♦ The world’s oceans absorbed more heat in 2025 than in any other year since modern record-keeping began, according to a new international study released on 9 January 2026. Published in the journal Advances in Atmospheric Sciences, the study found that ocean heat content rose sharply last year (2025), increasing by about 23 zettajoules of energy — an amount equivalent to roughly 37 years of global energy consumption at 2023 levels.

♦ The research was conducted by more than 50 scientists from 31 institutions worldwide. By combining data from major international centres and independent research groups across Asia, Europe and the Americas, the team concluded that heat stored in the upper 2,000 metres of the ocean reached its highest level on record in 2025, confirming a sustained warming trend.

♦ About 16 percent of the global ocean surface recorded its warmest year ever in 2025, while another 33 percent ranked among the three warmest years in historical records. The most rapid warming was observed in the tropical and South Atlantic, the North Pacific and the Southern Ocean.

♦ While heat stored in the deep ocean set a new record, surface temperatures followed a slightly different pattern. The global average sea-surface temperature in 2025 was the third highest on record, remaining around 0.5 degrees Celsius above the recent baseline and marginally lower than the peaks seen in 2023 and 2024.