UN report warns climate change has weakened ocean carbon sink by 6%

A United Nations report states that climate change has reduced the ocean's capacity to absorb carbon by approximately 6%. The 2026 Climate Technology Progress Report attributes this decline to ocean warming and shifting wind patterns compared to a world without human-induced climate change.

Martin Krause, director of the Climate Change Division at the UN Environment Programme, said a weaker ocean carbon sink leaves more carbon dioxide in the atmosphere. This makes climate goals more difficult and expensive to reach. While the ocean absorbs about 30% of human-induced carbon dioxide emissions and 90% of the additional heat generated by climate change, processes such as acidification, pollution, and ecosystem degradation are disrupting its ability to store carbon.

The report indicates that rapid and sustained reductions in greenhouse gas emissions are the primary response to this weakening. It notes that ocean-based climate technologies are not a replacement for deep emissions cuts or marine ecosystem protection. Instead, these technologies can help preserve natural carbon sinks and improve data for climate decisions. The UN called for continued investment in ocean observation, modeling, and data infrastructure.