The world just lived through the 11 hottest years on record — what now?
Summary
The World Meteorological Organization’s State of the Climate Report 2025 finds the past 11 years were the hottest on record. 2025 ranked as the second or third warmest year observed, while atmospheric CO2 and ocean heat reached historic highs. Sea ice in both polar regions was among the lowest since satellite records began. The report introduces Earth’s energy imbalance (EEI) as a metric: in 2025 EEI hit its highest level since observations began in 1960, signalling that the planet is storing more heat than it releases.
Scientists underline that most excess heat — over 91% since the 1970s — is absorbed by the oceans, making EEI a more accurate indicator of long-term warming than surface temperature alone. The past three years show a step change in baseline temperatures consistent with ongoing climate change, with faster melting of glaciers and rising ocean heat being key concerns.
Key Points
- The last 11 years are the warmest on record; 2025 was the second or third warmest year.
- Atmospheric CO2 concentrations and ocean heat reached record levels in 2025.
- Earth’s energy imbalance (EEI) reached its highest recorded level, indicating accelerating heat accumulation.
- Over 91% of excess heat since the 1970s has been absorbed by the oceans, not the atmosphere.
- Antarctic and Arctic sea-ice extents were among the lowest since 1979.
- Short-term temperature fluctuations can mask long-term trends; EEI offers a clearer picture of sustained warming.
- Recent years show a discernible step-change in global temperatures attributable to human-driven climate change.
Context and relevance
This report crystallises multiple climate indicators into a stark picture: greenhouse-gas accumulation, ocean warming and increasing EEI together point to sustained, long-term warming with cascading impacts — sea-level rise, more intense heatwaves, wildfires and disruptions to ecosystems and agriculture. For policymakers and planners, the inclusion of EEI matters because it shows locked-in energy that will continue to drive change even if surface temperatures vary year to year.
For researchers and industry, record ocean heat and reduced polar ice alter risk assessments for coastal infrastructure, fisheries and carbon-cycle feedbacks. For the public and communicators, the report removes ambiguity: the climate system is now storing unprecedented heat, and that heat will shape decades of impacts and adaptation needs.
Author style
Punchy: this is not a rerun of old warnings — it’s a louder alarm. The report elevates EEI as the yardstick we should be watching, and the data suggest we’ve crossed into a warmer baseline that will matter for policy, insurance, infrastructure and everyday life. Read the detail if you care about evidence-based decisions on mitigation and adaptation.
Why should I read this?
Because it’s basically the climate system’s status update — and it’s not cheerful. If you’re into evidence, policy, or planning (or just want to understand why heatwaves and wildfires feel worse), this short read gives you the facts without the spin. It’s the clearest warning yet that the planet is hoarding heat and the consequences will be with us for years.