Here is the reformatted article.
2025 Confirmed as One of the Hottest Years, Oceans Absorb Record Heat
A synthesis of global climate data from multiple scientific organizations indicates that 2025 was one of the three hottest years on record for global surface temperatures, while the world's oceans absorbed a record amount of heat for the ninth consecutive year. The findings underscore a sustained long-term warming trend, with scientists projecting a high likelihood of exceeding the 1.5°C warming threshold established by the Paris Agreement within this decade.
Global Surface Temperatures in 2025
According to data compiled by the World Meteorological Organization (WMO), the European Union's Copernicus climate service, the UK Met Office, NASA, and NOAA, the global average temperature in 2025 was between 1.4°C and 1.48°C above pre-industrial levels (late 19th century).
Different datasets report minor variations in the precise ranking, with 2025 being calculated as either the second or third hottest year on record, following the record-setting year of 2024. The WMO’s consolidated analysis placed 2025 approximately 1.44°C above pre-industrial levels.
The period from 2015 to 2025 constitutes the 11 hottest years on record. The three years from 2023 to 2025 collectively represent the warmest three-year period ever recorded.
January 2025 was the hottest January on record, and several other months were among the warmest ever observed.
Ocean Heat and Earth's Energy Imbalance
The world's oceans absorbed a record amount of heat in 2025, according to a study published in Advances in Atmospheric Sciences. This marks the ninth consecutive year of record-high ocean heat content.
The oceans absorbed an additional 23 zettajoules (ZJ) of heat, a figure that surpasses the 16 ZJ absorbed in 2024. This is equivalent to more than 200 times the total global electricity consumption by humans.
The WMO's annual State of the Global Climate report included, for the first time, a measure of the Earth's energy imbalance (EEI). The report found that EEI reached its highest level since observations began in 1960, driven by increasing concentrations of heat-trapping greenhouse gases. This imbalance indicates that the Earth system is accumulating more heat than it is radiating back into space.
Over 90% of this excess heat is absorbed by the oceans. The rate of ocean warming has more than doubled in the last two decades compared to the previous 45-year average. The remaining heat is absorbed by land (5%), melts ice (3%), and warms the atmosphere (1%).
Factors Influencing 2025 Temperatures
Natural climate variability, specifically the El Niño-Southern Oscillation (ENSO), continues to influence annual global temperatures.
- The strong El Niño event that influenced global temperatures in 2023 and 2024 weakened and transitioned to a La Niña phase during 2025.
- Scientists state that this La Niña likely prevented 2025 from surpassing 2024 as the hottest year on record.
- Despite this cooling influence, scientists noted that global temperatures remained at exceptionally high levels.
- The WMO and NOAA estimate a high probability (96%) of an El Niño event forming by late 2026, with a 35% chance of a strong "super El Niño."
Scientists cited potential additional factors that may have contributed to the recent temperature rise, including changes in cloud cover and aerosols (such as reduced soot pollution from ships), as well as peak solar activity.
Projections for the 1.5°C Paris Agreement Threshold
The Paris Agreement, established in 2015, set a goal of limiting long-term global warming to 1.5°C above pre-industrial levels, measured as a 20- to 30-year average. Scientists from the WMO, Copernicus, and the Met Office project that this long-term average threshold is likely to be exceeded by the end of the current decade (around 2029-2030).
- A WMO report predicts a 75% chance that the average temperature for the five-year period from 2026 to 2030 will be more than 1.5°C above the pre-industrial average.
- The same report predicts an 86% chance that at least one year between 2026 and 2030 will surpass 2024 as the hottest on record.
- Scientists state that exceeding the 1.5°C level for a single year or a short period does not mean the Paris Agreement target is permanently breached, but it indicates the planet is nearing that limit.
- Projections indicate that the chance of any single year from 2026 to 2030 exceeding 2°C above the pre-industrial average is less than 1%.
"Exceeding the 1.5°C limit is now considered inevitable, shifting the focus to managing the overshoot and its consequences." — Carlo Buontempo, Director of the Copernicus Climate Change Service
Regional and Environmental Impacts
- Arctic and Antarctic: The Arctic is warming at a rate more than three times faster than the global average, with projected winter temperatures 2.8°C above recent averages over the next five years. Antarctica experienced its hottest year on record in 2025. Polar sea ice cover reached its lowest level since satellite observations began in February 2025.
- Rainfall and Drought: Over the next five years, Northern Europe, the Sahel, Alaska, and Siberia are projected to be wetter than usual, while the Amazon region is expected to be drier than usual.
- Extreme Weather: Scientists reported that extreme weather events persisted in 2025, including the Los Angeles fires, Hurricane Melissa, and significant flooding in Southeast Asia and the Pacific Northwest. Ocean warming contributed to more intense hurricanes and typhoons, heavier rainfall, and prolonged marine heatwaves. Approximately 770 million people experienced record annual heat in 2025.
- Sea Level Rise: Ocean warming causes thermal expansion of seawater, contributing to sea level rise, which is accelerating.
Statements from Scientists and Officials
"Protecting human lives and economies from extreme heat requires reducing fossil fuel use more rapidly, noting that clean power is now cheaper and faster to produce." — Simon Stiell, UN Climate Change Executive Secretary
"The global climate is in a state of emergency... a call to act." — António Guterres, UN Secretary-General
"Future perspectives might view the mid-2020s as relatively cool in retrospect." — Dr. Samantha Burgess, Strategic Climate Lead, Copernicus
"Increasing greenhouse gas concentrations in the atmosphere lead to planetary warming... actions like reducing emissions and adapting society can strongly influence future outcomes." — Prof. Rowan Sutton, Director, Met Office Hadley Centre
"Global warming is ocean warming." — John Abraham, Professor, University of St. Thomas and Co-author of the ocean heat study
"Temperatures remaining significantly high during a La Niña year is a point of concern." — Dr. Zeke Hausfather, Climate Scientist, Berkeley Earth