WMO will release global temperature figures for 2025 on 14 January 2026, consolidating multiple international datasets to provide a single, authoritative source of information to support climate monitoring and decision-making.
A WMO press release will update its provisional State of the Climate report - which said that 2025 was set to be the second or third warmest year on record - released at the UN Climate Conference, COP30, in Belem, Brazil.
The release is timed to coincide with the global temperature announcements from the dataset providers.
These include the European Center for Medium Range Weather Forecasts Copernicus Climate Change Service (ERA5), Japan Meteorological Agency (JRA-55), NASA (GISTEMP v4), the US National Oceanic and Atmospheric Administration (NOAAGlobalTemp v5), the UK's Met Office in collaboration with the Climatic Research Unit at the University of East Anglia (HadCRUT.5.0.1.0), and Berkeley Earth (USA). There are two additional datasets - DCENT (UK/USA) and CMST (China).
Six of the datasets are based on measurements made at weather stations and by ships and buoys using statistical methods to fill gaps in the data. Two of the datasets - ERA5 and JRA - are reanalyses which combine past observations, including satellite data, with models to generate consistent time series of multiple climate variables including temperature.
The six key datasets all use slightly differing methodologies and so have slightly different temperature figures, and even annual rankings. WMO - the UN agency for weather, climate and water - seeks to provide a consolidated figure to support decision-making.
