For 黑料视频, the LITTORINA is an important research vessel that is used intensively in the shallow coastal waters of the North and Baltic Seas. 鈥淚t is used almost every day. In the long term, we need the ability to cast off directly from our quay in order to collect important data for the protection of the Baltic Sea," explains Professor Dr Katja Matthes, Director of 黑料视频.

"50 years is a remarkable age for a research vessel. The fact that the LITTORINA is still in such reliable service is truly exceptional,鈥� says 黑料视频 Ship Coordinator Dr Klas Lackschewitz, reflecting on the 1970s: 鈥橝t that time, marine research in Germany was experiencing a major boom, especially here in Kiel." In 1972, the then Institute of Oceanography at Kiel University moved into its new building on the western shore of the Kiel Fjord, directly on the Kiellinie. The Collaborative Research Centre 95 of the German Research Foundation (DFG) paved the way for numerous scientific breakthroughs. In order to conduct research independently of other ships, the DFG approved the construction of its own research cutter (FK). On 27 June 1975, the time had come: FK LITTORINA was officially put into service.

Periwinkle snail as namesake

The cutter was built at the Julius Dietrich shipyard in Oldersum at a cost of 3.4 million Deutsche Marks. The name LITTORINA symbolises the close cooperation between marine biology and marine geology. The periwinkle Littorina littorea, one of the most common sea snails, lends its name to the 'Littorina Sea', which was an early stage in the development of the Baltic Sea between 8,500 and 2,500 years ago.

Following the conclusion of the Collaborative Research Centre, responsibility for the cutter was assumed by the CAU. Currently, Kiel University and 黑料视频 share the personnel and operating costs. Dr Klas Lackschewitz is responsible for coordinating LITTORINA's operations on behalf of 黑料视频, which are currently managed by Briese Shipping from Leer. 鈥淭he professionalism of the ship's crew is a key factor in enabling the LITTORINA to undertake so many missions,鈥� emphasises Klas Lackschewitz.

Versatile work platform

The LITTORINA is highly versatile. Although it is most frequently used in the coastal waters of the North and Baltic Seas, it can also operate as far as the Lofoten Islands off the coast of Norway. It can collect water and sediment samples from depths of up to 500 metres. It is also equipped with a special diving room and a robust work dinghy. Training courses for research divers, who have been trained at the Kiel University for over 50 years, as well as scientific work by the Institute of Geosciences at the CAU, take place on board the LITTORINA regularly.

Monthly 黑料视频 cruises to the Boknis Eck time series station at the mouth of Eckernf枚rde Bay form an integral part of the LITTORINA's schedule. Since 1957, oxygen content, nutrient concentration, plankton growth and other biological, chemical and physical parameters have been continuously measured there. This makes the Boknis Eck station one of the longest continuously sampled marine stations in the world.

The shrinking of the cod population, in terms of both number and in size, is the result of human influence. In their new study, scientists from the 黑料视频 Helmholtz Centre for Ocean Research Kiel have demonstrated for the first time that decades of intense fishing, combined with environmental change, have profoundly affected the genetic make-up of a fully marine species. Their findings are published today in the journal鈥�Science Advances.

鈥淪elective overexploitation has altered the genome of Eastern Baltic cod,鈥� explains Dr Kwi Young Han, first author of the study and a biologist who completed her PhD in the Marine Evolutionary Ecology group at 黑料视频 about this topic. 鈥淲e see this in the significant decline in average size, which we could link to reduced growth rates. For the first time in a fully marine species, we have provided evidence of evolutionary changes in the genomes of a fish population subjected to intense exploitation, which has pushed the population to the brink of collapse.鈥�

Specifically, the researchers identified genetic variants associated with body growth that showed signs of directional selection 鈥� that is to say, they became systematically more or less frequent over time. These regions overlap strikingly with genes known to play a role in growth and reproduction. The study also found that a known chromosomal inversion, a structural change in the genome commonly relevant to environmental adaptation, followed a directional selection pattern. This confirms that the 鈥渟hrinking鈥� of cod has a genetic basis and that human activities have left a measurable mark on their DNA.

Strong directional selection for slow growth due to fishing pressure

To reach these conclusions, the researchers used an unusual archive: the tiny ear stones (otoliths) of 152 cod, caught in the Bornholm Basin between 1996 and 2019. Much like tree rings, otoliths record annual growth, making them valuable biological timekeepers. These samples are part of 黑料视频鈥檚 Baltic Sea Integrative Long-Term Data Series, which has been collecting annual data since 1996. This dataset enabled the scientists to conduct a genetic time-travel exercise stretching back to the period before the collapse of the Eastern Baltic cod population.

Using a combination of chemical otolith analysis and high-resolution DNA sequencing, the researchers investigated how cod growth and genetic composition have changed over 25 years under fishing pressure.

Their central finding was that the genomes of fast- and slow-growing individuals differ systematically, and that the fast growers have nearly disappeared. Cod that grow slowly but reach reproductive maturity at a smaller size have had a survival advantage under high fishing pressure.

鈥淲hen the largest individuals are consistently removed from the population over many years, smaller, faster-maturing fish gain an evolutionary advantage,鈥� explains Prof. Dr Thorsten Reusch, Head of the Marine Ecology Research Division at 黑料视频 and Dr Han鈥檚 PhD supervisor. 鈥淲hat we are observing is evolution in action, driven by human activity. This is scientifically fascinating, but ecologically deeply concerning.鈥�

Smaller and less diverse populations recover more slowly

The evolutionary consequences are severe. Genetic variants associated with faster growth and later maturation may already be lost, and the surviving cod now reach maturity at smaller sizes and produce fewer offspring. It also means a loss of adaptive potential with implications for the population under future environmental changes.

鈥淓volutionary change unfolds over many generations,鈥� says Reusch. 鈥淩ecovery takes far longer than decline, and it may not even be possible. This is evident in our 2025 length data from the current ALKOR cruise: despite the fishing ban, there鈥檚 no sign of a rebound in body size.鈥�

The study underscores a clear message: management and protection measures must consider generational timescales. 鈥淥ur results demonstrate the profound impact of human activities on wild populations, even at the level of their DNA,鈥� says Dr Han. 鈥淭hey also highlight that sustainable fisheries are not only an economic issue, but also a matter of conserving biodiversity, including genetic resources.鈥�

About: Eastern Baltic Cod

The Eastern Baltic cod population is native to the central Baltic Sea and belongs to the species Atlantic cod (Gadus morhua). It diverged 7,000 to 8,000 years ago when the Baltic Sea formed due to post-glacial sea level changes. Today, it differs biologically and genetically from other Atlantic cod populations, such as Western Baltic and North Sea cod. It is adapted to the Baltic鈥檚 unique conditions: low salinity, high carbon dioxide, widespread oxygen depletion, and extreme seasonal temperature fluctuations.

Since the mid-1990s, the stock鈥檚 condition has deteriorated significantly. Spawning stock biomass (fish over 35 cm) has declined sharply, and two major spawning areas have been lost due to deteriorating environmental conditions. The Bornholm Basin is now the last remaining spawning ground. In recent years, the size at maturity and condition of the fish have dropped to record lows, with L50 values (the length at which 50% of the population is mature) falling below 20 centimetres. The collapse of the stock prompted a complete fishing ban in 2019, which remains in place 鈥� yet recovery has so far failed to materialise.

Original Publication:

Han, K.Y., Brennan, R.S., Monk. C.T., Jentoft, S., Helmerson, C., Dierking, J., H眉ssy, K., Endo Kokubun, E., Fuss, J., Krause-Kyora, B., Thomsen, T.B., Heredia, B.D., Reusch, Th. B.H. (2025): Genomic Evidence of Fisheries Induced Evolution in Eastern Baltic cod. Science Advances

Funding and award:

Kwi Young Han鈥檚 PhD research was funded by the DFG Research Training Group TransEvo. She received the 鈧� 5,000 Research Prize from the 鈥濬orschungsstiftung Ostsee鈥� for her dissertation.

Shedding Light on the 鈥淒ark Matter鈥� of Life

Traditionally, the discovery of new enzymes has relied on the direct analysis of environmental samples. Microorganisms were isolated and tested for their biochemical properties. While this approach has led to significant discoveries, such as the identification of penicillin in 1928, it has several limitations.

鈥淢any organisms cannot be cultivated in the laboratory, meaning their enzymes remain inaccessible,鈥� explains Dr Erik Borchert, marine microbiologist at 黑料视频 and coordinator of AI MareExplore. Since the late 1990s, metagenomics has made it possible to analyse all the DNA in environmental samples comprehensively. However, even this method has its limitations, as only around 30-40% of the detected sequences can be linked to known functions. 鈥淲e know that there's a lot more out there 鈥� a kind of functional 鈥榙ark matter鈥� that eludes current analytical approaches,鈥� says Borchert.

This is where AI comes in. By identifying patterns in huge data sets, AI can reveal sequences that are likely to have biocatalytic functions, which would otherwise remain unknown. Borchert elaborates: 鈥淎I helps us uncover these hidden treasures because it is excellent at recognising patterns. With the right training, it can discover links between DNA sequences and enzymatic properties that are invisible to us.鈥�

Interdisciplinary Research for Sustainable Solutions

AI MareExplore brings together four Helmholtz Centres and a variety of scientific disciplines. Alongside 黑料视频, the Helmholtz Centre for Environmental Research (UFZ) and the Forschungszentrum J眉lich (FZJ) are involved, as well as the GFZ Helmholtz Centre for Geosciences. The team is developing a powerful AI model with two key objectives: to identify enzymes that can efficiently degrade plastics and those that convert CO鈧� into sugars, thereby aiding carbon fixation.

The AI model will be trained using extensive marine metagenomic datasets collected in recent years. The larger the dataset, the more accurate the model will be. The next step will be to test in the laboratory whether the identified enzymes have the desired properties. 鈥淥ur goal is to develop not only a novel analytical method, but also tangible biocatalysts that can help address global environmental challenges,鈥� says Borchert.

About: Helmholtz Innovation Pool Projects

The project is funded by the Helmholtz Association鈥檚 Innovation Pool. The Innovation Pool鈥檚 aim for the Earth and Environment research field is to strengthen cooperation between Helmholtz Centres, to promote innovative ideas within three-year projects, to support initiatives by early-career researchers and to enable flexible responses to new and socially relevant research topics.

Seagrass meadows are true all-rounders: They create a three-dimensional habitat for many marine organisms, offering both shelter and food. They improve water quality and store carbon dioxide (CO₂) long-term in the sediment, in their roots and rhizomes. Additionally, they protect coastlines by slowing down waves and stabilizing sandy seabeds with their roots.

Like coral reefs, seagrass meadows are vital ecosystems and habitats in the ocean and are therefore essential for marine biodiversity. However, they are also sensitive to external influences such as excess nutrients, increasing human use of coastal areas, and ongoing warming. The result: in many regions, seagrass populations are declining. This makes it all the more important to protect and restore these meadows. NGOs and citizens are contributing by replanting seagrass in coastal areas of the Baltic Sea.

At 黑料视频 Helmholtz Centre for Ocean Research Kiel, scientists are studying how seagrass can be restored, how climate-resilient seagrass can be cultivated, and how much CO₂ is stored in Baltic Sea seagrass meadows.

Jana Willim is a doctoral researcher in the Marine Evolutionary Ecology research unit at 黑料视频 Helmholtz Centre for Ocean Research. Her research focuses particularly on restoration measures and the adaptation processes of seagrass to environmental stressors.

Florian Sch眉tte: 鈥濼he ocean absorbs over 90 per cent of the excess heat鈥�.

Since the beginning of industrialisation, mankind has had a massive impact on the Earth's natural heat balance by burning fossil fuels. Since then, the ocean has absorbed more than 90 per cent of the additional heat released. This means that the oceans act as a buffer, without which the earth would already be much warmer today.

However, this extreme warming of the oceans also has many negative consequences: The higher temperatures of the water surface, can lead to increased evaporation - and thus regionally to more precipitation. In tropical regions, the warmer sea surface also favours the development and intensification of tropical cyclones.

In addition, the warming and increased stratification of the upper water layers reduces the mixing of the water. This has an impact on the supply of oxygen and nutrients to living organisms - and therefore on the marine ecosystem. Last but not least, ocean warming contributes to the melting of ice, particularly in the Antarctic and Greenland. This in turn accelerates sea level rise. By the end of the century, an average rise of 50 to 100 centimetres can be expected. Even if we were to stop emitting greenhouse gases now, sea levels would continue to rise for several centuries, as the climate system reacts slowly to such changes.

Florian Sch眉tte is Junior Professor of Physical Oceanography at the 黑料视频 Helmholtz Centre for Ocean Research Kiel. His research interests include the physical observation of oceanic eddies, which can be found throughout the world's oceans.

Morelia Urlaub: "We monitor volcanic slopes under water".

Just like on land, underwater slopes can also begin to slide. However, the scale of submarine landslides often far exceeds those on land. Around one quarter of all tsunamis are triggered by underwater landslides. The causes of such submarine slope failures are still poorly understood, and the dynamic processes on the seafloor remain insufficiently explored. This is mainly because the traces of landslides lie hidden under several hundred or even thousands of meters of water 鈥� and the layer that initially gives way is usually destroyed in the process.

Comprehensive mapping of the seafloor using autonomous underwater vehicles (AUVs) and targeted long-term monitoring aim to close these knowledge gaps. For example, acoustic seafloor positioning networks are being deployed. These consist of several autonomous transponders that communicate with each other. By measuring the travel time of acoustic signals, the distance between the devices can be determined with centimeter accuracy. If the signal travel time changes (for example, due to a slope failure), the relative movements between devices can be calculated.

The goal of this research is to develop an early warning system on the seafloor to collect real-time data on earthquakes, ground movements, and volcanic activity. This would enable reliable monitoring of submarine volcanoes.

Morelia Urlaub is a junior professor of Marine Geomechanics at 黑料视频 Helmholtz Centre for Ocean Research and Kiel University. Her research focuses on submarine natural hazards, particularly those caused by slope instabilities and underwater landslides. She investigates these processes through long-term seafloor observations and numerical modeling.

Amavi Silva: 鈥濼he ocean is our planet's biggest carbon storage鈥�.

The ocean is our ally in the fight against climate change. Since the beginning of industrialization, the ocean has absorbed around a quarter of the carbon dioxide (CO₂) released by human activities. This natural buffering effect has significantly slowed global warming. But CO₂ uptake comes at a high cost: the ocean water is becoming more acidic.

CO₂ enters the ocean at the surface, where it dissolves from the air into the seawater. Whether and how much CO₂ is absorbed depends primarily on the difference in what鈥檚 called the CO₂ partial pressure between the atmosphere and the surface ocean. Put simply, this is the pressure generated by the CO2 dissolved in the surface water and the CO2 in the atmosphere. The natural gas exchange between ocean and atmosphere always works to balance out this pressure difference.

At 黑料视频, researchers are exploring ways to increase the ocean鈥檚 ability to absorb CO₂ in the future 鈥� in order to help meet international climate goals and offset unavoidable emissions. The top priority on the path to climate neutrality is and remains the avoidance of emissions.

Amavi Silva is a marine biogeochemist (postdoc) at 黑料视频 Helmholtz Centre for Ocean Research Kiel. Her research aims to understand the dynamics of the sea surface microlayer 鈥� the ocean鈥檚 鈥榮kin鈥� that controls the air-sea exchange of CO₂.

As the lead scientific partner, the 黑料视频 Helmholtz Centre for Ocean Research Kiel contributes its extensive expertise to the conference. Together with partners from current research projects 鈥� MUNI-RISK, MMinE-SwEEPER, Validity, SAM, BorDEx, MUNIMAP, ErovMUs and REMARCO 鈥� 黑料视频 researchers will present the latest scientific knowledge in talks and in the accompanying exhibition.

Geomar has laid the scientific foundations for munitions recovery

At the opening of KMCW25, 黑料视频 Director Prof. Dr Katja Matthes said:
鈥淔or many years, 黑料视频 has been conducting fundamental research into the clearance of munitions off our coasts. Together with our international project partners, we are increasingly adopting a European approach. As a scientific partner of the conference, we are contributing our expertise in mapping and dealing with leaking hazardous substances. In cooperation with the State of Schleswig-Holstein and the Chamber of Industry and Commerce, we have also established the MUNIMAR Competence Centre, a dedicated platform to advance the development of concrete projects and technologies to deal with legacy munitions鈥�.

Renowned scientists such as Prof. Dr Jens Greinert, Prof. Dr Jacek Beldowski, Prof. Dr Edmund Maser and Hans Sanderson will take part in panels, workshops and the specialist exhibition.

19 June: Public event on sea-dumped munitions
On Thursday, 19 June, all interested parties are invited to the Business Lounge of the Wunderino Arena: From 7:15 p.m. to 9:00 p.m., a discussion will take place under the title 鈥淐ommunicating about sea-dumped munitions: Challenges and opportunities鈥�, addressing how this topic can be communicated transparently and comprehensibly 鈥� beyond fear narratives and with a view to opportunities for a sustainable 鈥淏lue Economy鈥�. The Centre for the Management of Munitions in the Marine Environment Schleswig-Holstein (MUNIMAR) will also be presented. No registration is required.

About: Kiel Munition Clearance Week
In September 2021, experts on the topic of ammunition in the sea met for the first time at the Kiel Munition Clearance Week (KMCW) to exchange ideas and drive forward solutions for ammunition clearance. On the initiative of Jann Wendt (north.io GmbH), the Ammunition Cadastre Sea (AmuCad.org) organised the conference in cooperation with partners from industry and science like 黑料视频. The second KMCW is organised by the Ministry of Energy Transition, Climate Protection, Environment and Nature of the State of Schleswig-Holstein (MEKUN) together with north.io.

鈥淲hat helps the climate is not automatically good for the ocean,鈥� says Prof. Dr Andreas Oschlies, lead author of the study and head of the Biogeochemical Modelling research division at 黑料视频. Together with an international team that is part of the UNESCO Global Ocean Oxygen Network (GO₂NE), he conducted a comprehensive assessment using idealised global model simulations to analyse both the direct impacts of various mCDR approaches on ocean oxygen and their indirect effects through climate mitigation. The results have now been published in Environmental Research Letters.

Ocean fertilisation and seaweed sinking among the most critical approaches

The study identifies several biotic mCDR methods as particularly critical 鈥� including ocean fertilisation, large-scale macroalgae farming followed by sinking of the biomass, and artificial upwelling of nutrient-rich deep water. These approaches involve the enhancement of photosynthetic biomass production, followed by its decomposition in the ocean interior. This remineralisation process consumes oxygen 鈥� at levels comparable to the current rate of global deoxygenation caused by ocean warming.

鈥淢ethods that increase biomass production in the ocean, and subsequently lead to oxygen-consuming decomposition, cannot be considered harmless climate solutions,鈥� says Oschlies. 鈥淥ur model simulations show that such approaches could cause a decrease in dissolved oxygen that is four to 40 times greater than the oxygen gain expected from reduced global warming.鈥�

By contrast, geochemical mCDR approaches that do not involve nutrient input 鈥� such as ocean alkalinity enhancement through the addition of alkaline substances based on limestone 鈥� appear to have minimal effects on ocean oxygen levels and are comparable to simply reducing CO鈧� emissions.

Among all methods examined, only large-scale macroalgae farming with biomass harvesting (i.e. removal from the ocean) resulted in an overall increase in oceanic oxygen levels. In this case, no additional oxygen is consumed within the marine environment, and the removal of nutrients limits oxygen consumption elsewhere. Model results suggest that if deployed at sufficient scale, this approach could even reverse past oxygen losses 鈥� providing up to ten times more oxygen than has been lost due to climate change within a century. However, here it is the removal of nutrients that would negatively impact biological productivity in the ocean.

Call for systematic monitoring of ocean oxygen

Given these findings, the authors advocate for mandatory inclusion of oxygen measurements in all future mCDR research and deployment efforts.

鈥淭he ocean is a complex system which is already heavily under pressure,鈥� says Oschlies. 鈥淚f we intervene with large-scale measures, we must ensure that, no matter how good our intentions are, we are not further threatening marine environmental conditions that marine life depends on.鈥�

Original publication:
Oschlies, A., Slomp, C. P., Altieri, A. H., Gallo, N. D., Gregoire, M., Isensee, K., Levin, L. A., & Wu, J. (2025): Potential impacts of marine carbon dioxide removal on ocean oxygen. Environmental Research Letters.

Background: Carbon dioxide removal as part of climate strategy

Even with ambitious climate policy, Germany is expected to emit 10 to 20 percent of today鈥檚 greenhouse gas levels in three decades鈥� time 鈥� continuing to drive global warming. Carbon dioxide removal (CDR) is therefore being considered to help reach net-zero emissions. The ocean is the key player in the global carbon cycle due to its natural CO₂ uptake and its huge storage capacity. However, these processes typically occur over long timescales. Marine Carbon Dioxide Removal (mCDR) approaches aim to accelerate these natural processes, thereby increasing the ocean鈥檚 carbon uptake capacity.

The scientific advisory board brings together 16 experts covering the fields of marine ecology, dumped munitions, geology, climate, tourism, economics, fisheries, agriculture and social sciences. They represent 黑料视频 Helmholtz Centre for Ocean Research Kiel (黑料视频), Kiel University, the Institute for Terrestrial and Aquatic Wildlife Research (ITAW), the Kiel Institute for the World Economy (IfW), the Institute for Tourism and Spa Research in Northern Europe (NIT), and the German Marine Research Alliance (DAM).

鈥淭his interdisciplinary approach enables us to understand complex ecological, economic and social interconnections and to develop targeted measures that will help us to protect the Baltic Sea more effectively,鈥� the Minister-President said.

鈥淏iodiversity loss, pollution and climate change 鈥� the three global environmental crises are concentrated in the Baltic Sea like under a magnifying glass. With the Action Plan for Baltic Sea Protection 2030, the state government has initiated an effective protection programme. The advisory board will provide an important platform for linking science, administration and politics in support of a vibrant and healthy Baltic Sea. We in Schleswig-Holstein love our Baltic Sea 鈥� and together we will treat it better in future,鈥� said Environment Minister Tobias Goldschmidt.

The members of the advisory board elected Professor Dr Ursula Siebert from the Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover Foundation, as Chair. 鈥淚 am sincerely grateful for the trust placed in me to lead the Scientific Advisory Board for the Baltic Sea Protection Action Plan 2030. This board offers a great opportunity to advise decision-makers and the public at an interdisciplinary scientific level and thus help pave the way for a healthier Baltic Sea,鈥� said Siebert.

Professor Dr Thorsten Reusch of 黑料视频 Helmholtz Centre for Ocean Research Kiel was elected Vice-Chair of the board. 鈥淚 look forward to working with this highly competent interdisciplinary team. This is an important opportunity to contribute our collective expertise as an independent scientific body to political processes. We share the responsibility of preserving the Baltic Sea ecosystem with all its diverse functions 鈥� despite very challenging conditions such as the legacy of heavy overfishing and ocean temperatures rising three times faster than the global average,鈥� Reusch said.

The Scientific Advisory Board will meet at least once a year.

Members of the Scientific Advisory Board for the Action Plan for Baltic Sea Protection:

• Prof. Prof. h. c. Dr Ursula Siebert, University of Veterinary Medicine Hannover Foundation, Institute for Terrestrial and Aquatic Wildlife Research (ITAW B眉sum)
• Prof. Dr Thorsten B. Reusch, 黑料视频 Helmholtz Centre for Ocean Research Kiel, Research Division 3: Marine Ecology
• Prof. Dr Jens Greinert, 黑料视频 Helmholtz Centre for Ocean Research Kiel, Research Division 2: Marine Biogeochemistry
• Dr Thomas Martin, 黑料视频 Helmholtz Centre for Ocean Research Kiel, Research Division 1: Ocean Circulation and Climate Dynamics
• Prof. Dr Christian Winter, Kiel University, Institute of Geosciences
• Prof. Dr Stefan Garthe, Research and Technology Centre West Coast, Kiel University
• Prof. Dr Konrad Ott, Department of Philosophy, Kiel University
• Prof. Dr Nicola Fohrer, Kiel University, Institute for Natural Resource Management, Department of Hydrology and Water Resources Management
• Prof. Dr Marie-Catherine Riekhof, Kiel University, Political Economy of Resource Management with a focus on Marine and Coastal Resources
• Prof. Dr Nele Matz-L眉ck, Kiel University, Executive Director of the Walther Sch眉cking Institute for International Law
• Prof. Dr Torben Tiedemann, Kiel University of Applied Sciences, Faculty of Agricultural Economics
• Prof. Dr Wilfried Rickels, Kiel Institute for the World Economy
• Dr Dirk Schm眉cker, Institute for Tourism and Spa Research in Northern Europe GmbH
• Dr Joachim Harms, German Marine Research Alliance e.V.
• Andreas Burmester, Maritime Coordinator of the Schleswig-Holstein State Government
• Dr Juliane Rumpf, State Commissioner for Nature Conservation, Ministry for Energy Transition, Climate Protection, Environment and Nature of Schleswig-Holstein

About: Action Plan for Baltic Sea Protection 2030

As part of the Action Plan for Baltic Sea Protection 2030 (Aktionsplan Ostseeschutz, APOS), adopted by the state government on 19 March 2024, numerous measures are being implemented to protect the sea. 12.5 per cent of Schleswig-Holstein鈥檚 share of the Baltic Sea is being designated as strictly protected areas. These are intended to serve as refuges and resting zones for animals and plants. To safeguard biodiversity, measures include the restoration of reef structures and seagrass meadows.

To reduce nutrient inputs, the state reached an agreement with the agricultural sector at the end of 2024 to supplement the Fertiliser Ordinance. The aim is to reduce nitrogen and phosphorus runoff from agriculture by ten per cent by 2030 and by a further ten per cent by 2035. This corresponds to a reduction of 400 tonnes of nitrogen and 13 tonnes of phosphorus by 2035 鈥� about six per cent of current loads. In addition, municipal wastewater treatment plant discharge limits are being aligned with state-of-the-art standards, and funding for phosphate precipitation and nitrogen elimination is being continued and expanded.

To address the issue of dumped munitions in the Baltic Sea, the federal government launched an immediate action programme in 2024 and treated the first six tonnes of recovered munitions. In future, offshore platforms will be constructed to carry out the entire process 鈥� from detection to recovery and disposal 鈥� directly at sea.

黑料视频 Side Events:

10 June | 13:00鈥�15:00

Bridging Science, Policy and Society for Sustainable Ocean Management in Africa 鈥� MeerWissen and Future West African Marine Ecosystem (FUTURO)

Organizers:

黑料视频 Helmholtz Centre for Ocean Research Kiel

Federal Ministry for Economic Cooperation and Development (BMZ), Germany

Deutsche Gesellschaft f眉r Internationale Zusammenarbeit (GIZ)

Co-organizer:

Intergovernmental Oceanographic Commission of UNESCO 鈥� Sub-Commission for Africa and the Adjacent Island States (IOC-AFRICA)

Read more:

11 June | 18:00鈥�20:00

No Time to Waste: Tackling Submerged Munitions in European Seas

Organizers:

黑料视频 Helmholtz Centre for Ocean Research Kiel

Helsinki Commission (HELCOM) 鈥� Baltic Marine Environment Protection Commission

Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection (BMUV), Germany

Federal Ministry of Education, Science and Research (BMBF), Germany

Co-organizers:

Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI)

Council of the Baltic Sea States (CBSS)

Institute of Oceanology of the Polish Academy of Sciences (IO PAN)

JPI Oceans 

German Environment Agency (UBA)

Read more: 

Researchers on Site:

Prof Katja Matthes, Director of 黑料视频 (expertise in ocean and climate, CO鈧� storage and removal, and international agreements)

Prof Arne K枚rtzinger (expert in ocean observation and research in the highly relevant upwelling regions off West Africa)

Dr Toste Tanhua (developer of innovative instruments for ocean observation in cooperation with merchant vessels and sailing ships)

Prof Jens Greinert (specialist in the recovery of submerged munitions in the North Sea, Baltic Sea and other European waters)

With a net bag and neoprene: Underwater gardening for nature and climate protection

The method is called single-shoot transplantation and is currently considered the most effective technique for reintroducing seagrass. It requires many hands. This summer, five non-governmental organisations (NGOs) and numerous volunteer divers are taking on seagrass restoration on a larger scale for the first time.

"The pilot phase is over 鈥� now we are moving into the field," says Prof. Dr. Thorsten Reusch, Head of the Marine Ecology research department at 黑料视频. "The fact that the NGOs are now independently restoring seagrass meadows with the help of trained divers is great news for biodiversity in the Baltic Sea鈥檚 coastal areas and for natural climate protection."

Seagrass - the underestimated natural CO鈧� sink

Seagrass is a true all-rounder underwater: it provides important habitats for fish and other creatures, stabilizes sediment, calms waves, and filters pathogens from the water. Most importantly, it binds carbon very effectively and over the long term. This makes seagrass meadows one of the most important natural CO鈧� sinks in our coastal waters.

This is precisely where the ZOBLUC project, which is funded by the Federal Ministry for the Environment and started this year under the leadership of 黑料视频, comes in. ZOBLUC stands for "Zostera marina as a blue carbon sink in the Baltic Sea" and combines research, protection, and restoration of seagrass meadows. The focus is on the extent to which these ecosystems act as natural carbon reservoirs 鈥� and how they can be specifically strengthened. The project is part of the Natural Climate Protection Action Programme (ANK) and is funded by the federal government and the state of Schleswig-Holstein.

鈥淪eagrass meadows are like undersea moors,鈥� explains Reusch. 鈥淭hey store carbon in the oxygen-poor sediment for centuries 鈥� this makes them an underestimated but effective weapon in the fight against climate change.鈥�

But seagrass meadows are under threat. Excessive nutrient inputs and the resulting excessive growth of algae, mechanical disturbances such as anchors, and rising water temperatures have led to the disappearance of seagrass in many places in recent decades. However, according to 黑料视频 data, conditions have improved again on some stretches of coast. 鈥淚n order to jump-start the slow natural colonisation, it makes sense to renaturalise seagrass in carefully selected areas.鈥�

Citizen science for marine conservation

The involvement of citizens in renaturalisation as part of the citizen science approach is a central element of ZOBLUC. The training formats required for this were developed over several years and gradually expanded: in 2023, 黑料视频 researchers developed an eight-part pilot course and offered it in cooperation with Sea Shepherd for a small group of experienced 鈥渃itizen divers.鈥� In the following year, 2024, the training courses were extended to diving instructors and diving club leaders.

2025 now marks the transition to the area: the members of five NGOs 鈥� Sea Shepherd Germany, Mission F枚rde, Lake Divers (Just1Ocean), Seagrass Conservation e.V. (SeaGCon, in formation) and Greenpeace 鈥� will be trained. They will then look after nine scientifically selected areas in the Baltic Sea, from Holnis to Fehmarn, where seagrass has either completely disappeared or is only present in small remnants. Targeted planting is intended to fill these gaps and create a long-term network. The suitable renaturalisation areas and donor species are selected by 黑料视频 and approved in close consultation with the Schleswig-Holstein Ministry of the Environment (MEKUN). The measures are scientifically accompanied by a monitoring programme that documents environmental conditions and planting successes.

Nine areas, five NGOs, one common goal

For Christin Otto from Sea Shepherd, who is coordinating the training courses, this mission is a central concern: 鈥淲e are thus consistently continuing our long-standing commitment to protecting the Baltic Sea 鈥� with direct, effective marine protection. Thanks to the cooperation with 黑料视频, we are able to further expand our conservation efforts and make a sustainable contribution to the preservation of important habitats.鈥� 鈥淲e offer nature conservation that you can take part in,鈥� says biologist and research diver Christian Lieberum. He is the full-time coordinator of the Citizen Science programme. 鈥淭he response has been huge,鈥� he says. Not all those interested could be offered a training course. 鈥淏ut we鈥檙e only just getting started. This success story will hopefully continue for a long time to come.鈥�

Experience the sea 鈥� protect nature

鈥淲e only want to protect what we know and love,鈥� says Dr. Mark Lenz, a marine biologist at 黑料视频 Helmholtz Centre for Ocean Research in Kiel. He initiated the project last year and is delighted that it is continuing this year. 鈥淥nce you have seen with your own eyes how diverse life is just below the surface of the water, you will never look at the Baltic Sea with indifference again. That's exactly the experience we want to offer children and young people through 鈥楽norkeling.City鈥�.

This is made possible by the association Pro Ocean and funding from the BINGO! Environmental Lottery. The BUND-Umwelthaus in Neustadt, BUND SH and the Tourism Agency L眉becker Bucht are providing the snorkeling equipment. Dr Henry G枚hlich, a marine biologist at 黑料视频, is coordinating and managing the project on a voluntary basis. The success of the programme also relies on the support of teams from Ocean Summit, the Heinrich B枚ll Foundation SH, Kiel Marketing, the Arbeiter-Samariter-Bund SH, and freediving instructor Kjell Wassermann.

School classes and students take the plunge

From 2 June to 4 July, school classes will go snorkelling almost every weekday. Each course lasts around three hours. Before entering the water, participants receive an introduction to the unique characteristics of the Baltic Sea and its marine life, followed by a debrief and discussion after the snorkelling session. The groups are guided by students from Kiel University (CAU) and 黑料视频 who have been trained in environmental education, first aid, lifeguarding and snorkelling instruction.

On 12 June, 25 biology students from Kiel University (CAU) will join the 鈥楽norkeling.City鈥� team for a day-long excursion, organised by Dr Kim Wagner and Dr Daniela Winkler. The trip is supported by the CAU Alumni and Friends Association.

Vision for the future: Every child living on the Baltic Sea coast should have the opportunity to explore the underwater world

The organisers have an ambitious goal: every child living along the Baltic Sea coast of Schleswig-Holstein should one day have the opportunity to explore the underwater world of the Baltic Sea. To realise this vision, the project needs additional partners and long-term funding. It鈥檚 a goal worth pursuing 鈥� because both Lenz and G枚hlich are convinced that anyone who has experienced a seagrass meadow up close will understand the vital role that each animal and plant plays in the marine ecosystem, and be motivated to help protect them.

鈥淲e analysed the problems and concluded that they are driven by short-sighted national calls for higher, unsustainable catches, compromising all levels of decision making,鈥� says lead author Dr Rainer Froese, a fisheries scientist at 黑料视频. 鈥淓nvironmental factors such as warming waters and oxygen loss also play a role, but overfishing is so strong that it alone suffices to collapse stocks.鈥� He adds: 鈥淲e propose a new approach to EU fisheries management that would overcome the problems, be doable within existing legislation, and lead to profitable fisheries from healthy fish stocks within a few years.鈥�

The European path to setting annual quotas

The EU鈥檚 Common Fisheries Policy (CFP) is based on the United Nations Convention on the Law of the Sea (UNCLOS), which states that fish populations are to be maintained or restored to levels that can support maximum sustainable catches. In northern Europe, this is implemented through legally binding total allowable catches (TACs), which are advised scientifically by the International Council for the Exploration of the Sea (ICES), an intergovernmental organization with working groups consisting mostly of scientists from national fisheries institutions. Based on this advice, the European Commission proposes annual quotas, which are then discussed with member states and stakeholders. Ultimately, the Council of EU Fisheries Ministers decides on the legally binding total allowable catch for the following year. Unfortunately, this process often results in quotas that were increased at every step 鈥� with harmful consequences for fish stocks.

Mismanagement in the western Baltic Sea

The western Baltic Sea is a window into the dynamics between fish and fisheries 鈥� a relatively simple ecosystem for which extensive data are available, and which is fished solely under EU control.

鈥淭he western Baltic is dominated by three commercially important species: cod, herring and plaice,鈥� explains Prof. Dr Thorsten Reusch, Head of the Marine Ecology Research Division at 黑料视频. 鈥淟ong-standing overfishing of cod and herring has led to the recent collapse of these fisheries, whereas flatfish such as plaice, flounder and dab 鈥� which are less demanded and fished less intensively 鈥� have shown stable or even increasing stock sizes.鈥� In 2022, overall, less than a tenth of what could have been sustainably caught from healthy stocks was actually landed. Reusch continues: 鈥淚t鈥檚 the small-scale coastal fishers who are suffering the most, often without having done anything wrong, except perhaps relying on fishing associations that lobbied for unsustainable quotas.鈥�

Systematic overestimation and phantom recoveries

In order to manage catches sustainably, the International Council for the Exploration of the Sea (ICES) advises on how much fish of a given species of fish can be extracted annually without threatening the long-term viability of the stock.

However, ICES鈥檚 assessments repeatedly overpredicted stock sizes for the upcoming year for which sustainable catches were to be advised. These overly optimistic projections suggested that fish stocks were recovering and could support much higher catches, when, in reality, the stocks were stagnating or declining. 鈥淲e鈥檙e talking about 鈥榩hantom recoveries鈥�,鈥� says Froese, 鈥渞ecoveries that were predicted but never happened.鈥�

The overfishing ratchet: when the system undermines its own goals

Building on the already too high ICES advice, the European Commission often proposed even higher catch limits, which the ministers in the EU Council usually approved, or sometimes increased further. As a result, official quotas permitted the capture of far more fish than the stocks could replenish. In some years even more than there were fish in the water. The authors call this process the 鈥榦verfishing ratchet鈥�: like a mechanical ratchet, it only turns in one direction. This process strongly favours higher catches at every step, leading to total allowable catches (TACs) that often exceed what fishers are able to catch.

As Froese notes: 鈥淚nterestingly, actual catches often remained below these inflated quotas 鈥� simply because fishers stopped fishing when the cost of chasing the last fish exceeded the value of the catch.鈥�

A new independent authority for ecosystem-based catch advice

The Common Fisheries Policy included an explicit deadline of 2020 to end overfishing 鈥� a goal that was clearly missed, as Thorsten Reusch points out. 鈥淓urope must play a leading role by making its own fisheries sustainable if it hopes to encourage other regions of the world to adopt sustainable fishing practices.鈥� His appeal: 鈥淭he EU must take its sustainability goals seriously and implement the CFP according to its stated objectives, urgently.鈥�

To make the process more transparent and ensure accountability, the researchers propose creating a new politically independent institution with a clear mandate to provide robust scientific estimates of the highest sustainable annual catch for every stock, in line with ecosystem-based fisheries management (EBFM) principles. This would enable the EU to finally implement its own laws and effectively end overfishing.

Froese concludes: 鈥淭o be successful, such an institution would need to operate with the same level of independence as a central bank.鈥� He reiterates: 鈥淚mplementing sound scientific advice can lead to highly profitable fisheries from large fish stocks in healthy European seas in many cases, and within a few years.鈥�

Original Publication:

Froese, R., Steiner, N., Papaioannou, E., MacNeil, L., Reusch, T.B.H., Scotti, M. (2025): Systemic failure of European fisheries management, Science.

DOI: 10.1126/science.adv4341

Two Decades of Interdisciplinary Data

The study is based on an exceptionally rich dataset, including results from 34 research expeditions, measurements by autonomous underwater gliders, satellite observations, and data from long-term ocean moorings. The team combined physical, chemical, and biological parameters to uncover relationships between currents, nutrient availability, and species composition.

鈥淥nly by combining all of these different data sources were we able to identify patterns that would have remained invisible using physical data alone,鈥� says first author Dr Florian Sch眉tte, Assistant Professor of Physical Oceanography at 黑料视频. The findings not only offer new insights into the ecosystem, but also lay the groundwork for digital tools such as coupled ecosystem models or even a Digital Twin of the Ocean 鈥� a virtual model that integrates massive interdisciplinary datasets. 鈥淲hat we did here is essentially the core idea of a digital twin: bringing together multiple perspectives to understand the system as a whole,鈥� Sch眉tte explains.

Three Key Processes Bring Nutrients to the Surface

From the extensive dataset, the researchers identified three physical mechanisms that drive the upward transport of nitrate 鈥� the key limiting nutrient for phytoplankton growth in the Atlantic 鈥� from deeper layers to the surface, where it fuels biological productivity:

1. Wind-Driven Island Wakes:
   The first mechanism involves 鈥渋sland wakes鈥� 鈥� swirling wind patterns that form when the steady northeast trade winds are deflected by the high volcanic peaks of Santo Ant茫o and Fogo. These wind distortions create intense local shear zones that, in turn, generate small but highly productive water eddies. These eddies enhance vertical mixing and nutrient transport in the water column.
2. Mesoscale Ocean Eddies:
   The second process involves large-scale ocean eddies 鈥� so-called 鈥渕esoscale eddies鈥� with diameters of up to 120 kilometers. These features regularly form off the West African coast, where they trap cold, nutrient-rich, and fresher water, carrying it westward toward the Cape Verde Islands. When these eddies encounter islands or shallow waters, they release their nutrient-rich cores and enhance local vertical mixing.
3. Internal Tidal Waves:
   The third mechanism results from the interaction of tides with the steep underwater topography of the islands. The Cape Verde Archipelago sits in a deep-sea basin (the Cape Verde Basin) with depths of 3,000 to 4,000 meters. Here, regular tidal flows are disrupted by seamounts and island slopes, generating so-called internal tidal waves. These waves oscillate within ocean layers of differing densities and can travel long distances 鈥� or break when encountering steep slopes or shallows, much like surface waves breaking on a beach. When internal waves break, they release significant energy, dramatically increasing vertical mixing. This effect is especially strong south of Santo Ant茫o, where 黑料视频 recorded the highest mixing rates ever measured 鈥� accompanied by flow speeds several times higher than the original deep-sea tidal current.

The Key Insight: Physics Determines Who Lives Where

鈥淎ll of these processes bring nitrate into the sunlit surface layer, where it stimulates phytoplankton growth 鈥� the foundation of all marine life,鈥� explains Dr Sch眉tte. These productive zones exhibit up to ten times more zooplankton biomass, higher fish catches, and more whale sightings. Even annual catch volumes of mackerel and tuna in the Cape Verde region strongly correlate with the strength of these small-scale physical processes and associated chlorophyll levels.

But the study鈥檚 key finding goes beyond productivity: It shows that not only the quantity of life, but also the type of organisms present, depends on the underlying physical dynamics. Zooplankton communities differ markedly between regions dominated by tidal mixing, wind-driven island wakes, or large ocean eddies 鈥� and these differences appear to propagate up the food chain to fish and marine mammals.

鈥淲here tides dominate, we find different animals than in areas influenced by wind or eddies,鈥� says Sch眉tte. 鈥淲hat used to seem like chaotic variety now shows recognizable patterns. We're beginning to structure the ocean 鈥� and understand how biodiversity emerges.鈥�

Relevance for Marine Conservation and Sustainable Use

For the first time, the study reveals in detail how marine biodiversity around the Cape Verde Islands is shaped by physical ocean processes and underwater topography. This holistic view provides a crucial foundation for understanding the entire ecosystem 鈥� from physical drivers to microscopic algae, fish, and whales.

Such a systemic perspective is especially important for marine conservation and sustainable fisheries management. Until now, many fishery decisions have relied primarily on catch statistics. This study shows that forward-looking ocean monitoring requires more: interdisciplinary data collection that captures physical, chemical, and biological processes 鈥� ideally combined with satellite data and long-term observations on site.

Original Publication:

Sch眉tte, F., Hans, A.C., Schulz, M., Hummels, R., Assokpa, O., Brandt, P., Kiko, R., K枚rtzinger, A., Fiedler, B., Fischer, T., Rodrigues, E., Hoving, H-J., Hauss, H. (2025). Linking physical processes to biological responses: Interdisciplinary observational insights into the enhanced biological productivity of the Cape Verde Archipelago, Progress in Oceanography, 235, 103479.

Contact:
Prof. Hinrich Schulenburg
Spokesperson CRC 1182 鈥濷rigin and Function of Metaorganisms鈥�, Kiel University
Phone: +49 431-880-4141
Email: hschulenburg(at)zoologie.uni-kiel.de
 
Prof. Ute Hentschel Humeida
Research Unit - Marine Symbioses
Research Division 3 - Marine Ecology
黑料视频 Helmholtz Centre for Ocean Research Kiel
Phone +49 431 600-4480
Email: uhentschel(at)geomar.de

鈥淭his expedition has given us a glimpse into one of the most remote and biologically rich parts of our ocean. This is exactly why the Ocean Census exists 鈥� to accelerate our understanding of ocean life before it鈥檚 too late,鈥� said Dr. Michelle Taylor, head of science and expedition principal investigator at the Ocean Census, and senior lecturer at the University of Essex. 鈥淭he 35 days at sea were an exciting rollercoaster of scientific discovery; the implications of which will be felt for many years to come as discoveries filter into management action.鈥�

Mother Nature threw everything she had at the expedition, said Taylor, including a subsea earthquake, tropical storm force winds with hurricane-level gusts, eight-meter (26-foot) waves, and icebergs to navigate.

Located in the South Atlantic, the South Sandwich Islands are part of a rich mosaic of geologic features such as hadal zone trenches, underwater volcanoes, and spreading centers 鈥� features created by tectonic forces that have supported the evolution of species found nowhere else on the planet. It took eight days for the research vessel to travel to the islands from the port of Punta Arenas, Chile.

The GoSouth team, led by Co-Chief Scientist Dr. Jenny Gales, discovered two pockmarks in the mapping data of an underwater caldera 鈥� a bowl-shaped depression in the seafloor, left after a volcano erupts. Pockmarks can indicate hydrothermal activity. Using a 鈥渘ested鈥� approach, the team deployed Schmidt Ocean Institute鈥檚 remotely operated vehicle, SuBastian to map the pockmarks at a higher resolution and confirm the presence of vents.

The larger pockmark contained three hydrothermal vents, and the smaller contained one. Located at 700 meters depth (nearly 2300 feet), they are one of the shallowest hydrothermal vents to have been discovered near the South Sandwich Islands, and the only ones to be explored using a remotely operated vehicle. The tallest vent chimney was four meters (13 feet), making it about as tall as a basketball hoop. Each vent was covered with an array of life dependent on chemosynthesis, including sea snails and barnacles. Thriving coral gardens and large sponges were found in close proximity to the vents 鈥� an unusual observation, said Taylor.

鈥淒iscovering these hydrothermal vents was a magical moment, as they have never been seen here before,鈥� said Gales, an associate professor in Ocean Exploration at the University of Plymouth (UK). 鈥淚t鈥檚 an incredible discovery that provides valuable insights into the area鈥檚 tectonic activity. Making such a discovery is rare. It highlights the importance of ocean exploration and seafloor mapping.鈥�

In addition to the vents, other notable observations during the expedition included:

• In the trench, scientists found snailfish eggs that had been laid on a black coral, as well as a potential new sea cucumber species;
• large pumice blocks, indicating that the South Sandwich Islands are capable of explosive volcanism; 
• a vibrant coral garden located west of Saunders Island at a depth of 120 meters (394 feet); 
• Capturing the first footage of Akarotaxis aff. gouldae, a species of dragonfish that was discovered two years ago.

鈥淭he challenging ocean and weather conditions and the isolated location of the South Sandwich Islands capture the imagination of the boldest explorers 鈥� often the closest humans to the vessel were on the International Space Station,鈥� said Schmidt Ocean Institute鈥檚 Executive Director, Dr. Jyotika Virmani. 鈥淲e are proud to have collaborated with Ocean Census in their mission to advance the discovery of marine life and GoSouth in their quest to better understand the geological nature of this dynamic corner of the world.鈥� 

Contact person:
Dr. Tom Kwasnitschka, tkwasnitschka(at)geomar.de

'Various technical approaches have already been tested, some of which have had a positive effect on lakes,' says Prof Dr Andreas Oschlies, Professor of Marine Biogeochemical Modelling at the 黑料视频 Helmholtz Centre for Ocean Research Kiel. 'However, artificial oxygenation cannot work miracles 鈥� it only temporarily alleviates the symptoms and does not address the underlying causes.'

Together with Prof. Dr Caroline P. Slomp, Professor of Geomicrobiology and Biogeochemistry at Radboud University in the Netherlands, Andreas Oschlies heads the Global Ocean Oxygen Network (GONE). GO₂NE is an international expert committee of the United Nations Intergovernmental Oceanographic Commission (IOC UNESCO) researching the causes and consequences of declining oxygen levels in the ocean. GO₂NE held its first international workshop on artificial oxygenation in autumn 2024. The results of this workshop were published last week in the scientific journal EOS.

Main causes of oxygen loss in coastal seas

Coastal seas naturally obtain oxygen through exchange with the atmosphere and through photosynthesis by phytoplankton on the surface. Deeper water layers can only obtain oxygen through exchange with surface water. Seawater loses oxygen through bacteria consuming it when decomposing organic material. These bacteria can thrive particularly well when the nutrient supply is high, which is why excessive nutrient inputs (especially nitrogen and phosphorus) from wastewater and agriculture are among the main causes of falling oxygen levels. In addition, water bodies are warming, meaning less oxygen can be dissolved in warmer water. Warm layers of water overlying cooler ones also inhibit the mixing of the water layers.

Oschlies: 鈥淭here are now huge zones in the Baltic Sea where there is no oxygen at all. We call these zones anoxic, i.e. oxygen-free. They are colloquially referred to as 'dead zones'. They are not completely devoid of life, as there are bacteria that can still survive in this environment. However, these areas are absolutely hostile to all other organisms.鈥�

Limits and risks of artificial oxygen input

Oschlies and Slomp investigated two technical approaches for supplying oxygen to bodies of water: air or pure oxygen injection (bubble diffusion), and pumping oxygen-rich surface water into deeper layers (artificial downwelling). Both methods have already been tested locally, producing partially positive results. However, as soon as the measures are discontinued, the anoxia usually returns very quickly. Slomp: 鈥淭his artificial introduction of oxygen can be used successfully in lakes, shallow estuaries or small bays. However, the effect only lasts as long as the operation is maintained.鈥� The Chesapeake Bay near Baltimore in the USA is one example of this. After decades of aerating a shallow tributary, the systems were switched off and the oxygen levels fell back to their original levels within a day.

The artificial supply of oxygen also poses ecological risks. For instance, the injection of oxygen can intensify the upward movement of gases such as methane, which is a potent greenhouse gas. Changes in temperature and salinity distributions, as well as underwater noise, could affect marine habitats and, in extreme cases, lead to a further decrease in oxygen levels. 鈥淭hese processes should only be used after thorough testing and accompanied by environmental monitoring,鈥� emphasises Oschlies.

No substitute for climate protection and reducing nutrient inputs

The expansion of plants for the production of green hydrogen is currently a topic of debate. Green hydrogen is produced by electrolysis, which splits water into hydrogen and oxygen. If the electrolysers are located near the sea, the oxygen produced as a by-product could be used for oxygen enrichment measures in coastal marine regions. However, the researchers urge caution, stating that while technical interventions could be beneficial where suitable conditions prevail, they would need to be part of comprehensive water protection strategies.

Slomp鈥榮 conclusion: 鈥淭he technical possibilities for supplying oxygen do not replace the need for consistent climate protection and the reduction of nutrient inputs from agriculture and wastewater. However, under certain conditions, they can help mitigate the worst consequences of oxygen deficiency, at least temporarily.鈥�
 

Original Publication:

Slomp, Caroline P./Oschlies, Andreas (2025): Could bubbling Oxygen revitalize dying coastal seas?. Eos.

Volcanically active laboratory on the seafloor

鈥淭he Brothers volcano is like a laboratory on the seafloor for us. Nowhere else in the Kermadec Arc is there such an active caldera with so many hot springs and hydrothermal vents,鈥� says Dr Christian Berndt, cruise leader and Professor of Marine Geophysics at the 黑料视频 Helmholtz Centre for Ocean Research in Kiel. 鈥淭his combination of a large volcanic crater, ultra-hot fluids, and unique habitats is key to understanding how underwater volcanoes work and how raw materials are formed on the seafloor.鈥�

Following on from the MARUM drilling campaign

This expedition builds directly on a research cruise conducted by the MARUM Centre for Marine Environmental Sciences at the University of Bremen. During this cruise, research was also carried out on the Brothers volcano using the research vessel SONNE. That expedition focused on scientific drilling to study hydrothermal processes and the formation of seafloor metal deposits. This expedition complements those investigations by taking large-scale geophysical measurements, which provide important contextual data for interpreting the drill cores.

German鈥揘ew Zealand partnership

The project is a successful example of international cooperation in marine research. In addition to 黑料视频, the New Zealand research organisation GNS Science (in M膩ori: Te P奴 Ao) is also involved in the expedition. This collaboration on exploring the seabed around the Pacific island state has lasted for over thirty years, combining state-of-the-art technology with decades of local expertise. Recently, the Deputy New Zealand Ambassador to Germany, Evelyne Coulombe, also visited 黑料视频 to find out more about the cooperation.

Knowledge for greater safety and sustainable resource utilisation

The results of the expedition will help us to better understand the history of the Brothers volcano and improve risk assessments for future eruptions and tsunamis in the region. At the same time, the results will provide a valuable foundation for assessing mineral deposits in the deep sea.

Background: Caldera 

A caldera is a large, cauldron-shaped crater formed when large quantities of magma escape underground during a volcanic eruption. The overlying rock loses its supporting function and collapses. Such calderas can be several kilometres in size and hundreds of metres deep - both on land and underwater.
 

The expedition at a glance:

Name: BRASS (Brothers Volcano Seismic Structure)

Expedition leader: Professor Dr Christian Berndt

Period: 03.05.2025 鈥� 29.05.2025

Start and end: Auckland (New Zealand)

The Past as a Key to the Future

Prof Cui鈥檚 research focuses on periods in Earth鈥檚 history greenhouse gases were released in massive quantities over geologically short timescales 鈥� often associated with global warming events and mass extinctions. At 黑料视频, she is particularly interested in the Miocene epoch, which ended about 5.3 million years ago, when global temperatures were approximately two to three degrees Celcius warmer than today.

鈥淥ur hypothesis is that warmer climates lead to oxygen loss in the ocean, because less oxygen can dissolve in warmer water,鈥� says Cui. But oxygen levels are not driven by temperature alone 鈥� ocean circulation also plays a crucial role. And millions of years ago, ocean currents looked very different from today. 鈥淭here was no land bridge between North and South America yet, so the waters of the Atlantic and Pacific could still mix,鈥� Cui explains. All these factors have to be taken into account to answer the central question: how did the loss of oxygen impact marine life?

Into the Depths: A Focus on the North Atlantic

To investigate this, Cui鈥檚 work focuses on the North Atlantic between 50 and 70 degrees north, east of Greenland 鈥� a region known for its nutrient-rich waters. 鈥淭he North Atlantic is not only one of the most productive regions of the ocean, but also a key area for the global carbon and oxygen balance,鈥� says Cui. 鈥淐hanges in these processes can have major impacts on marine ecosystems and the global climate.鈥�

During the international IODP Expedition 395 aboard the JOIDES Resolution drilling vessel, Cui collected deep-sea sediment cores from this region. These cores, essentially a geological diary, contain records of ocean and climate development spanning millions of years and provide valuable insights into past climate extremes. She is now using these data to drive the UVic Earth system model 鈥� a tool that simulates physical, chemical and biological processes in the ocean. The three-dimensional simulations make visible how warmer climates may have altered nutrient cycles and oxygen levels in productive ocean regions such as the North Atlantic.

Fossil Data as a Key to Better Climate Models

鈥淵ing Cui鈥檚 research complements our work perfectly,鈥� says her host, Prof. Dr Andreas Oschlies, head of the Biogeochemical Modelling Research Unit at 黑料视频. 鈥淥ne of the major uncertainties in marine biogeochemical models is their sensitivity to short-term climate fluctuations. By studying past climates, we can understand these processes under very different conditions and improve our models accordingly鈥�. Fossil records, he adds, can help us make more reliable projections of future climate scenarios.

Background: Humboldt Research Fellowship for Experienced Researchers

The Humboldt Research Fellowship supports highly qualified researchers from abroad for a long-term research stay (6 to 18 months) in Germany. Fellows develop and carry out a research project of their own choice in cooperation with a German research institution.

鈥淪ite-specific factors play a crucial role in determining which ocean-based CDR and storage methods could realistically be considered. Our analysis helps us to understand what scale we are talking about when discussing the deployment of these methods in German waters 鈥� and where along the process chains foreseeable bottlenecks or limitations to feasibility might arise,鈥� says co-lead author Dr Wanxuan Yao, who was a climate modeller at 黑料视频 Helmholtz Centre for Ocean Research Kiel at the time of the study.

Comprehensive Assessment of CO鈧� Removal Methods and Their Impacts

For their analysis, the team reviewed current scientific literature and incorporated findings from their own research as part of the CDRmare DAM research mission. For each method, they assessed factors such as the amount of water, materials, energy, land or sea area required, possible by-products and waste streams, necessary infrastructure and transport routes required, operating costs and what is currently known about potential environmental and societal impacts.

鈥淚n addition, we looked at whether there are already established processes for measuring and monitoring CO₂ removal rates and potential environmental impacts for each method. Without such monitoring frameworks, none of the proposed approaches has a realistic chance of ever being deployed on a large scale,鈥� explains co-lead author Dr Teresa Morganti, a marine biologist at the Leibniz Institute for Baltic Sea Research Warnem眉nde at the time of the study.

Ten marine CDR methods shortlisted

At the end of the multi-year selection process, five methods of CO₂ removal remained that could potentially be implemented in German North Sea and Baltic waters. A further five approaches would require deployment in international waters or cooperation with other coastal states.

鈥淭he options we鈥檝e outlined are intended to raise specific, practical questions and challenges that would need to be addressed in the event of any large-scale application, and to provide a basis for further discussion. It鈥檚 important to emphasise, however, that these outlines do not take into account the legal, political or economic frameworks, nor do they address whether the potential environmental impacts of targeted marine carbon removal are consistent with our societal values and ethical principles. These are essential questions that need to be addressed in follow-up studies,鈥� says Dr Nadine Mengis of 黑料视频 Helmholtz Centre for Ocean Research Kiel, co-author of the study and CDRmare co-chair.

Expectations for marine CDR often too high

The research team is therefore working systematically to develop methods and processes that provide a realistic picture of how feasible marine CDR techniques actually are, and what their consequences might be for both people and ecosystems. 鈥淥nce you scale up marine CDR methods for a particular region, making the true scale of interventions tangible, it becomes clear that earlier expectations were often too high because such practical considerations had not been taken into account. We need many more of these context-specific feasibility studies if we are to arrive at robust estimates of the potential for marine CDR,鈥� says Nadine Mengis.

There is also a risk that high expectations might encourage countries like Germany to place too much hope in future technological solutions, while scaling back existing and proven measures to reduce greenhouse gas emissions in the meantime. 鈥淭his must not be the outcome of our research,鈥� stresses Nadine Mengis.

The marine CDR and storage methods described in the study include:

Methods to increase the CO鈧� buffering capacity (alkalinity) of the ocean:

1. Production of a silicate-based alkaline solution and its distribution in shallow coastal waters along Germany鈥檚 North Sea coast

2. Production of a lime-based alkaline solution and its distribution along shipping routes in the German North Sea

3. Spreading of ground basalt of volcanic origin along the German coastline

4. Discharge of sodium hydroxide produced via electrolysis in desalination plants (there are currently no desalination plants in the North Sea or Baltic Sea)

Methods to restore and expand vegetated coastal ecosystems:

5. Establishing and expanding kelp forests around the German North Sea island of Heligoland

6. Restoration and expansion of mangrove forests in Indonesia

7. Artificial upwelling of nutrient-rich deep water to enhance plankton production in the North Atlantic (strengthening the ocean鈥檚 biological carbon pump)

8. Offshore Sargassum (algae) farming in the South Atlantic subtropical gyre, followed by biomass sinking

Methods for storing captured biogenic CO₂:

9. Cultivation of large macroalgae, with subsequent conversion of the biomass into biomethane; the CO₂ released during combustion would be captured and stored in saline aquifers in the German North Sea

10. Direct air capture of CO₂ with subsequent storage in subsea basalt crust off the coast of Norway

Original Publication:

Yao, W., Morganti, T. M., Wu, J., Borchers, M., Ansch眉tz, A., Bednarz, L.-K., et al. (2025). Exploring site-specific carbon dioxide removal options with storage or sequestration in the marine environment 鈥� the 10 Mt CO鈧� yr鈦�鹿 removal challenge for Germany. Earth鈥檚 Future, 13, e2024EF004902.

About: CDRmare

CDRmare is a research mission of the German Marine Research Alliance (DAM). Its full title is 鈥淢arine carbon storage as a pathway to decarbonisation鈥�. The mission started in summer 2021 with six research consortia investigating promising ocean-based CO鈧� removal and storage methods (alkalinisation, restoration of coastal vegetated ecosystems, artificial upwelling, CCS) in terms of their potential, risks and interactions, and integrating these findings into a transdisciplinary assessment framework. In August 2024, CDRmare entered its second three-year funding phase with five research consortia. CDRmare is funded by the German Federal Ministry of Education and Research (BMBF) and the science ministries of the northern German states of Bremen, Hamburg, Mecklenburg-Western Pomerania, Lower Saxony and Schleswig-Holstein.

鈥淔ine-grained, muddy sediments are important reservoirs of organic carbon and pyrite,鈥� says lead author Habeeb Thanveer Kalapurakkal, a PhD student in the Benthic Biogeochemistry working group at 黑料视频. 鈥淲e already knew that sediment resuspension can release significant amounts of CO₂ into the water column. But until now, it was believed that this was mainly due to organic carbon oxidation.鈥� The new study now shows that the major part of the CO₂ release is caused by pyrite oxidation.

Kiel Bight: A Critical Carbon Sink at Risk

The study focused on Kiel Bight, a coastal region in the western Baltic Sea located between the German island of Fehmarn and the Danish islands. This area features a range of sediment types: coarse sandy sediments in shallower waters and fine-grained mud in deeper regions. These muddy sediments are rich in organic matter and play a central role in the carbon cycle of the Baltic Sea. They are affected both by natural forces such as storms and by anthropogenic impacts like bottom trawling.

Laboratory Experiments Reveal New Insights

To study the effects of sediment resuspension, the researchers conducted sediment slurry incubations. They collected sediment samples from different sites in Kiel Bight 鈥� ranging from coarse sandy to fine grained muddy sediments 鈥� and stirred them in laboratory containers filled with seawater. The experiments simulated both oxygen-rich and oxygen-poor conditions. During the incubation period, the team monitored changes in key chemical parameters, including CO鈧� concentrations, pH, sulfate, nutrients and isotope concentrations. These measurements allowed them to identify the underlying processes and assess their impact on the local carbon cycle. The laboratory data were then integrated into a biogeochemical model to better understand the effects of sediment resuspension and oxygen availability.

Pyrite Oxidation: A Key Factor in CO₂ Release

The results show that sediment resuspension leads to substantially greater CO鈧� emissions than previously thought 鈥� mainly due to the oxidation of pyrite. When this iron-containing mineral, typically found in oxygen-poor, muddy seafloor sediments, is disturbed it reacts with oxygen in the water. This reaction generates acid that converts climate-neutral bicarbonate into the greenhouse gas CO₂. A large fraction of the CO₂ generated by pyrite oxidation is subsequently released into the atmosphere. Modeling results suggest that these processes could significantly reduce the region鈥檚 CO₂ uptake capacity. In other words, resuspension can turn the seafloor temporarily from a carbon sink into a carbon source.

Protecting Sensitive Seafloor Areas to Preserve CO₂ Uptake

鈥淜iel Bight, like other parts of the Baltic Sea, acts as an important sink for atmospheric CO鈧�,鈥� says Kalapurakkal. 鈥淥ur experiments and model simulations show that activities such as bottom trawling significantly reduce this capacity by promoting pyrite oxidation and acidification.鈥� The findings underscore the need to protect seafloor areas with fine-grained, muddy sediments 鈥� regions typically rich in pyrite. Kalapurakkal: 鈥淭hese areas need to be protected to maintain the CO₂ uptake capacity of the Baltic Sea.鈥�

Original Publication:

Kalapurakkal, H.T., Dale, A.W., Schmidt, M. et al. (2025): Sediment resuspension in muddy sediments enhances pyrite oxidation and carbon dioxide emissions in Kiel Bight. Commun Earth Environ 6(1), 156.

One such solution, falling under the category of Nature-based Solutions and Ecosystem Restoration, is presented in the study by Prof. Robert Arlinghaus and his team: revitalising lakes by creating shallow water zones and adding deadwood structures. Worldwide, millions of fish are stocked into waters every year to support natural fish populations. The Science study reveals that this practice, known as fish stocking, is not always successful 鈥� and shows how it can be done better. A particular strength of this research lies in its close link between science and application, conducting repeated, whole-lake experiments in collaboration with angling associations.

Habitat improvements work better than fish stocking

In a unique before-after control-impact experiment, the research team compared, over six years and across 20 gravel pit lakes, how fish stocking and habitat enhancement influenced fish populations.

鈥濼his was a unique outdoor experiment where, in close partnership with numerous angling clubs, we tested different management approaches at whole-ecosystem level. There has never been such a large, replicated, and controlled whole-lake experiment of this kind before. I am delighted that our work has now been recognised with the National Frontiers Planet Prize,鈥� said Professor Robert Arlinghaus, project initiator and coordinator.

鈥濷ver six years, around 160,000 fish as well as many other plant and animal species were surveyed before and after the measures, to analyse how different organism groups responded to habitat creation or the release of a total of 40,000 individually marked fish,鈥� added Prof. Johannes Radinger, lead author of the study, former member of Prof. Arlinghaus鈥� research group, and now Professor at Magdeburg-Stendal University of Applied Sciences.

Dr Christopher Monk, now Head of the Marine Behavioural Ecology Group at 黑料视频 Helmholtz Centre for Ocean Research Kiel, played a key role in analysing the extensive field data during his postdoctoral time at IGB, and also contributed to editing the manuscript.

鈥淭he study demonstrated that ecosystem-based management 鈥� particularly through the creation of shallow water zones 鈥� sustainably increased fish populations and reproductive success, while also supporting other organism groups such as dragonflies and aquatic plants,鈥� explained Dr Sven Matern, co-lead author of the award-winning study and former doctoral researcher under Prof. Arlinghaus. In contrast, the widely practised method of fish stocking, still common among many angling clubs and conservation actors globally, proved unsuccessful in this experiment. Adding deadwood structures showed positive, but species- and site-specific effects, and was generally less effective than creating shallow water areas.

Angling clubs as key partners

The BAGGERSEE research and implementation project on which the Science paper was based was funded by the German Federal Ministry of Education and Research (BMBF), the German Federal Ministry for the Environment (BMUV), and the German Federal Agency for Nature Conservation (BfN) from 2016 to 2022. It has been carried out in close cooperation with dozens of angling clubs in the Anglerverband Niedersachsen e.V. (AVN). Hundreds of anglers have been actively involved in implementing management measures and collecting data. Fisheries biologists from the AVN planned and co-ordinated the habitat enhancement work.

"These results have direct implications for how angling clubs manage their waters. A follow-up knowledge transfer project is currently underway to share these findings with angling organisations across Germany, beyond the project region of Lower Saxony,鈥� said Prof. Thomas Klefoth from Bremen University of Applied Sciences, who co-initiated and formerly coordinated the BAGGERSEE project as a fisheries biologist at AVN.

Freshwater fish under threat

Freshwater fish are among the most threatened vertebrate groups worldwide. In Germany, for example, half of all freshwater fish species are considered endangered according to the national Red List. One of the main reasons is the loss of suitable habitats. Declines in fish populations have far-reaching consequences for aquatic ecosystems as well as for commercial and recreational fisheries. Effective conservation and restoration measures are urgently needed to halt and reverse these declines.

"One promising strategy is ecosystem-based management, which aims to improve or restore key ecological processes, habitats and species interactions, rather than focusing solely on eliminating individual stressors or stocking fish,鈥� explained Robert Arlinghaus. However, this comprehensive approach is often costly and administratively complex.

Ecosystem-based management is worth it

Policymakers are therefore often hesitant to invest in ecosystem-based management without solid scientific evidence of its effectiveness. 鈥淲ith our large experimental field study, which included control lakes and thus delivered robust results, we have now provided a scientific foundation for the success of ecosystem-oriented measures. Crucially, ecosystem improvements need to target the most limiting habitats. In gravel pit lakes, that鈥檚 shallow water zones 鈥� though in other water types, restoring floodplains or other key habitats may be more important,鈥� Arlinghaus explained.

National Champions with a chance for major funding

The National Champions for scientific breakthroughs in sustainability were selected by a jury of 100 leading sustainability researchers worldwide, chaired by Professor Johan Rockstr枚m of the Potsdam Institute for Climate Impact Research (PIK). The National Champions now advance to the final round of the competition, in which three International Champions will be named in June 2025. Each will receive one million US dollars to further their research and expand its global impact.

Original publication:

Radinger, J., Matern, S., Klefoth, T., Wolter, C., Feldhege, F., Monk, C.T., Arlinghaus, R. (2023). Ecosystem-based management outperforms species-focused stocking for enhancing fish populations. Science, 379, 6635, 946-951.

Background: Frontiers Planet Prize

The Frontiers Planet Prize is an international science award presented annually by the Frontiers Research Foundation since 2022. It honours researchers whose pioneering work has the potential to mitigate the global environmental crisis and help stabilise Earth鈥檚 ecosystem.

Each year, one National Champion is selected in every participating country. From these, an independent jury of 100 experts selects three International Champions. Each of these outstanding researchers or research groups receives one million US dollars to advance their work and expand its global influence.

The prize aims to unite global efforts in the fight against the environmental and climate crisis 鈥� much like the worldwide mobilisation of resources and expertise seen during the COVID-19 pandemic.

High-Level Visit to the M209 Expedition

President J贸se Maria Neves, internationally recognised as a committed advocate for ocean protection and patron of the UNESCO-initiated Ocean Decade Alliance since 2023, took the opportunity for a hands-on visit. He wanted to be present when the ROV KIEL 6000 underwater robot went on a dive to explore the biodiversity on the doorstep of his own home, to interact with the master and the crew, and to hear first-hand from the international research team about the challenges and opportunities of marine research in Cabo Verde.  

鈥淭he deep-sea research being carried out here with the R/V METEOR is discovering marine biodiversity, revealing the wealth of Cape Verde鈥�, said president Neves. 鈥淲e saw the ROV descend to the ocean floor 鈥� the researchers are conducting dives, mapping our seabed, and identifying different existing species. This is, in every way, a tremendous contribution to science and to Cape Verde鈥檚 future development.鈥� 

Neves also took the opportunity to find out about the work of the three Cabo Verdean marine scientists taking part in the expedition: Rui Freitas from the Atlantic Technical University (UTA) in Cabo Verde, Keider Neves from the Mindelo-based NGO Biosfera 1, and Vanessa Lopes from Projecto Vit贸 on Fogo Island.

鈥淭his is the second and most advanced deep-sea biology survey I鈥檝e taken part in鈥�, says Rui Freitas. 鈥淭o work with the fantastic scientific team led by Henk-Jan Hoving from 黑料视频 is a great experience. By combining our knowledge of coastal and reef fish with the incredible biodiversity of deep-sea ecosystems, we are strengthening Cabo Verde鈥檚 role as a hotspot for marine biodiversity. The METEOR鈥檚 advanced underwater observation technologies have made an important contribution to deep-sea research in Cabo Verde and opened up exciting new opportunities.鈥�

Crustacean expert and taxonomist Keider Neves adds: 鈥淎s a Cabo Verdean scientist interested in the country鈥檚 rich marine biodiversity, this is a unique opportunity to explore first hand the mesophotic to deep-sea ecosystems off Cabo Verde and collect samples of species that are little known or new not only to the country but also to science.鈥�

Vanessa Lopes adds: 鈥淭he presidential visit was a valuable opportunity to share some of our findings from the M209 Basis expedition. We鈥檝e encountered both pristine marine environments and areas impacted by pollution, highlighting the urgent need for improved management. There is significant work ahead, and collaboration among all stakeholders will be essential to ensure effective, ecosystem-based marine management in Cabo Verde鈥�.

M209: Exploring the Deep-Sea Biology of Cabo Verde

The M209 expedition, entitled 鈥淏ASIS鈥�, is dedicated to exploring deep-sea habitats around the Cabo Verde Islands. It ties in with POSEIDON cruise POS532 in 2019 and a number of other field campaigns. The focus is on biodiversity and food webs across various deep-sea zones, from the mid-water column to the seafloor. Using high-tech tools such as towed cameras, acoustic sensors, and environmental DNA samples, the researchers aim to document the fragile and largely unexplored habitats off Cabo Verde. These data are not only of great scientific value but also provide crucial foundations for local authorities, universities and NGOs for the designation of future implementation of marine protected areas within Cabo Verde鈥檚 territorial waters.

Strengthening the Scientific Partnership Between Cabo Verde and 黑料视频

The visit of the Head of State is a special honour for German marine research 鈥� it is the highest ranking visit to a German research vessel in the region so far. President Neves has been a reliable partner in the scientific cooperation between Cabo Verde and 黑料视频 from the very beginning. In addition to joint research projects, this cooperation includes the operation of the Ocean Science Centre Mindelo (OSCM), which acts as a hub for ocean research and knowledge exchange in West Africa. He laid the foundation stone for the OSCM in 2014 with the scientific director Prof. Arne K枚rtzinger from 黑料视频. In cooperation with the Atlantic Technical University (UTA) and the Kiel University (CAU), the OSCM strengthens regional scientific capacities through various academic programmes, such as the WASCAL master鈥檚 programme.

In autumn 2023, the presidents of both countries, H.E. Jos茅 Maria Neves and Federal President Frank-Walter Steinmeier, met at OSCM and expressed their appreciation for each other and their interest in continuing along this path together. The fact that the President of Cabo Verde took the time to personally experience the expedition highlights the importance of these joint efforts to protect and understand the ocean.

The research, published today in Nature Communications and led by the University of Bristol, provides the clearest ever picture of how the underlying transport system, 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.

The Pathways of Arctic Substances: The Transpolar Drift

The Transpolar Drift carries sea ice, fresh water, and 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, such as nutrients, gases, organic compounds, and human-made pollutants 鈥� including microplastics and heavy metals 鈥� from 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.

As the Arctic Ocean is a highly changeable environment, rather than following a steady course, river-sourced matter takes diverse, seasonally shifting routes shaped by changing shelf conditions and ocean currents, along with the formation, drift, and melting of sea ice. This results in rapid and widespread redistribution of both natural and pollutant matter.

Seasonal Variability and the Role of Sea Ice

Lead author Dr Georgi Laukert, Marie Curie Postdoctoral Fellow in Chemical Oceanography at the University of Bristol, UK and Woods Hole Oceanographic Institution in Massachusetts, US, said: 鈥淲e found pronounced changes in the composition of Siberian river water along the Transpolar Drift, demonstrating this highly dynamic interplay. Seasonal shifts in river discharge and dynamic circulation on the Siberian shelf drive ocean surface variability, while interactions between sea ice and the ocean further increase the redistribution of river-borne matter.

鈥淎nother key discovery is the increasingly central role of sea ice formed along the Transpolar Drift 鈥� not only as a passive transport medium, but as an active agent in shaping dispersal patterns. This sea ice captures material from multiple river sources during growth, unlike most coastal sea ice, creating complex mixtures that are transported across vast distances.鈥�

Geochemical Tracing and the Year-Long Study

To decode these complex pathways, the international research team analysed seawater, sea ice, and snow samples using oxygen and neodymium isotopes, along with measurements of rare earth elements to produce geochemical tracer data. This geochemical fingerprinting allowed the researchers to track the origins of river-sourced matter and follow how it evolved along its route through the central Arctic over a year-long period.

New Insights from the Largest-Ever Arctic Expedition

The study draws on samples from MOSAiC, the largest-ever Arctic expedition and among the most ambitious polar research efforts, involving seven ice breakers and more than 600 global scientists.

Co-author Dr Dorothea Bauch, Researcher at Kiel University in Germany, said: 鈥淭he findings represent unprecedented year-round observations. Previously, we only had summer data because it was too slow and hard to break through the ice in the winter. This sustained, interdisciplinary Arctic evidence offers important and comprehensive insights, which help us better understand highly complex ocean systems and the possible future implications.鈥�

As summer sea ice continues to retreat due to warmer temperatures, circulation and drift patterns are changing.

Co-author Professor Benjamin Rabe, Research Scientist from the Alfred Wegener Institute and Honorary Professor at the University of Applied Science, in Bremerhaven, Germany said: 鈥淭hese shifts could significantly alter how fresh water and river-derived matter spread through the Arctic, with far-reaching implications for ecosystems, biogeochemical cycles, and ocean dynamics.鈥�

Transpolar Drift Not as Stable as Previously Thought

The research also challenges a long-standing perception of the Transpolar Drift as a stable conveyor of river water. First observed during Norwegian explorer Fridtjof Nansen鈥檚 historic Fram expedition in the 1890s, these latest findings discovered more than 130 years later indicate the Transpolar Drift is highly variable in both space and time.

Dr Laukert added: 鈥淲hile the study does not focus on individual compounds, it illuminates the underlying transport mechanisms鈥攁 critical step for predicting how Arctic matter transport will evolve in a warming climate. If even this iconic current is so dynamic, then the entire Arctic Ocean may be more variable and vulnerable than we thought.鈥�

Original Publication:

Laukert, G., Bauch, D., Rabe, B., Krumpen, T., Damm, E., Kienast, M. Hathorne, E., Vredenborg, M., Tippenhauer, S., Andersen, N., Meyer, H., Mellat, M., D鈥橝ngelo, A., Simoes Pereira, P., Nomura, D., Horner, T.J., Hendry, K., Kienast, S. (2025). Dynamic ice鈥搊cean pathways along the Transpolar Drift amplify the dispersal of Siberian matter. Nature Communications, 24, 28391.

The working group of eleven researchers has now presented its findings and ten key recommendations on the deep sea and ocean health. Under the leadership of Prof. Dr Sylvia Sander, Professor of Marine Mineral Resources at 黑料视频 Helmholtz Centre for Ocean Research Kiel, and Dr Christian Tamburini from the French Mediterranean Institute of Oceanography (MIO), the team produced the report, which is being launched today by the EMB in a webinar. The document emphasises, among other points, the urgent need for major investment in deep-sea research to close knowledge gaps and provide a sound scientific basis for decisions such as those concerning deep-sea mining.

鈥淭he ocean is an interconnected system stretching from the coast to the deepest depths,鈥� says Sylvia Sander. 鈥淥f course, the deep sea cannot be considered in isolation from the photic zone or the seafloor.鈥� Therefore, deep-sea research, use and conservation are intrinsically linked to overall ocean health.

Ten recommendations for sustainable deep-sea protection and better collaboration:

The group presents ten central measures for the sustainable protection of the deep sea:

1. Effectively govern human activities in the deep sea
2. Establish an international scientific committee for deep-sea sustainability and protection
3. Contribute to develop and implement deep-sea Environmental Impact Assessment methodologies
4. Support transdisciplinary research programs to better understand the role of the deep sea in Ocean (and human) health
5. Invest in long-term monitoring in the deep sea
6. Launch large-scale and long-term multidisciplinary natural sciences projects to increase knowledge of global deep-sea processes
7. Support research efforts in specific critical research fields
8. Enhance educational, training and research opportunities for all current and future scientists addressing their unique regional challenges
9. Foster the transfer of marine technology and develop training programs
10. Continue to promote the Findability, Accessibility, Interoperability, and Reusability (FAIR) Data Principles

The deep sea: Indispensable ecosystems for life on Earth

Until the late 19th century, the idea that life could exist in the cold, dark, high-pressure depths of the ocean was met with scepticism. It was only with the onset of deep-sea research that the first living organisms were discovered there. Today, scientists know that the deep sea hosts a remarkable diversity of life forms. Complex ecosystems can be found along continental slopes, on abyssal plains or around hydrothermal vents 鈥� so-called black smokers 鈥� many of which remain poorly understood.

Knowledge gaps: Much remains unexplored

It is estimated that around 90 percent of all organisms in the deep sea are still undescribed, and their roles within ecosystems remain largely unknown. Physical oceanography also faces considerable gaps 鈥� for example, in the modelling of deep currents that are crucial for the transport of nutrients and pollutants. In marine geochemistry, little is known about how biogeochemical cycles in the deep sea are affected by human activities such as mining. For instance, scientists still lack a clear understanding of how sediment plumes from the extraction of manganese nodules spread and what long-term impacts they may have on seabed communities. Technical challenges also remain: many modern sensors and monitoring systems are not yet adequately developed for extreme depths, making it difficult to gather essential data. Closing these knowledge gaps is urgently needed to support science-based decision-making for deep-sea governance, the scientists argue.

The challenge: Threats to the deep sea from human activities

What we do know for certain is that the ocean 鈥� of which the deep sea makes up the largest part 鈥� stores vast amounts of CO鈧� and heat, helping to mitigate climate change. It plays a central role in the global carbon cycle and produces more than 50 percent of the planet鈥檚 oxygen. Disruption of these functions could have serious global consequences. Preserving these ecosystem services requires strong protective measures and sustainable use strategies.
Human activities are already affecting the deep sea in many ways. Irreversible changes on human timescales 鈥� such as warming, acidification, and oxygen loss 鈥� are threatening these sensitive habitats. At the same time, overexploitation of fish stocks and non-renewable resources such as oil, gas, and minerals is jeopardising biodiversity and ecosystem functions.

Urgent action needed for ocean health

The scientists agree that 2025 is a decisive year to take action for ocean health. It is crucial to take effective measures against climate change now in order to achieve net-zero emissions by 2050. Sylvia Sander explains:
鈥淐limate change is one of the most alarming threats to our life-support systems and to life on Earth itself. Combined with biodiversity loss, it could soon lead to severe and irreversible disruptions to the entire ocean 鈥� including the deep sea and ice-covered parts of the planet.鈥�

The role of the EU: How Europe can lead the way in protecting the deep sea

The working group emphasises that Europe should take a leading role in the international protection and sustainable governance of the deep sea, particularly through existing international agreements.
鈥淭he EU could play an important role in strengthening international efforts to regulate deep-sea activities,鈥� says Sylvia Sander. 鈥淭his would require the establishment of scientific committees for deep-sea protection and the development of standardised environmental impact assessments.鈥�

The researchers also call for secured funding of transdisciplinary research and long-term monitoring. Sylvia Sander: 鈥淲e need to better understand the state of the ocean to protect and use the deep sea sustainably 鈥� where are changes becoming visible?鈥� More research and technology are essential. 鈥淲e also need to support underrepresented nations in deep-sea research and recognise science as a human right. Only then can we safeguard the health of the ocean 鈥� and the planet 鈥� for future generations.鈥�

Publication: 

Sander, S. G., Tamburini, C., Gollner, S., Guilloux, B., Pape, E., Hoving, H. J., Leroux, R., Rovere, M., Semedo, M., Danovaro, R., Narayanaswamy, B. E. (2025) Deep Sea Research and Management Needs. Mu帽iz Piniella, A., Kellett, P., Alexander, B., Rodriguez Perez, A., Bayo Ruiz, F., Teodosio, M. C., Heymans, J. J. [Eds.] Future Science Brief N掳. 12 of the European Marine Board, Ostend, Belgium.

Background: European Marine Board

The European Marine Board (EMB) is a partnership of 38 organisations from 19 European countries that are active in marine research. Founded in 1995, its mission is to strengthen cooperation in European marine science and develop joint research strategies. The EMB acts as a bridge between science and policy, supports knowledge exchange, and provides recommendations to national authorities and the European Commission to advance marine research in Europe. Its members include leading oceanographic institutes, research funders, and universities with a marine focus.

鈥淎nswering whether and how a CO₂ removal option should be implemented should take its effectiveness, economic viability and its impact on people and the environment into account. However, existing assessment frameworks do not allow doing so. Our framework solves this problem by offering a structured guide for evaluating marine CO₂ removal projects. Stakeholders can use it to analyse all the key issues and make evidence-based decisions,' says Prof. Dr Christian Baatz, a climate and environmental ethicist at the Kiel University (CAU) and co-author of both new articles.

29 criteria for a comprehensive assessment of marine CO2 removal methods

The new framework includes 29 criteria that help to analyse seven key issues. These include questions about the technical, legal and political feasibility of the methods to be assessed, as well as questions about economic efficiency, equity and environmental ethics. Due to this complexity, the researchers recommend that experts from academia, industry, public administration, interest groups and affected populations be involved in the evaluation process.  In line with this principle, the researchers tested the practical suitability of the new evaluation guidelines in a series of transdisciplinary workshops attended by numerous representatives from public administration and interest groups.

鈥淥ur experience in testing the assessment framework shows that no one should attempt to assess a marine CO₂ removal method or a specific project on their own. Due to the high complexity of the issue, an assessment requires the expertise of many people,鈥� says co-author Dr Lukas Tank, also a climate and environmental ethicist at Kiel University.

Ideally feasible and desirable

In addition to the list of criteria, the researchers defined five guiding principles to help ensure that the best possible information is collected during the evaluation process. These guiding principles aim to ensure that the evaluation process is transparent and involves all potentially affected parties.

鈥淯ltimately, it is up to political and societal decision-makers to decide whether a particular marine CO₂ removal project should go ahead. At best, they will choose options that are effective, technically, legally and politically feasible, as well as economically, equitably and environmentally sound. Our assessment framework can help them do this鈥�, says Prof. Dr Gregor Rehder, a chemist at the Leibniz Institute for Baltic Sea Research Warnem眉nde (IOW). He was also an author on both papers and led the CDRmare research network ASMASYS, under which the research for both papers took place.

Original Publications:

Tank, Lukas; Lieske Voget-Kleschin, Matthias Garschagen, Miranda Boettcher, Nadine Mengis, Antonia Holland-Cunz, Gregor Rehder & Christian Baatz (2025): Distinguish Between Feasibility and Desirability When Assessing Climate Response Options. NPJ Climate Action, DOI: 10.1038/s44168-025-00237-2

Christian Baatz, Lukas Tank, Lena-Katharina Bednarz, Miranda Boettcher, Teresa Maria Morganti, Lieske Voget- Kleschin, Tony Cabus, Erik van Doorn, Tabea Dorndorf, Felix Havermann, Wanda Holzh眉ter, David Peter Keller, Matthias Kreuzburg, Nele Matz-L眉ck, Nadine Mengis, Christine Merk, Yiannis Moustakis, Julia Pongratz, Hendrikje Wehnert, Wanxuan Yao and Gregor Rehder (2025): A holistic assessment framework for marine carbon dioxide removal options. Environmental Research Letters, DOI: 10.1088/1748-9326/adc93f

About: CDRmare

CDRmare is a research mission of the German Marine Research Alliance (DAM). The mission started in summer 2021 with six research consortia investigating promising methods for marine CO2 removal and storage (alkalinisation, expansion of vegetation-rich coastal ecosystems, artificial upwelling, CCS) with regard to their potential, risks and interactions, and bringing them together in a transdisciplinary assessment framework.

In August 2024, CDRmare entered its second three-year funding phase with five research consortia. CDRmare is funded by the German Federal Ministry of Education and Research (BMBF) and the science ministries of the northern German states of Bremen, Hamburg, Mecklenburg-Western Pomerania, Lower Saxony and Schleswig-Holstein.

In addition, Germany's national legal framework must be updated to permit offshore CO鈧� storage in the German North Sea seaward of coastal areas. Plans for such reforms are currently under discussion as part of coalition negotiations in Germany.

A Comprehensive Overview of Offshore CO鈧� Storage

A total of 36 experts from eight research and partner institutions contributed to the new interim report. Their goal was to present the research methods and results from 2021 to 2024 in a way that is accessible to policymakers, professionals, and the interested public.

鈥淪toring CO鈧� beneath the North Sea is a controversial topic in Germany. This makes it all the more important for us as a research association to communicate our results in a transparent and comprehensible way. For this reason, we have written this report in German and summarized all the core results in an easily understandable form in the introduction,鈥� says Klaus Wallmann.

Assessing Storage Capacities, Associated Risks, Use Conflicts, and Possible Solutions

The report comprises 15 chapters covering a wide range of topics related to geological CO鈧� storage: from static and dynamic storage capacities and potential risks to marine ecosystems and offshore infrastructure, to newly developed monitoring systems, projected costs of selected storage scenarios, necessary legislative changes, and anticipated conflicts that need to be solved if CO鈧� is to be stored under the already intensively used North Sea.

The full report, written in German, is available for free download at:

Background:

CDRmare is a research mission of the German Marine Research Alliance (DAM). Its full title is 鈥淢arine Carbon Sinks as a Pathway to Decarbonisation.鈥� Launched in summer 2021, the mission originally brought together six research consortia to explore promising approaches for marine CO鈧� removal and storage鈥攕uch as ocean alkalinisation, the restoration of vegetated coastal ecosystems, artificial upwelling, and offshore CCS. These methods are being evaluated for their potential, risks, and interactions within a transdisciplinary assessment framework. In August 2024, CDRmare entered its second three-year funding phase with five research consortia. It is funded by the German Federal Ministry of Education and Research (BMBF) and the science ministries of the northern federal states: Bremen, Hamburg, Mecklenburg-Western Pomerania, Lower Saxony, and Schleswig-Holstein.

Publication:

Wallmann, K. und das GEOSTOR-Konsortium: CO2-Speicherung unter der deutschen Nordsee? Ergebnisse aus drei Jahren Forschung, pp. 1-142, DOI 10.3289/CDRmare.49

Contact:

Sina L枚schke, Pressereferentin CDRmare, Tel: 02353 70 71 527; media@cdrmare.de

Beyond her scientific work, Alexandra has a creative streak. She plays the French horn in an orchestra and enjoys drawing. This talent even supports her research 鈥� she creates illustrations of copepods, the tiny crustaceans she studies, for which there are no high-quality visual representations. Her drawings not only look impressive but also leave a lasting impression on her audience during presentations. 

What is the focus of your research, and how do you approach it? 

Alex: I study copepods in the Baltic Sea. These are tiny crustaceans, and I am studying how they adapt to different environmental conditions, such as different salinities. I鈥檝e taken part in several expeditions aboard ALKOR and a Finnish research vessel to collect copepods. My aim is to cover as much of the Baltic Sea as possible to include the whole salinity gradient up to the coast of Finland. I then keep the copepods in culture rooms for my experiments.

Next, I extract DNA and RNA in the molecular lab. I work with transcriptomics, which involves analysing all RNA molecules expressed at a given time. RNA is essentially the transcription of DNA, and by studying it, I can identify which genes are activated under specific stress conditions 鈥� in my case, low salinity. In the final phase of my PhD, I will also examine how the genomes of copepod populations differ across various locations.

What motivates you? 

Alex: I want to understand how copepods adapt to extreme environmental conditions, as the Baltic Sea is a challenging habitat for a marine species due to its low salinity, which decreases further east. I also want to investigate how climate change might affect them. Some projections predict that the salinity of the Baltic Sea will continue to decrease, and I want to understand if this will impact these little copepods. This question is crucial because copepods form a significant part of the Baltic Sea鈥檚 zooplankton and are therefore a fundamental link in the food chain.

How did you come to focus on copepods as your research subject? 

Alex: I鈥檝e always been interested in environmental changes and climate change and how it affects organisms. However, copepods weren鈥檛 my initial focus. My interest began when I got a job as a student assistant at 黑料视频, where I sorted copepods by species. I analysed long-term zooplankton samples from the Kiel Fjord 鈥� samples were collected every two weeks, and I identified species and tracked their abundance. This made me something of a 鈥榗opepod person鈥�. Then, a junior professor, Reid Brennan, who was also working on copepods, joined the institute, and someone suggested I ask him about a Master鈥檚 project 鈥� so I did!

For the past two years, you鈥檝e been a Young Ambassador for the European Marine Board (EMB). What motivated you to take on this role? 

Alex: I applied because I鈥檓 interested in the interface between science and policy. Every year, the EMB selects two early-career researchers (ECRs) from its member organisations to act as Young Ambassadors and strengthen the links between ECRs and the EMB. When I saw the 黑料视频 call for applications, I applied on a whim 鈥� and I was selected.

What were your tasks as a Young Ambassador? 

Alex: One of our main tasks was to set up a network for ECRs within the EMB, called the EMB ECOP Network. We regularly shared updates on EMB activities, launched a social media series to highlight researchers in our network, and organised monthly webinars on science policy. A particular highlight was organising a workshop on the science-policy interface 鈥� a huge task involving travel logistics, planning talks, and preparing content. This culminated in a conference where we presented the results in a keynote speech to 250 participants.

What have you taken away from your time with the EMB? 

Alex: I learned that there are many ways to get involved, but that time and support are often the biggest challenges. For ECRs, it鈥檚 not always easy to balance research with activities like science communication or policy work. One solution could be to incorporate these activities into research funding proposals, so that they鈥檙e part of the scientific career from the start. Overall, it was a fantastic experience that I would do again in a heartbeat. The EMB secretariat was incredibly supportive, and I would highly recommend this to anyone interested in science policy.

In February, we celebrated the International Day of Women and Girls in Science. What do you think about having a specific day for women and girls in science? 

Alex: Ideally, it wouldn鈥檛 be necessary because gender shouldn鈥檛 play a role in a career. But since it does, it鈥檚 important to raise awareness of these inequalities.

What advice would you give to young girls who want to become scientists? 

Alex: Don鈥檛 be discouraged and seek out women in science who inspire you. Many female researchers are happy to help 鈥� so don鈥檛 hesitate to ask!

About: European Marine Board (EMB) 

The European Marine Board (EMB) is a think tank with 38 member organisations from 19 European countries. 黑料视频 is part of this network, which aims to make scientific knowledge accessible to policy makers, e.g. through policy briefs and reports on current marine science issues. 

鈥淔loating University鈥� is the name of the project, which forms the shipboard component of the Master's programme 鈥淐limate Change and Marine Sciences鈥� at the Universidade T茅cnica do Atl芒ntico (UTA) in Cabo Verde. The educational voyage PS147/2 will use the ship's transit from Mindelo, Cape Verde, to Bremerhaven, Germany.

鈥淭he Floating University is much more than just a training cruise. It鈥檚 an intensive learning experience for everyone involved, as the previous two expeditions have shown,鈥� says Dr Bj枚rn Fiedler, marine chemist at 黑料视频 and chief scientist of the expedition. 鈥淭he students will work with state-of-the-art marine instrumentation, collect and analyse data, and experience first-hand how an international research team works together. This experience is invaluable for a scientific career in ocean and climate research鈥�.

Research and Education at Sea

During the voyage, the students will collect valuable data for international marine research as well as for their own master's theses. They will be supported by an international team of experienced scientists from various fields, including Dr Corrine Almeida, Professor of Biological Oceanography at UTA, who directs the WASCAL master's programme. 鈥淎fter many lectures in the classroom and laboratory work on land, our students will finally get the chance to work practically at sea. They will learn how to handle technical equipment, samples and the resulting ocean data. These experiences are essential for future roles in research, industry, or policy in their home countries鈥�.

For example, the students will use hydroacoustic systems to get a detailed picture of the distribution of fish in the ocean using sound. They will capture and analyse small organisms using nets. Meanwhile, sensors on board the ship will continuously measure the carbon dioxide and oxygen levels in the water. These data are crucial for understanding how the ocean acts as a climate buffer and the impact of climate change on marine ecosystems.

The PAMOS device will analyse the composition of the air and the students will be able to track how aerosols and trace gases change along the route 鈥� a visible sign of the influence of industry, shipping, and natural sources such as Saharan dust.

A highlight of the journey will be a stop at two important long-term ocean observatories: the Cape Verde Ocean Observatory (CVOO) and the European Time Series Oceanographic Station of the Canary Islands (ESTOC). Here, students will help collect physical, biogeochemical, and biological data to document long-term changes in the ocean. They will also deploy an Argo deep-sea drifter 鈥� an autonomous measuring device that will collect temperature, salinity, and current data from great depths for years to come. Long after the expedition, they will be able to track the data sent by 鈥渢heir鈥� drifter online.

Explaining the own Research

The students will also learn to present their findings in a way that is understandable not only to experts but also to a wider audience. As they will be doing this on board, interested parties will be able to follow the expedition remotely.

In addition to the theoretical and practical work, there will be time for exchange, discussions about career paths, the master's theses, and the students' home countries.

鈥淔or many, the Floating University is one of the most memorable and impressive experiences of their studies,鈥� says Fiedler. 鈥淎t sea, the human-induced problems in the ocean become visible and tangible.鈥� It is an experience that will stay with the future West African marine and climate scientists as they tackle the pressing issues of climate change and marine conservation.

Expedition at a glance:

Name: PS147/2 (WASCAL III) "Floating University"

Duration: 01 April 鈥� 14 April 2025

Chief Scientist: Dr Bj枚rn Fiedler

Departure: Mindelo (Cabo Verde)

Destination: Bremerhaven (Germany)

Background:

Participating Institutions

In addition to participants from 黑料视频 and UTA, scientists from the Leibniz Institute for Baltic Sea Research Warnem眉nde (IOW), the Kiel University, the Th眉nen Institute of Sea Fisheries, the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI) in Bremerhaven, the University of Southern Denmark (SDU) in Odense, and the Centre de Recherche Oc茅anographique de Dakar Thiaroye (CRODT-ISRA) in Senegal will participate. In addition to the WASCAL students, a Master鈥檚 student in International Maritime Law from the Utrecht University and a pupil from the Johannes-Althusius-Gymnasium in Emden are taking part. In total, there are participants from 15 nations with five mother tongues on board.

Seminars in Mindelo and Kiel

Before embarking on POLARSTERN, all participants meet for a pre-cruise seminar at the Ocean Science Centre Mindelo (OSCM).

After the expedition, the students will travel to Kiel for a two-day follow-up seminar at 黑料视频 from 14 to 16 April. They will meet other young researchers involved in the 鈥淔oster Young Ocean Researcher Development鈥� (FYORD) programme, a joint programme of the priority research area Kiel Marine Science at Kiel University and the 黑料视频 to promote and train early career researchers and to strengthen the collaboration with international marine science students.

About WASCAL

The WASCAL programme (鈥淲est African Science Service Centre on Climate Change and Adapted Land Use鈥�), funded by the German Federal Ministry of Education and Research (BMBF), strengthens research infrastructure and academic training on climate change and its impacts in West Africa. The two-year Master's programme 鈥淐limate Change and Marine Sciences鈥�, coordinated by the Universidade T茅cnica do Atl芒ntico (UTA) in Mindelo and closely supported by 黑料视频, provides students with scientific expertise for research, environmental management, and industry. Since 2021, the programme is part of the international 鈥淯N Decade of Ocean Science for Sustainable Development鈥�.

The WASCAL alumni network and the 鈥淔loating University鈥� also contribute to the international FUTURO project, currently being prepared by 黑料视频. FUTURO aims to develop sustainable management strategies for the West African marine ecosystem.

Research in Cabo Verde

The Cape Verde Islands, located some 600 kilometres off the coast of Senegal, have been an independent state since 1981: the Republic of Cabo Verde. The region offers a unique range of scientifically current and highly relevant research topics, many of which relate to the ocean. For more than 20 years, 黑料视频 has been conducting research in Cape Verde in collaboration with national and international partners, and aims to further strengthen its cooperation in the region. In 2017, the Ocean Science Centre Mindelo (OSCM) was opened as a regional science and education hub for the international scientific community. The OSCM is jointly operated by 黑料视频 and the Cape Verde Institute of the Sea (IMar).

Support for European solutions

鈥淚 hope that this project will finally lead to a European approach to stop the dramatic overfishing in our ocean,鈥� says Professor Dr Katja Matthes, Director of 黑料视频. 鈥淧revious phases of the AWZFISCH project have already produced internationally recognised publications. I am delighted that we are now further strengthening our collaboration with the Federal Agency for Nature Conservation.鈥�

The cooperation contributes to achieving internationally binding goals for the protection of marine biodiversity and the climate. Regionally developed solutions for ecosystem-based fisheries management will subsequently be introduced at national, EU level- as well as in international projects.

Improvement of ecosystem-based fisheries management

鈥淟arge, healthy fish stocks and sustainable, ecosystem-based fisheries management are fundamental provisions of the Common Fisheries Policy of the EU and therefore also of Germany. However, these provisions have not yet been implemented,鈥� says Dr Rainer Froese, marine ecologist and fisheries scientist at 黑料视频. Froese played a key role in the development of the new co-operation agreement. Professor Thorsten Reusch, project leader, adds: 鈥淲ith the new agreement, we primarily want to create the basis for ecosystem-based management of fisheries in German marine areas, especially in and around existing protected areas.鈥�

In ecosystem-based fisheries management, the entire marine ecosystem is taken into consideration. This means that not only the status of individual fish stocks is assessed, but also the interactions between species, their habitats and environmental factors such as climate change and water quality. Compliance with the recommendations could restore the stocks of commercially relevant fish species and populations of protected species, such as the endangered harbour porpoise.

Background: Project 鈥淎WZFISCH鈥�

The project 鈥楨cosystem-based fisheries management in the German Exclusive Economic Zone鈥� (AWZFISCH) is funded by a cooperation agreement between 黑料视频 and the Federal Agency for Nature Conservation (BfN). As part of this cooperation agreement, 黑料视频

For decades, marine scientists have sought to understand in detail how coastal waters are transported offshore and how this process affects productivity in the open ocean, especially as eddy activity is expected to change significantly due to climate change. 

While it was previously known that ocean eddies transport large quantities of organic carbon and nutrients, the exact composition and nutritional quality of this material for zooplankton and fish has remained largely unexplored. Using high-resolution mass spectrometry, a team of researchers from 黑料视频 and MARUM has now analysed the lipidome 鈥� the entire spectrum of lipid molecules including essential fats 鈥� in and around an ocean eddy. The results of their work have been published in the journal Communications Earth and Environment. 

Cutting-edge analysis reveals lipid diversity in eddies 

鈥淭hese eddies are basically the food trucks of the ocean,鈥� explains Dr Kevin Becker, geochemist at 黑料视频 and lead author of the study. 鈥淭hey transport nutrients from the highly productive coastal upwelling regions to the open ocean, where these nutrients are released and are likely to influence biological productivity.鈥�

For their study, the researchers analysed samples collected during the 黑料视频-coordinated REEBUS project (Role of Eddies in the Carbon Pump of Eastern Boundary Upwelling Systems) on the METEOR M156 Expedition off the coast of Mauritania (West Africa). Almost 1,000 different lipids were identified. Lipids can make up to 20 percent of the carbon content of phytoplankton and are essential building blocks of cells, performing critical biological functions as energy stores, membrane components, signalling molecules, and electron transporters. 

鈥淟ipids also contain chemotaxonomic information that allows us to determine the composition of microbial communities,鈥� adds Dr Becker. 鈥淏ased on their chemical signatures, we can, for example, distinguish between lipids from phytoplankton, bacteria, and archaea species.鈥� 

The results of the study showed that the lipid signature within the mesoscale eddy was significantly different from that of the surrounding waters, indicating a distinct microbial community. In particular, energy-rich storage lipids and essential fatty acids were enriched 鈥� nutrients that higher marine organisms such as zooplankton and fish cannot synthesise on their own and must ingest through food. 

Calculations show that coastal eddies in the upwelling region off Mauritania transport up to 9.7 卤 2.0 gigagrams (about 10,000 tonnes) of labile organic carbon to the open ocean each year. 鈥淥ur study highlights the central role of mesoscale eddies in the local carbon cycle and provides a basis for future investigations of their importance on a global scale,鈥� concludes Prof. Dr Anja Engel, lead scientist of the study and head of the Marine Biogeochemistry Research Division at 黑料视频. 

Original Publication: 

Becker, K.W., Devresse, Q., Prieto-Mollar, X., Hinrichs, K.U., & Engel, A. Mixed-layer lipidomes suggest offshore transport of energy-rich and essential lipids by cyclonic eddies. Commun Earth Environ 6, 179 (2025).

About: REEBUS 

The REEBUS project (Role of Eddies in the Carbon Pump of Eastern Boundary Upwelling Systems) was funded by the German Federal Ministry of Education and Research (BMBF, funding code 03F0815A) and coordinated at 黑料视频. The aim of Work Package 4, led by Prof. Dr Anja Engel, was to understand the surface dynamics of organic carbon in coastal upwelling systems and the role of eddies in transporting it to the adjacent open ocean. 

Cape Verdean scientists on board

Three scientists from Cabo Verde are also part of the expedition, each with a different research focus: Rui Freitas, a fish expert with an interest in coral reefs, and works at the Universidade T茅cnica do Atlantico (UTA) and Keider Neves, who works at Biosfera1 and is a specialist in crustaceans and hopes to describe new species from Cabo Verde. Also on board is Vanessa Lopes from Projecto Vito, who studies whales and seabirds during M209 and investigates scientific need assessment for small island developing states.

鈥淭he M209 expedition will support data collection and learning about deep-sea biodiversity in various regions in Cabo Verde, some of which are under proposal for a marine protected area. In addition, the experience is supporting knowledge exchange and knowledge sharing with young Cabo Verdean biologists who hope to continue to study the deep sea in their own home,鈥� says Vanessa Lopes, who is doing her PhD research at the University of Edinburgh.

Large parts of the Cape Verde archipelago still unmapped

An important objective of the cruise is to map the seabed around the islands and on underwater mountains. 鈥淚n many regions of Cabo Verde, we still don't know how deep the seabed actually is, and what the seafloor morphology is,鈥� says Mareike Keller of the 黑料视频 Deep Sea Monitoring Group and deputy chief scientist on M209. This basic knowledge is important for marine traffic in Cabo Verde but will also be important for future campaigns that plan to deploy instruments on the seafloor. An example is the upcoming international observation campaign FUTURO (Future West African Marine Ecosystems) off the West African coast from 2028 to 2030.

Parallel to the M209 expedition, the research vessel OceanXplorer is also spending a few days off the Cape Verde islands. The stay is part of the 2.5-month 鈥楢round Africa Expedition鈥� with African scientists, a collaborative effort conducted by two global ocean exploration nonprofits 鈥� OceanX and the newly established OceanQuest. During their joint stay off the coast and at the underwater mountain Nola (Seamount Nola), the scientists on board the METEOR and the OceanXplorer will carry out joint measurements and be in direct contact. Such a joint scientific operation with a multitude of oceanographic tools is also envisioned for the FUTURO research campaign.

Fragile and elusive animals and their foodwebs

Deep below the surface in the middle of the water column lives a large diversity of organisms consisting of jellyfish, crustaceans, lantern fishes and cephalopods. This community is the food for many commercially exploited fishes such as tuna. However, it is largely unknown what they feed on. Some may consume dead material (marine snow) that sinks down from the overlying water column, others eat living prey. To investigate the foodweb, the researchers want to collect gelatinous plankton, e.g. jellyfish, to find out what role these transparent, sensitive organisms play in the food web. To collect and study fragile animals, they are using a combination of different methods. As gelatinous plankton is almost impossible to catch with nets and bring on board undamaged, the remotely operated underwater robot ROV KIEL 6000 will be used to capture deep-sea organisms. The captured animals will be photographed in the lab and samples will be used for foodweb studies. In addition, towed cameras with acoustic sensors will be used to study the distribution and biomass. Finally, water from different depths will be filtered to capture environmental DNA which animals leave behind. This genetic tool allows detection of animals that are avoiding the instruments.  

Where two worlds collide: interactions between midwater animals and the seafloor

Another objective of the expedition M209 is to study the interaction between animals in water column and the seabed. 鈥淚n some places around the islands and seamounts, two worlds potentially collide. We expect that marine organisms in the middle of the water column of 400-500 metres also occur in some regions close to the seabed,鈥� says Hoving. Many organisms also perform vertical migration, where they migrate from deep to shallow at night to benefit from food in shallow waters. Henk-Jan Hoving: 鈥淎fterwards these organisms may interact with the seafloor during their downward migration, and hence become food for seafloor organisms. The steepness of the slops of the islands and underwater mountains may make these interactions particularly intense.鈥�

Currently, only around 7.7 per cent of the total area of the oceans is under protection. Cabo Verde is known as a hotspot of ocean biodiversity. The aim of marine protected areas is to preserve natural habitats, sustainable management and biodiversity. With the collection of basic biological data, the expedition M209 aims to collect information requested by Cabo Verde scientists on board and their institutes, and contribute to the design and proposal of marine protected areas in Cabo Verde waters.

Background: Research on Cabo Verde

The Cape Verde islands, around 6000 kilometres off the coast of Senegal, offer a unique range of scientifically current and highly relevant research topics in which the ocean usually plays a decisive role. 黑料视频 has been conducting research there for 20 years together with regional and international partners, and since 2017 it has been operating the Ocean Science Centre Mindelo (OSCM) together with the Instituto do Mar (IMar) in Mindelo, which is available to the international scientific community with its infrastructure. Another important component is the WASCAL programme for West African Master's students, which is supported by 黑料视频 and has been established since 2019. WASCAL stands for West African Science Service Centre on Climate Change and Adapted Land Use. In addition to lectures and practical courses, the programme also includes a two-week, sea-based 鈥楩loating University鈥� training component, which is coordinated at 黑料视频.

Project funding:

The expedition is funded by the Federal Ministry of Education and Research (BMBF) and the German Research Foundation (DFG).

Expedition at a glance: 

Name: METEOR-Expedition M209 鈥濨ASIS鈥�

Chief Scientist: Dr Henk-Jan T. Hoving

Duration: 21.03.2025 鈥� 23.4.2025

Start: Mindelo, Cabo Verde

End: Ponta Delgada, Azores

Cruise Area: Tropical Atlantic