‘Profound impacts’: record ocean heat is intensifying climate disasters, data shows
Oceans absorb 90% of global heating, making them a stark indicator of the relentless march of the climate crisis
TL;DR
- Oceans absorbed a record amount of heat in 2025.
- Over 90% of heat trapped by carbon pollution is absorbed by oceans.
- Ocean heat is a key indicator of the climate crisis.
- Excess heat leads to more intense hurricanes, heavier rainfall, flooding, and marine heatwaves.
- Rising ocean heat contributes to sea-level rise through thermal expansion.
- Oceans are likely the hottest in 1,000 years and warming faster than in 2,000 years.
- Atmospheric temperature in 2025 is expected to tie with 2023 as the second-hottest year on record.
- The amount of heat absorbed by the ocean is equivalent to over 200 times humanity's total electricity usage.
- Warming is not uniform, with tropical and South Atlantic, North Pacific, and Southern Oceans showing faster increases.
- The North Atlantic and Mediterranean Sea are warming, becoming saltier, more acidic, and less oxygenated.
- Ocean warming makes marine ecosystems more fragile.