This annual report provides authoritative information on the state of the climate system by updating key observed climate indicators and presenting selected high-impact weather and climate events. For the first time, the report includes the Earth’s energy imbalance as one of the key climate indicators. The report covers:

• key observed global climate indicators: global temperature, greenhouse gases, ocean heat, sea level, ocean pH, sea-ice extent, glacier mass balance and a new indicator on Earth’s energy imbalance
• high-impact weather and climate events of 2025: heat and cold extremes, floods, droughts, tropical cyclones
• case study: climate and heat impacts on health
• data sources and methods: detailed information about the data sources and processing.

Extreme events around the world, including intense heat, heavy rainfall and tropical cyclones, caused disruption and devastation and highlighted the vulnerability of inter-connected economies and societies. 

The report is provided with an interactive story map and an extremes supplement on extreme events, highlighting their cascading impacts, including on food insecurity and displacement.

Key findings

• Earth’s energy imbalance is at its highest level on record.
• The past 11 years are the warmest on record, and 2025 was among the three warmest globally.
• The ocean is warmer and more acidic than ever in the observed record.
• Climate extremes are posing growing risks to lives, food security, health and economies.