A new study revealed that the world's oceans absorbed a record-breaking 23 zettajoules of heat in 2025, marking the eighth consecutive year of increasing ocean heat absorption. The research, published Friday in the journal Advances in Atmospheric Science, indicated a significant increase from the 16 zettajoules absorbed in 2024.

The team of over 50 scientists from the United States, Europe, and China conducted the study, analyzing data collected since 2018 to measure the amount of heat absorbed by the world's oceans each year. Their findings showed a consistent upward trend, with 2025 setting a new high since modern measurements began in the 1960s.

A joule, a standard unit of energy measurement, is equivalent to the energy needed to power a small lightbulb for one second or slightly heat a gram of water. A zettajoule, however, is one sextillion joules, illustrating the massive scale of energy accumulation within the oceans. The 23 zettajoules absorbed in 2025 can be written as 23,000,000,000,000,000,000,000 joules.

The increasing ocean heat has far-reaching implications for the global climate system. Warmer oceans contribute to rising sea levels through thermal expansion, intensify extreme weather events such as hurricanes and typhoons, and disrupt marine ecosystems. The absorption of excess heat also affects ocean currents and weather patterns worldwide.

Scientists are using increasingly sophisticated AI models to analyze ocean temperature data and predict future trends. These models help researchers understand the complex interactions within the ocean and atmosphere, providing valuable insights for climate mitigation and adaptation strategies. The latest developments in AI-driven climate modeling are enabling more accurate projections of sea-level rise, ocean acidification, and changes in marine biodiversity.