黑料视频

Avoiding emissions is the primary goal on the path to climate neutrality. However, with the need to offset hard-to-avoid CO₂ emissions in the future by removing CO₂ from the atmosphere, ocean-based carbon dioxide removal (CDR) and storage methods are attracting increasing attention. But what opportunities does Germany have to utilise its marine areas for this purpose? This question has been addressed in a new study, in which researchers have for the first time attempted to assess the feasibility of ocean-based CDR and storage in German waters, taking into account local marine conditions as well as where the required materials, infrastructure and energy for such large-scale operations would have to come from.

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.