The Ocean at the UN Climate Change Conference

Standing on the coast of Antalya, one looks out over a sea that is undergoing particularly rapid changes as a result of climate change. The Mediterranean is warming faster than the global ocean. According to the EU’s Copernicus Climate Change Service, the surface temperature of the Mediterranean has risen by around 1.4 degrees since the 1980s, compared with around 0.6 degrees globally.Turkey will host the World Climate Conference (Conference of the Parties, COP31) here from 9 to 20 November 2026. More than 80,000 participants from 196 countries are expected to attend. The focus will be on limiting global warming, adapting to the consequences of climate change and financing climate protection measures.

“Oceans and Seas” at COP31

‘Oceans and Seas’ is one of the ten key themes of the COP31 Presidency. Together with international partner institutions, scientists from the GEOMAR Helmholtz Centre for Ocean Research Kiel will be contributing their expertise at the Ocean Pavilion in the so-called Blue Zone – the official area where the negotiations also take place. 

The Turkish Presidency also aims to secure a joint ocean declaration by the participating states in Antalya – the Antalya Ocean Declaration. This is intended to advance climate action with the help of the oceans and to assist vulnerable coastal and island states in adapting to climate change. According to the latest Emissions Gap Report by the United Nations Environment Programme (UNEP), the measures taken so far are insufficient to meet the targets of the Paris Agreement. In this agreement, the signatory states have committed to limiting global warming to 1.5 degrees above pre-industrial levels as far as possible. If countries continue with their current policies, the Earth could warm by 2.8 degrees this century. The report assumes that exceeding the 1.5-degree threshold is now inevitable. The aim is now to keep this overshoot as small and short-lived as possible and to bring global warming back down to 1.5 degrees by the end of the century. 

“Every tenth of a degree we avoid counts. It is not too late to limit the consequences for the ocean and for us humans. To achieve this, emissions must fall rapidly and significantly now. The World Climate Conference in Antalya is an opportunity to reaffirm international cooperation towards this goal,” says Prof. Dr Katja Matthes, Director of GEOMAR. 

The ocean as a carbon sink under pressure

The ocean acts as a buffer against climate change: since the start of the Industrial Revolution, it has absorbed around 30 per cent of the carbon dioxide (CO_₂) produced by humans. However, this capacity is waning. According to the Climate Technology Progress Report by the United Nations Environment Programme (UNEP), climate change is already causing the ocean to absorb around six per cent less carbon than it otherwise could. Dr Judith Ziegler from GEOMAR is a co-author of one of the chapters and will be presenting the report alongside other authors in the Ocean Pavilion.

Blue Carbon: Marine ecosystems contribute to climate protection

Seagrass beds, salt marshes and mangroves sequester carbon. The protection of these so-called blue carbon ecosystems and their contribution to climate protection are among the key priorities of the COP31 Action Agenda. Many countries have already incorporated coastal ecosystems into their national climate action plans (Nationally Determined Contributions, NDCs). Katja Matthes will be discussing with international experts in the Ocean Pavilion how their carbon sequestration potential can be better utilised and monitored, and what research and policy frameworks are required to achieve this. GEOMAR is also organising an event on climate protection and coastal ecosystems in the German Climate Pavilion, in collaboration with the German Federal Environmental Foundation (DBU).

Ocean observation

Another panel discussion involving GEOMAR will focus on the value of ocean observation for society, the economy and the financial sector. Ocean measurements help, for example, to predict flooding and detect marine heatwaves at an early stage. The data also provide key insights into long-term developments in the climate system, such as changes to the Atlantic Meridional Overturning Circulation (AMOC). At the end of September, the European Union and Canada founded the international OceanEye alliance. Its aim is to strengthen the Global Ocean Observing System (GOOS) and ensure its long-term sustainability. 

Katja Matthes: “Only by building on detailed observational data can we make sustainable decisions regarding the protection and use of the ocean. This knowledge is not only relevant to research: without this data, it is impossible to forecast the weather, plan shipping routes or issue early warnings of earthquakes and tsunamis.”

GEOMAR experts on site

Prof. Dr Katja Matthes, Director of GEOMAR
Expertise: Climate research and the ocean, sustainable use of the ocean, deep-sea mining, international cooperation

Dr Judith Ziegler, Scientific Project Manager at GEOMAR
Expertise: Carbon uptake in the ocean

 Dr Toste Tanhua, Chemical Oceanographer at GEOMAR
Expertise: Ocean observation

Events involving GEOMAR (local time in Antalya, UTC+3)

Thursday, 12 November 2026, 10.30–11.30, German Climate Pavilion: Where Blue Meets Green: Synergies between Climate Mitigation and Coastal Ecosystems (event organised by the DBU and GEOMAR with Prof. Dr Katja Matthes)

Thursday, 12 November 2026, 12.45–13.35, Ocean Pavilion: Harnessing Synergies and Strengthening the Role of the Ocean in NDCs (with Prof. Dr Katja Matthes)

Friday, 13 November 2026, 10.15 am to 11.05 am, Ocean Pavilion: A Close Eye on our Ally: Unlocking the Social, Economic and Financial Values of Ocean Observation (with Prof. Dr Katja Matthes)

Tuesday, 17 November 2026, 10.15 am to 11.05 am, Ocean Pavilion: Navigating Ocean-based Technologies: The 2026 Climate Technology Progress Report (CTPR) (with Dr Judith Ziegler)

Background

The COP31 Climate Change Conference

The 31st UN Climate Change Conference, the ‘Conference of the Parties’ (COP), will take place from 9 to 20 November 2026 in Antalya, Turkey. The conference aims to strengthen global commitment to climate action in order to limit global warming and drive forward climate adaptation measures. It also aims to disseminate practical solutions and translate commitments into tangible actions. For the first time, the duties of the presidency are shared between two countries: Turkey holds the presidency and is hosting the conference. Australia is leading the actual negotiations, in which national governments decide on binding rules for climate action. Turkey is also responsible for the Action Agenda, which complements these negotiations. It brings together non-state actors such as cities, businesses, investors, indigenous peoples and civil society to discuss practical solutions.

Ocean Pavilion

The Ocean Pavilion is organised by the Woods Hole Oceanographic Institution and the Scripps Institution of Oceanography at the University of California, San Diego. It is a dedicated area within the Blue Zone at COP31, designed to bring the ocean more firmly into the climate negotiations. The Ocean Pavilion brings together stakeholders committed to ensuring that ocean-based solutions are recognised as crucial to the world’s response to the climate crisis. During the two-week conference, the pavilion will host more than 65 events.