The ocean absorbs about 30% of human-caused carbon dioxide emissions and around 90% of the excess heat trapped by global warming. However, rising temperatures and changing ocean chemistry are putting pressure on its ability to regulate the climate, according to a United Nations report released on Oct. 28, 2026.

The 2026 Climate Technology Progress Report calls for greater investment in Ocean Carbon Intelligence. The framework combines ocean science, monitoring systems, data infrastructure and analytical tools. Its goal is to improve understanding of how the ocean absorbs, transports and stores carbon.

The report was produced by the UNEP Copenhagen Climate Centre, the Climate Technology Centre and Network, and the UN Framework Convention on Climate Change Technology Executive Committee.

Why Ocean Carbon Storage Matters

The ocean is one of Earth's largest carbon sinks. It removes a substantial share of human-generated carbon dioxide from the atmosphere. It also absorbs most of the excess heat associated with global warming.

But warming waters, ocean acidification, declining oxygen levels, pollution and ecosystem damage threaten marine environments. These pressures can alter the physical, chemical and biological processes that control carbon storage.

UNEP climate change division director Martin Krause said a weaker ocean carbon sink could leave more carbon dioxide in the atmosphere. He warned that this could make climate targets harder and more expensive to achieve.

Ocean Carbon Intelligence And Climate Technology

The report identifies gaps in ocean observations, data sharing and scientific modelling. These limitations make it harder for governments and investors to assess risks and evaluate ocean-based climate technologies.

Ocean Carbon Intelligence aims to connect these systems. Better monitoring and reliable data could support climate planning and help researchers assess changes in carbon storage.

Potential technologies include restoring blue carbon ecosystems, such as mangroves, seagrasses and tidal marshes. Emerging marine carbon dioxide removal methods are also under consideration. Their effectiveness and environmental impacts require careful assessment.

Emissions Cuts Remain Essential

The report states that ocean-based climate technologies must complement, not replace, rapid and sustained reductions in greenhouse gas emissions. It calls for scientific oversight, transparency, environmental safeguards and effective governance.

Pacific COP31 Ocean Envoy Inia Seruiratu also highlighted the need for international cooperation, sustained investment and the integration of Indigenous knowledge.

The report's central message is that stronger ocean science can improve climate decisions. However, responsible deployment of ocean technologies will depend on reliable evidence, public trust and long-term investment.