BEIJING, China — The world’s oceans absorbed more heat in 2025 than in any other year since modern measurements began, setting a new and troubling record that highlights the accelerating pace of global warming, according to a major international study released on Friday.
The study, published in the journal Advances in Atmospheric Sciences, found that ocean heat content rose by about 23 zetta joules in 2025 — an amount of energy roughly equivalent to 37 years of total global energy consumption at 2023 levels.
The analysis was conducted by more than 50 scientists from 31 research institutions around the world, drawing on data from leading international climate centers and independent research groups across Asia, Europe, and the Americas.
Researchers concluded that heat content in the upper 2,000 meters of the ocean reached its highest level on record in 2025, continuing a clear and long-term upward trend. Scientists from the Institute of Atmospheric Physics at the Chinese Academy of Sciences, who were part of the research team, said the findings underscore how rapidly the planet is accumulating excess heat.
Ocean warming, however, was not evenly distributed. About 16 percent of the global ocean surface experienced record-high heat last year, while another 33 percent ranked among the three warmest years in recorded history. The fastest warming was observed in the tropical and South Atlantic, the North Pacific, and the Southern Ocean.
While the deep ocean set a new heat record, surface temperatures showed a slightly different pattern. The global average sea-surface temperature in 2025 ranked as the third warmest on record, remaining about 0.5 degrees Celsius above the recent baseline and slightly below the peaks recorded in 2023 and 2024.
Despite not setting a new surface temperature record, the elevated warmth had significant real-world consequences. Researchers said higher sea-surface temperatures contributed to increased evaporation and heavier rainfall, fueling extreme weather events in 2025, including severe flooding in Southeast Asia and Mexico and prolonged drought conditions in parts of the Middle East.
The study warned that continued ocean heating has far-reaching implications. Rising ocean temperatures contribute directly to sea-level rise through thermal expansion, intensify and prolong marine heatwaves, and add heat and moisture to the atmosphere, increasing the strength and frequency of storms and other extreme weather events.
Scientists said that as long as greenhouse gas emissions continue and the Earth’s energy imbalance persists, ocean heat records are likely to keep being broken in the coming years. (Source: IANS)
