The state of the global ocean

Here, the Copernicus Ocean State Report offers detailed scientific analysis of the ocean under climate change, ocean variability, and ocean extremes. This evidence-based reporting is based on a set of key ocean indicators such as sea surface temperature, sea level rise, ocean heat content, ocean acidification, and sea ice extent. Moreover, key indicators for ocean variability such as the El Niño–Southern Oscillation and major ocean current systems such as the Atlantic Meridional Overturning Circulation are tackled. Major results show that the global ocean's sea surface temperature continues to steadily increase, particularly in the Northern Hemisphere, with a global warming rate of 0.13 ± 0.01 °C per decade from 1982 to 2023. Since around the 1970s, the ocean warming trend has intensified, doubling its rate over the past 2 decades. Concurrently, global mean sea level has risen significantly at intensifying rates from 2.1 mm yr−1 in the 1990s to 4.3 mm yr−1 in recent years, with regional disparities. The Arcti