Copernicus: Warmest March in Europe and lowest Arctic winter sea ice
The Copernicus Climate Change Service (C3S), implemented by the European Centre for Medium-Range Weather Forecasts on behalf of the European Commission with funding from the EU, routinely publishes monthly climate bulletins reporting on the changes observed in global surface air and sea temperatures, sea ice cover and hydrological variables. Most of the reported findings are based on the ERA5 reanalysis dataset, using billions of measurements from satellites, ships, aircraft and weather stations around the world.
Global Temperatures
- March 2025 was the second-warmest March globally, with an average ERA5 surface air temperature of 14.06°C, 0.65°C above the 1991-2020 average and 1.60°C above the pre-industrial level for March.
- March 2025 was 0.08°C cooler than the record March of 2024, and only marginally warmer — by 0.02°C — than the third warmest March, in 2016.
- March 2025 was the 20th month in the last 21 months for which the global-average surface air temperature was more than 1.5°C above the pre-industrial level. *
- The 12-month period of April 2024 – March 2025 was 0.71°C above the 1991-2020 average, and 1.59°C above the pre-industrial level.
*Datasets other than ERA5 may not confirm the 20 months above 1.5°C highlighted here, due to the relatively small margins above 1.5°C of ERA5 global temperatures observed for several months and differences among the various datasets.
Monthly global surface air temperature anomalies (°C) relative to 1850–1900 from January 1940 to March 2025, plotted as time series for each year. 2025 is shown with a dark red line, 2024 with a dark orange line, 2023 with a yellow line, and 2016 with a light orange line. All other years are shown with thin grey lines. Data source: ERA5. Credit: Copernicus Climate Change Service /ECMWF.
Daily Arctic sea ice extent from October 1978 to 1 April 2025. The year 2025 is shown with a dark blue line, 2024 with a teal line, and 2012 (year of the lowest daily sea ice extent) with a salmon line. Data source: EUMETSAT OSI SAF Sea Ice Index v2.2. Credit: C3S/ECMWF/EUMETSAT.
More information about climate variables in March and climate updates of previous months as well as high-resolution graphics can be downloaded here.
Other useful links:
Answers to frequently asked questions regarding temperature monitoring can be found here.
Follow near-real-time data for the globe on Climate Pulse here.
More on trends and projections on Climate Atlas here.
Access key datasets easily with the new tool ERA Explorer App here.
Temperature and hydrological maps and data are from ECMWF Copernicus Climate Change Service’s ERA5 and ERA5-Land (surface soil moisture) datasets. The findings about global sea surface temperatures (SSTs) presented here are based on SST data from ERA5 averaged over the 60°S–60°N domain. Note that ERA5 SSTs are estimates of the ocean temperature at about 10m depth (known as foundation temperature). The results may differ from other SST products providing temperature estimates at different depths. Sea ice maps and data are from a combination of information from ERA5, as well as from the EUMETSAT OSI SAF Sea Ice Index v2.2. Regional area averages quoted here are the following longitude/latitude bounds: Globe, 180W-180E, 90S-90N, over land and ocean surfaces. Europe, 25W-40E, 34N-72N, over land surfaces only.
More information about the data can be found here.
Information on national records and impacts is based on national and regional reports. For details see the respective temperature and hydrological C3S climate bulletin for the month. C3S has followed the recommendation of the World Meteorological Organization (WMO) to use the most recent 30-year period for calculating climatological averages and changed to the reference period of 1991-2020 for its C3S Climate Bulletins covering January 2021 onward. Figures and graphics for both the new and previous period (1981-2010) are provided for transparency.
More information on the reference period used can be found here.
Copernicus is the Earth observation component of the European Union’s Space programme, looking at our planet and its environment to benefit all European citizens. The programme is coordinated and managed by the European Commission and implemented in partnership with the Member States and European organisations.
The European Centre for Medium-Range Weather Forecasts (ECMWF) is both a research institute and a 24/7 operational service, producing global numerical weather predictions and other data for our Member and Co-operating States and the broader community. It operates a world-class supercomputer facility for weather forecasting and holds one of the largest meteorological data archives.
ECMWF is a key player in Copernicus, the Earth Observation component of the European Union’s Space programme, by implementing quality-assured information on climate change (Copernicus Climate Change Service), atmospheric composition (Copernicus Atmosphere Monitoring Service), and contributing to information on flooding and fire danger (Copernicus Emergency Management Service). Together with ESA and EUMETSAT, ECMWF also delivers the EU’s Destination Earth initiative, which is developing prototype digital twins of the Earth.