OAeSIS adopts an integrated, interdisciplinary methodology structured around five research themes aligned with the project’s core objectives:

1. Identify the social, ethical and governance constraints on OAE deployment.
2. Improve understanding of the biogeochemical processes and interactions triggered by OAE deployment.
3. Quantify the scaling potential of OAE deployments and their climate change mitigation capacity.
4. Quantify the impacts of OAE on key calcifying species, communities and biodiversity.
5. Assess the feasibility and sustainability of OAE as a tool for counteracting climate change and ocean acidification

CMCC role
WP leader of WP 14, WP 15, WP 16, WP 17, WP 18.
Contribution in WP 1; WP 2; WP 6; WP 7; WP 8; WP 10; WP 11; WP 12; WP 13.

Activities
The project aims to conduct in-situ observations at three sites:
a) the SeaCURE pilot plant in Weymouth Bay (UK) for short-term effects
b) the Bülk/Kiel sewage treatment outfall in the Baltic Sea (Germany) for medium-term impacts
c) the Krka River estuary (Croatia) for long-term alkalinity dynamics.

A range of tried and tested established model systems will be used to address each scale with the resolution necessary to resolve the relevant processes:

• high resolution (<100 m scale): local domains suitable for sub-meso-scale features and fully resolving the complex mixing dynamics characterising near field impacts of individual OAE projects
  regional domains (1.5–7 km) for assessing multi-national clusters of OAE operations
• global ocean and fully coupled Earth System Models (1 degree resolution) for upscaling to global OAE activities and assessing fully upscaled long term efficacy
• Life Cycle Assessment – IAM–ESM modelling chain to explore pathways to OAE sustainability

To achieve these goals OAeSIS engages a diverse, interdisciplinary team of leading experts in law, governance and socioeconomic assessments of the climate-biodiversity and ocean nexus, laboratory and field studies on the biogeochemistry of OAE, the stressors that affect individual organisms, communities and biodiversity, climate and biogeochemical modelling, integrated assessment modelling and life cycle assessment.

Combining and integrating this expertise will enable the simultaneous improvement of scientific knowledge, provide understanding and guidance on social acceptance, regulation and governance, and increase the policy relevance of project outputs.

In doing so, the project will advance the ability to evaluate the benefits and impacts associated with OAE, enabling informed decision- and policy-making regarding the potential application of this leading mCDR approach as a climate mitigation tool.

Expected results
OAeSIS will generate knowledge and data to support robust assessments of Ocean Alkalinity Enhancement and to inform pathways toward implementation that are effective, sustainable, and just. This will be achieved through a step change in understanding biogeochemical responses to different OAE deployment options, their efficacy at scale, and potential impacts on marine biology and biodiversity; the strengthening of European observing and modelling infrastructures to monitor OAE across spatial and temporal scales; and the development of sustainable implementation pathways, governance frameworks, and engagement strategies aimed at ensuring fair and equitable deployment.

The project will contribute to key EU policy objectives, including:

• Achieving a climate-neutral Europe by 2050, as set out in the European Climate Law.
• Halting and reversing biodiversity loss, in line with the European Green Deal and the Kunming–Montreal Global Biodiversity Framework.
• Building a fair and inclusive Europe that protects citizens and expands opportunities, as outlined in the European Pillar of Social Rights Action Plan.

OAeSIS will also support broader global sustainability frameworks, including the UN Sustainable Development Goals, the Paris Agreement, and the Convention on Biological Diversity.

Partners
National Oceanography Centre [UK partner]
Paul Scherrer Institut [CH partner]
University of Waterloo [Canada partner]
Plymouth Marine Laboratory [UK partner]
Ruder Boskovic Institute [HR partner]
Goeteborgs Universitet [SE partner]
Barcelona Supercomputing Center [ES partner]
University of Hamburg [DE partner]