fluxes in ice covered oceans (Photo: Stefanie Arndt, AWI) The radiation budget of sea ice dominates the sea-ice energy balance and the exchange of energy between the atmosphere and the ocean in ice-covered regions [...] comprehensive data sets from remote regions of the Arctic and Antarctic. Contact: Dr. Marcel Nicolaus Dr. Ran Tao Surface albedo of ice-covered regions in the Arctic and Antarctic mostly depends on the thickness [...] to the atmosphere (albedo), that is absorbed by snow and sea ice, ant that is transmitted into the ocean (transmittance). We perform various radiation measurements during our field campaigns using Polarstern

in various research areas: Climate and Geoscience (atmosphere, ocean, ice and land), Coastal and Shelf Sea Systems, Terrestrial Arctic Ecosystems and Permafrost, Marine and Polar Life, Aquaculture, Bionics

with the atmosphere and ocean. (Antarctic) Climate change Improved snow process formulations in climate models Investigation of the impact of changing atmospheric and oceanic processes on the evolution [...] S. , and Meyer, H.: Isotopic signatures of snow, sea ice, and surface seawater in the central Arctic Ocean during the MOSAiC expedition, Elementa: Science of the Anthropocene, 12, doi.org/10.1 [...] research will significantly improve our process understanding of Antarctic sea ice in the Southern Ocean climate system – from today’s perspective and for future warming climate scenarios. Background Snow

Siberian river systems into the central Arctic and the North Atlantic. This material affects Arctic biogeochemistry and ecosystems, while the fresh water itself alters ocean circulation. The Alfred Wegener Institute [...] suspended matter from the Siberian shelves across the central Arctic towards the Fram Strait channel, which connects to the Nordic Seas. This cross-Arctic flow influences the delivery of both natural substances [...] known as the Transpolar Draft, operates. It also uncovers the various factors controlling this major Arctic surface current, including warmer temperatures which could increase the spread of human-made pollutants

parameters in the ice-covered, central Arctic Ocean. The concurrent recording of physical, biological and biogeochemical measurements in the atmosphere, sea-ice and ocean for time periods of several months [...] observatory (Graphic: Alfred-Wegener-Institut) The properties of the atmosphere, sea-ice and the polar oceans, and feedbacks between these domains play an important role in global climate. At the same time, [...] Nicolaus @ awi.de Prof. Dr. Benjamin Rabe +49(471)4831-2403 Benjamin.Rabe @ awi.de Deployment of an ocean profilers in the sea-ice (Photo: Alfred-Wegener-Institut)

Observations in the Arctic Ocean The Arctic is an environment where global climate change is strongly manifested. The Arctic Amplification, represented by the atmospheric warming trend in the Arctic being about [...] deep oceans. We explore the importance of physical processes in the Arctic and Antarctic Oceans for a changing climate and the polar ecosystems. Polarstern in der Arktis / Polarstern in the Arctic Contact [...] Hoppmann @ awi.de Our Team Main research topics of our group Physical Oceanography of the Arctic Ocean The Arctic Ocean and the Nordic Seas are integral parts of the Atlantic meridional overturning circulation

pigments in the changing Arctic Ocean, Ph.D. thesis, University of Bremen, DOI: 10.26092/elib/6052. 2021 Oelker J. (2021) Suitability of atmospheric satellite sensors for ocean applicaitons . PhD Thesis [...] (2024) Marine Big Data-driven Machine Learning Based Monitoring of Phytoplankton Groups in the Arctic Ocean . Department of Physics and Engineering, University Bremen, Bremen, Germany, Bremen, 12 Sep 2024 [...] 0 Pefanis, V. (2021) Loading of coloured dissolved organic matter in the Arctic Mediterranean Sea and its effects on the ocean heat budget, Ph.D. thesis, University of Bremen, DOI: 10.26092/elib/646. 2016

The winter growth period for sea ice in the Arctic Ocean is now over, with levels at a record low. The winter ice extent on 21 March 2025 was lower than at any time since continuous satellite recording [...] cover is over a million square kilometres below the long-term average. As in February 2025, average Arctic sea ice cover remained at an all-time low for the entire month of March, equalling the previous low

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 [...] unstructured-grid ocean model under Earth System Modeling Framework, Ocean Modelling, 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

degradation and impacts of contaminants of emerging concern (CECs) in the oceans through case studies in the Atlantic, the Arctic and the Mediterranean. It is developing new methods for assessing the impact [...] on, aggregation, ecological function and distribution of organic compounds in the changing polar ocean. We aim to understand the function of marine organic compounds, both, as diagnostic markers to decode [...] for DOM characterization, which allows direct injection of original (i.e., non-extracted), filtered ocean water samples at native salt and DOC concentrations. To achieve this, we used reversed-phase liquid