Arctic Sea ice: Microstructure and geophysical processes Dr Hajo Eicken, Scientific Director of the Alfred Wegener Institute. Sea ice snow Arctic glaciology Sea-ice geophysics is a central research field [...] changes and ocean currents. Although these processes occur on very small spatial scales, they strongly affect the growth, stability, and decay of sea ice and thereby influence both Arctic ecosystems and [...] field within polar and climate sciences. Sea ice covers large parts of the Arctic and Antarctic and plays a key role in the Earth system by linking physical, ecological, and climatic processes. A particular

analyses is to determine how much carbon the ocean removed from the atmosphere and stored in its depths in the past. The permanently frozen soils of the Arctic store tremendous amounts of carbon in the form [...] not consumed by marine animals, including dead marine microorganisms, material transported to the oceans by rivers –the particles that trickle down are deposited layer by layer at depth. Ultimately, a unique [...] deposited on the seafloor, leaving clues that enable the AWI geoscientists not only to reconstruct the Arctic’s climate history, but also to understand the role of thawing permafrost in past climate changes.

patterns and linkages. Establishment of sea surface temperature and sea ice records for the Arctic and Southern Ocean covering the MIS 5e warm interval. [...] latitudes are particularly sensitive and vulnerable to future global warming. The potential of polar oceans and their marginal seas to amplify on a global scale warm climate conditions and sea level change

coupled Arctic climate system with the overall aim to (i) improve our understanding and model representation of key climate processes in the Arctic and (ii) to improve our understanding of Arctic – midlatitude [...] the observed drastic Arctic climate changes and the uncertainty in Arctic climate projections is large. That arises, in large part, from gaps in our understanding of key Arctic processes and feedbacks [...] national and international research projects, such as AC3 , REKLIM , Arctic CORDEX , PolarRES , and WarmWorld . Background The phenomenon of Arctic amplification has a suite of causes, which include various i

the Alfred Wegener Institute’s flagship has successfully completed more than 130 expeditions to the Arctic and Antarctic and offered a temporary home for thousands of researchers from Germany and around the [...] safely traversed 1.8 million nautical miles. The ship is currently on an expedition in the Southern Ocean.

the thickness of the Arctic sea ice is steadily declining and meltwater pools are increasingly forming in summer, covering large areas of the Arctic sea ice, both the ice and the ocean below absorb more solar [...] between the ocean and atmosphere sea ice modulates the flow of energy, kinetic force, salt, moisture and trace gases between the two components. Though our knowledge of the sea ice in the Arctic and Antarctic [...] data are needed in order to validate our computer models and depict the realities of sea ice in the Arctic and Antarctic as precisely as possible using computers. If we succeed in this detail work, we’ll

Due to intensifying sea-ice melting in the Arctic, sunlight is now penetrating deeper and deeper into the ocean. Since marine zooplankton respond to the available light, this is also changing their behaviour

sea surface temperature observations to constrain upper ocean properties in an Arctic sea ice-ocean data assimilation system. J. Geophys. Res. Oceans , 124, 4723-4743, doi:10.1029/2019JC015073 Pradhan, H [...] ed-grid ocean model under Earth System Modeling Framework, Ocean Modelling , 196, 102546, ​ doi:10.1016/j.ocemod.2025.102546 . Bunsen, F. , J. Hauck, L. Nerger , S. Torres-Valdés. (2025) Ocean carbon sink [...] (2018) Arctic-wide sea-ice thickness estimates from combining satellite remote sensing data and a dynamic ice-ocean model with data assimilation during the CryoSat-2 period. J. Geophys. Res. Oceans , 123

flux in polar oceans In both Polar Regions, areas covered by sea ice are shrinking due to climate warming. What are the consequences of sea ice decline in the Arctic and the Antarctic Ocean? Answering this [...] and nature conservation in the Arctic and Antarctic Oceans under environmental change. The research project investigates ice-covered deep-sea ecosystems in the Arctic and Antarctic sea ice zones. Iceflux

Polarstern returns from the “Trans-Arctic Survey of the Arctic in Transition” (TransArc) expedition, intended to record physical, biological and chemical changes in the Arctic Ocean. One highlight of the expedition: [...] 2012-10.2012 – During the Polarstern’s 27th stay in the Arctic and in the context of the “Sea ice - ocean - seafloor interactions in the changing Arctic” (IceAr) expedition, e.g. long-term changes in this [...] on yet another Arctic expedition – its 29th. The expedition, officially designated “Transitions in the Arctic Seasonal Sea Ice Zone” (TRANSSIZ), was planned by the international “Arctic in Rapid Transition”