the international modelling efforts of the World Weather Research Programme and World Climate Research Programme. The first phase of

741-527: The Icelandic Low Pressure system extends eastward into the Barents Sea . The amount of sea ice passing through the Fram Strait varies from year to year and affects the global climate through its influence on thermohaline circulation . The warming in the Fram Strait region has likely amplified Arctic shrinkage , and serves as a positive feedback mechanism for transporting more internal energy to

798-704: The United States ), was conducted by the AWI and was led by the polar and climate researcher Markus Rex and co-led by the atmospheric researcher Matthew Shupe from the University of Colorado Boulder . MOSAiC's main goals were to investigate the complex and still only poorly understood climate processes at work in the Central Arctic, to improve the representation of these processes in global climate models, and to contribute to more reliable climate projections. The expedition cost 140 million euros (approximately 154 million USD); half of

855-489: The biogeochemistry of the net air/ice flow of CO 2 produced by sea ice, and into the potential for capturing organic carbon and the respiration of CO 2 . A second goal was to quantify the methane accumulation, the oxidation below the sea ice, and the air/ocean flows with regard to the potential for major oceanic methane flows into the atmosphere. A third key element: observing the cycles of biogenic gases like N 2 O , O 2 , DMS (dimethyl sulphide) and bromoform in

912-411: The dynamics and thermodynamics of the mixing layer were explored in detail. For this purpose, continuous measurements were taken of turbulent fluxes directly below the ocean-ice boundary, to help understand the speeds of the ice and ocean, vertical thermal and momentum flows, diffusion of mass and other key processes. Moreover, the deep ocean was observed in the broader context by creating profiles of

969-642: The prime meridian . The Greenland and Norwegian Seas lie south of Fram Strait, while the Nansen Basin of the Arctic Ocean lies to the north. Fram Strait is noted for being the only deep connection between the Arctic Ocean and the World Oceans . The dominant oceanographic features of the region are the West Spitsbergen Current on the east side of the strait and the East Greenland Current on

1026-412: The snow , sea ice and water , which contributed to our grasp of the underlying biogeochemical paths. An additional important aspect was the creation of an annual mass balance and ice/water cycle for macro- and micronutrients; in this regard, vertical nutrient flows between the ocean, euphotic zone , mixed and deep layers of the ocean were investigated, in part with the aid of molecular tools, to arrive at

1083-617: The Arctic and Fram Strait is 2545 m deep. The Knipovich Ridge , the northernmost section of the Mid-Atlantic Ridge , extends northward through the strait to connect to the Nansen-Gakkel Ridge of the Arctic Ocean. A rift valley , caused by sea-floor spreading , runs adjacent and parallel to the Knipovich Ridge. The Molloy Deep within Fram Strait is the deepest point of the Arctic. This small basin at 79°8.5′N and 2°47′E has

1140-739: The Arctic over time. Ridge observations revealed that the most of first-year ridge consolidation occurred during the spring season before the melt onset, and was initiated by warm air intrusions and transfer of snow into leads, which was also confirmed by 6%–11% snow mass fraction in ridges. It was also shown, that bottom melt rates for pressure ridges were approximately four times larger than for level ice, while ridge shape also influenced its melt, with higher melt for deeper, steeper, and narrower ridges. The observations included measurements of snow density, mechanical resistance, and microstructure (using computed tomography ), which allowed to compute snow thermal conductivity . Ice mass balance observations included

1197-514: The Arctic through what is now known as Fram Strait. According to glaciologist and geographer Moira Dunbar , an early adopter of the name, the name "Fram Strait" originated in the Russian scientific literature. While in common use, particularly in the oceanographic scientific literature, the name appears to be unofficial. Fram Strait is the only deep-water connection between the World Oceans and

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1254-657: The Arctic. Other gateways are the Barents Sea Opening (BSO), the Bering Strait and various small channels in the Canadian Arctic Archipelago . They are all shallower than Fram Strait, leaving Fram Strait the only route by which deep water can be exchanged between the Atlantic and Arctic Oceans. This exchange occurs in both directions, with specific water masses identified with specific regions flowing between

1311-578: The Central Observatory. After delivering one last load of fuel, at the end of October Akademik Fedorov returned to Tromsø. From this point on, the natural drift carried Polarstern and its network of research stations across the North Pole region. On 24 February 2020, the Polarstern has broken a record: during the drift she reaches 88°36' North, just 156 kilometres from the North Pole. In summer 2020,

1368-486: The Fram Strait." The Alfred Wegener Institute for Polar and Marine Research (AWI) and the Norwegian Polar Institute (NPI) have maintained long term monitoring measurements in Fram Strait to obtain volume- and energy-budgets through this choke point. The observations also serve to assess the development of the Arctic Ocean as a sink for terrestrial organic carbon . The AWI=NPI observing array consists of

1425-415: The MOSAiC project is to understanding the coupled climate processes in the Central Arctic, so that they can be more accurately integrated into regional and global climate models. The findings will contribute to more reliable climate projections for the Arctic and globally, to improved weather forecasts and better Arctic sea ice forecasts. In addition, the outcomes of the MOSAiC mission will help to understand

1482-581: The Oceans. Water with characteristics of the deep Canadian and Eurasian Basins of the Arctic are observed leaving the Arctic in the deep western side of Fram Strait, for example. On the eastern side, cold water from the Norwegian Sea is observed entering the Arctic below the West Spitsbergen Current. In recent years the nature and interactions of these water masses have been changing, symptoms of

1539-474: The atmospheric conditions in the column of air above the MOSAiC site. In addition, radar measurements were used to determine the vertical profile of wind speed and direction as well as key cloud properties, including ice and liquid water content. Key thermodynamic parameters , as well as the kinematic structures of the atmosphere , were investigated with the aid of microwave and infrared radiometers , Raman and Doppler lidar . The sea-ice observations covered

1596-406: The broad range from the physical and mechanical characteristics of Arctic sea ice, to its morphology , optical properties and mass balance . The emphasis was on characterising snow cover and ice cover, and on arriving at a better understanding of the processes that determine their properties. Snow trenches (pits) and ice cores helped the researchers gather this valuable data. Further aspects of

1653-548: The budget was provided by the German Federal Ministry of Education and Research (BMBF). U.S. participation was primarily supported by the National Science Foundation , which contributed roughly $ 24 million to the project, among the largest Arctic research initiatives the agency has ever mounted. The U.S. Department of Energy was also highly invested in the mission, funding nearly $ 10 million and providing

1710-582: The changes occurring with the ocean's climate. Warm, salty water is transported northward from the Atlantic by the West Spitsbergen Current in the east of the strait. The West Spitsbergen Current is the northernmost branch of the North Atlantic Current system. This water forms a water mass called the Atlantic water. The sub-surface flow has a strong seasonality with a minimal volume transport in winter. This current transports internal energy into

1767-407: The energy balance in the Arctic, as well as the growth and melting of sea ice due to additional warmth. They also play an important role in the biological activity that binds and potentially exports CO 2 . Measurements from the water column will shed new light on key mechanisms occurring in the ocean, e.g.: (1) heat exchange between sea ice and ocean , (2) absorption of sunlight and processing of

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1824-587: The expedition featured a six-week course for 20 postgraduate students aboard Akademik Fedorov . This was jointly delivered by MOSAiC Partners and the Association of Polar Early Career Scientists . RV Polarstern RV Polarstern (meaning pole star ) is a German research icebreaker of the Alfred Wegener Institute for Polar and Marine Research (AWI) in Bremerhaven , Germany . Polarstern

1881-549: The first time the Fram ’s drift was repeated with a research icebreaker, equipped with a veritable arsenal of cutting-edge instruments for exploring and recording the complex climate processes in the Central Arctic. The heart of MOSAiC was the Polarstern ’s one-year-long drift through the Central Arctic. On 20 September 2019 the ship departed from the Norwegian port of Tromsø together with

1938-461: The flow speed, temperature, salinity and dissolved oxygen in the top hundred metres of the Arctic Ocean on a regular basis, so as to better grasp its effects on the upper ocean-ice boundary layer. The observations on biological and biogeochemical transformation and succession mainly focussed on analysing samples from all three major physical regimes, i.e., the ice, snow and water environments. Additionally flow measurements were conducted at both

1995-522: The ice in March 2020, a member of the aircraft team who had not yet joined the ship in the Arctic tested positive for COVID-19 . This resulted in the entire aircraft team being placed in isolation in Germany and caused delays in the retrieval of scientific data from around the ship to provide context to the data taken aboard. After 389 days, this 2019 – 2020 arctic expedition successfully ended on 12 October 2020 when

2052-457: The ice/water and ice/air boundary layers. These were repeated throughout the entire Arctic year in order to quantify the biology and biogeochemistry of the sea-ice/atmosphere system at every time of year, especially in the under-researched Arctic winter. For example, the annual mass budget for organic and inorganic carbon was monitored, and crystallographic readings were taken on the ikaite in seafloor channels. The latter offered insights into

2109-569: The installation of buoys measuring sea ice temperature , as well as ablation stakes, measuring the evolution of sea ice surface and bottom interfaces. Additionally, sea ice thickness was measured using ground-based electromagnetic sounding, while snow and sea ice freeboard were measured using helicopter-based laser scanner. Additionally, underwater sea ice topography and other physical parameters were measured using observations from remotely operated vehicle , as well as biophysical characterization of algae habitats. Winter observations were characterized by

2166-420: The largest suite of atmospheric instruments. In the half-year-long Arctic winter, the sea ice is too thick for research icebreakers to penetrate. Consequently, data from the Central Arctic is virtually non-existent, particularly during winter. For reaching the Central Arctic in winter, the MOSAiC expedition followed in the footstep of Fridtjof Nansen's famous expedition with the wooden sailing ship Fram in

2223-432: The models will offer insights into phenomena that are not directly observable. The observations made throughout MOSAiC will provide new framework conditions for models at various scales; e.g. high-resolution models will be used for detailed studies, and these studies can provide the basis for improving regional and global climate models. In addition, regional Arctic models will be used to answer important questions concerning

2280-661: The platform portal of the Alfred Wegener Institute (AWI) for Polar and Marine Research. The ship plays a central role in German musician Schiller's 2010 album Atemlos ( German for breathless ). A track is titled after the ship. It is also featured in the DVD of the same title, showing the musician's expedition on the vessel. Fram Strait The Fram Strait is the passage between Greenland and Svalbard , located roughly between 77°N and 81°N latitudes and centered on

2337-534: The pole again. She returned for a third time on 22 August 2011. This time she reported the most frequently recurring ice thickness at 0.9 m (2 ft 11 in) compared with 2 m (6 ft 7 in) in 2001. On 2 March 2008, one of the vessel's helicopters crashed on a routine flight to the Antarctic Neumayer II base. The German pilot and a Dutch researcher were killed, and three other passengers were injured. On 17 October 2008, Polarstern

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2394-449: The presence of platelet ice due to the presence of supercooled water, while summer melt was characterized by meltwater stratification and formation of false bottoms which covered around 20% of sea-ice area. Aerial observations of surface temperature revealed a strong 41% preconditioning of surface melt ponds, which form in the areas of warm surface temperature anomalies in winter, typical for thin ice and snow. Ocean processes influence

2451-479: The regional and global effects of Arctic climate change and the loss of sea ice. They will improve the preparedness of communities in the Arctic and northern mid-latitudes, provide the scientific basis for the development of policies for a sustainable development of the Arctic and support fact based decision-making in the areas of mitigation of and adaptation to global climate change. The comprehensive and complex atmospheric measurements carried out during MOSAiC provide

2508-630: The research vessel safely returned to its home port of Bremerhaven, Germany. A revised request for bids for a replacement, reflecting changes in technology since the first was issued, was expected, with Polarstern II possibly ordered in 2022 to enter service in 2026 or 2027. The new vessel could cost over €800m, and could include hybrid diesel-electric propulsion, integrated under-water robotic systems and several helicopter landing options. Current listings of all cruises on board Polarstern as well as associated contents (e.g., tracklines, weekly reports, cruise reports, publications and data) are presented on

2565-401: The resulting heat , (3) interaction with deep sea processes, and (4) primary biological productivity and export of organic matter from the euphotic zone . Given that understanding the evolution of sea ice was one of the primary goals of the MOSAiC expedition, ocean processes affecting the ice, like near-surface mixing, were at the heart of the oceanographic investigations . In addition,

2622-414: The sea ice and atmosphere over the Arctic Ocean, supplementing the MOSAiC expedition's research programme. Fuel depots set up on islands off the coast of Siberia specifically for the expedition supported potential emergency operations by long range helicopters, which were able to reach Polarstern in the event of an emergency at least during the early and late phases of the expedition. The primary goal of

2679-448: The sea ice observation included determining the mass budget by measuring the depth of snow cover and ice thickness, as well as measuring the diffusion of sunlight in the ice, the ice's spectral albedo , and its transmission . In addition, various types of ice ( pressure ridges , first- and second-year level ice) were monitored throughout the entire annual cycle in order to determine the spatial variability and development of ice cover in

2736-417: The sea ice. An extensive research camp was then set up all around the ship on the ice. At the same time, Akademik Fedorov deployed a network of research stations on the ice, some as far as 50 km from Polarstern ’s position. The network consisted of both autonomous and remote-controlled instruments, which were checked at regular intervals using helicopter flights from the central Polarstern, which formed

2793-486: The ship reached the Fram Strait . On 13 August, after a last big refueling and personnel rotation, Polarstern started steaming towards the Central Arctic to study the onset and early freezing phase of the sea ice. On 19 August, the ship reached the North Pole. The journey from the northern Fram Strait to the Pole only took six days to complete. After a short search, the MOSAiC team found a new ice floe. The so-called MOSAiC floe 2.0

2850-421: The surface skin temperature, which showed a substantial bias of those measurements (of 1–3°C during January–April) in comparison with uncoupled atmospheric reanalyses ( ERA5 and JRA-55). One of the greatest challenges was carrying out these measurements consistently throughout the sea ice’s entire annual cycle, especially at the beginning of the freezing period, so as to monitor the transition from open water to

2907-519: The various phases of the expedition, more than 600 people were working in the Central Arctic. The international expedition, which involved more than 80 institutions from 20 countries ( Austria , Belgium , Canada , China , Denmark , Finland , France , Germany , Italy , Japan , the Netherlands , Norway , Poland , Russia , South Korea , Spain , Sweden , Switzerland , the United Kingdom , and

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2964-488: The west of the strait, next to the coast of Greenland . Approximately 90% of sea ice exported from the Arctic is transported by the East Greenland Current. (Sea ice essentially corresponds to fresh water, since its salt content of 4 per mil is much less than the 35 per mil for sea water.) A 2019 estimate states that about "80% of the water exchanged between the Arctic ice cap and the world’s oceans passes through

3021-460: The west. Fram Strait is the northernmost ocean area having ice-free conditions throughout the year. The width of the strait is about 450 km, but because of the wide continental shelves of Greenland and Spitsbergen, the deep portion of Fram Strait is only about 300 km wide. The ocean over the Greenland continental shelf is often covered with ice. Within Fram Strait, the sill connecting

3078-429: The years 1893–1896, over 125 years ago. His daring voyage showed that it was possible to let a ship drift across the polar cap, from Siberia to the Atlantic, stuck in the thick sea ice and solely driven by the forces of the natural drift of the ice. Though Nansen has demonstrated the fundamental feasibility of such an endeavour, the scientific measurements possible in his days were still quite rudimentary. During MOSAiC, for

3135-508: Was built by Howaldtswerke-Deutsche Werft in Kiel and Nobiskrug in Rendsburg , was commissioned in 1982, and is mainly used for research in the Arctic and Antarctica . The ship has a length of 118 metres (387 feet) and is a double-hulled icebreaker. She is operational at temperatures as low as −50 °C (−58 °F). Polarstern can break through ice 1.5 m (4 ft 11 in) thick at

3192-475: Was discovered eleven nautical miles from the route that the original floe took in January 2020. Polarstern left the MOSAiC floe 2.0 on 20 September 2020, one year after the start of the expedition. On 12 October 2020, the Polarstern returned to her homeport in Bremerhaven . During the period August/September 2020, the German research aircraft Polar 5 and Polar 6 took off from Spitsbergen to conduct aerial surveys of

3249-531: Was the first research ship ever to travel through both the Northeast Passage and the Northwest Passage in one cruise, thus circumnavigating the North Pole. The German government in 2015 issued a request for bids on the construction of a replacement for Polarstern , but did not award a contract and eventually withdrew the request in early 2020 as it no longer covered current technological demands for

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