Overview
- Data that peaked on June 21 showed global average sea-surface temperatures at about 20.86°C to 21.0°C, exceeding June highs set in 2023 and 2024 according to two Copernicus datasets.
- Copernicus scientists said the first half of 2026 featured sustained, exceptional ocean warmth with marine heatwaves affecting roughly 82 percent of the global ocean.
- Regional hotspots set new benchmarks, with the Mediterranean reaching about 24.3°C and the tropical Pacific about 27.26°C, driving coral bleaching and threats to fisheries.
- Copernicus directors including Carlo Buontempo and lead oceanographer Simon van Gennip warned that the developing El Niño on top of human-driven warming makes further temperature and weather extremes more likely in the coming months.
- The record draws on satellite, ship and buoy observations and underlines that oceans absorb roughly 90 percent of excess heat from greenhouse gases, a factor that raises storm intensity, heavy rainfall risk, sea-level rise and direct impacts on coastal communities and marine livelihoods.