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Surface air temperature anomaly for May 2023 relative to the May average for the period 1991-2020. Data source: ERA5. Credit: Copernicus Climate Change Service/ECMWF.
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 temperature, sea ice cover and hydrological variables. All the reported findings are based on computer-generated analyses using billions of measurements from satellites, ships, aircraft and weather stations around the world.
May 2023 – temperature highlights:
- The month was the joint second warmest May globally, less than 0.1°C cooler than the warmest May on record.
- Sea surface temperature and marine air temperature averaged over all ice-free seas were the highest on record for May.
- Temperatures on average were close to normal over most of Europe.
- Parts of Canada, Africa and South-East Asia were significantly warmer than normal.
- It was notably cooler than normal over Australia and from North-West India to southern Siberia.
- An El Niño signal continued to emerge over the tropical eastern Pacific.
According to Samantha Burgess, Deputy Director of C3S, “May 2023 was the 2nd warmest globally as we are seeing the El Niño signal continuing to emerge in the equatorial Pacific. Temperatures over the ocean are already reaching record levels and our data indicates that the average temperature over all ice-free seas for May 2023 was higher than for any other May.”
Temperatures (°C) averaged over ice-free seas for the month of May from 1979 to 2023. Light blue bars denote sea surface temperature and dark blue bars denote marine air temperature shifted by 1°C. Data source: ERA5. Credit: Copernicus Climate Change Service/ECMWF.
May 2023 – hydrological variables highlights:
- In May 2023, it was wetter than average over most of southern Europe and in the west of Iceland; heavy precipitation led to floods in Italy and the western Balkans.
- Drier-than-average conditions were recorded over most of the Iberian Peninsula, over Denmark, the Baltic Countries, southern Scandinavia and much of western Russia.
- Beyond Europe, in May 2023 it was drier than average over large regions of North America, central Russia, in East and southeast Asia, the Horn of Africa, most of southern Africa, Australia and South America.
- Wetter than average regions included south-eastern and south-western North America, south-eastern Africa, southern Brazil, Pakistan and New Zealand.
Anomalies in precipitation, the relative humidity of surface air, the volumetric moisture content of the top 7 cm of soil and surface air temperature for May 2023 with respect to May averages for the period 1991-2020. The darker grey shading denotes where soil moisture is not shown due to ice cover or climatologically low precipitation. Data source: ERA5 Credit: Copernicus Climate Change Service/ECMWF
May 2023 – Sea ice highlights:
- For the third time in 2023, Antarctic sea ice extent reached a record low monthly value for the time of year within the satellite data record, at 17% below average.
- Sea ice concentrations were most below-average in the Weddell, Bellingshausen, and northern Ross Seas while above-average concentrations continued to prevail in the Amundsen Sea.
- Arctic sea ice extent was very close to average and almost identical to the value recorded in May 2022.
- Sea ice concentration anomalies were dominated by above-average concentrations in the Greenland Sea and below-average concentrations in the Barents Sea.
Time series of monthly mean Antarctic sea ice extent anomalies for all May months from 1979 to 2023. The anomalies are expressed as a percentage of the May average for the period 1991-2020. Data source: EUMETSAT OSI SAF Sea Ice Index v2.1. Credit: Copernicus Climate Change Service/ECMWF/EUMETSAT.
Boreal Spring 2023 – Seasonal highlights:
- In boreal spring 2023, it was drier than average over the Iberian Peninsula, and most of eastern Europe. Conditions were wetter than average over Iceland, Ireland, most of the UK, Italy, most of central and southeastern Europe.
- Beyond Europe, boreal spring was wetter than average in the western and southeastern USA, over parts of the Horn of Africa, the Arabian Peninsula and regions of central Asia, northern Australia and western southern Africa. The rest of North America, most of South America as well as much of southern Africa experienced drier-than-average conditions.
Anomalies in precipitation, the relative humidity of surface air, the volumetric moisture content of the top 7 cm of soil and surface air temperature for Spring 2023 with respect to Spring averages for the period 1991-2020. The darker grey shading denotes where soil moisture is not shown due to ice cover or climatologically low precipitation. Data source: ERA5 Credit: Copernicus Climate Change Service/ECMWF
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Video material accompanying the maps can be found here.
More information about climate variables in May and climate updates of previous months as well as high-resolution graphics and the video can be downloaded here.
Answers to frequently asked questions regarding temperature monitoring can be found here.
Information about the C3S data set and how it is compiled.
Temperature and hydrological maps and data are from ECMWF Copernicus Climate Change Service’s ERA5 dataset.
Sea ice maps and data are from a combination of information from ERA5, as well as from the EUMETSAT OSI SAF Sea Ice Index v2.1, Sea Ice Concentration CDR/ICDR v2 and fast-track data provided upon request by OSI SAF.
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 can be found here.
Information on national records and impacts
Information on national records and impacts are 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.
About Copernicus and ECMWF
Copernicus is a component of the European Union’s space programme, with funding by the EU, and is its flagship Earth observation programme, which operates through six thematic services: Atmosphere, Marine, Land, Climate Change, Security and Emergency. It delivers freely accessible operational data and services providing users with reliable and up-to-date information related to our planet and its environment. The programme is coordinated and managed by the European Commission and implemented in partnership with the Member States, the European Space Agency (ESA), the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), the European Centre for Medium-Range Weather Forecasts (ECMWF), EU Agencies and Mercator Océan, amongst others.
ECMWF operates two services from the EU’s Copernicus Earth observation programme: the Copernicus Atmosphere Monitoring Service (CAMS) and the Copernicus Climate Change Service (C3S). They also contribute to the Copernicus Emergency Management Service (CEMS), which is implemented by the EU Joint Research Council (JRC). The European Centre for Medium-Range Weather Forecasts (ECMWF) is an independent intergovernmental organisation supported by 35 states. It is both a research institute and a 24/7 operational service, producing and disseminating numerical weather predictions to its Member States. This data is fully available to the national meteorological services in the Member States. The supercomputer facility (and associated data archive) at ECMWF is one of the largest of its type in Europe and Member States can use 25% of its capacity for their own purposes.
ECMWF has expanded its location across its Member States for some activities. In addition to an HQ in the UK and Computing Centre in Italy, offices with a focus on activities conducted in partnership with the EU, such as Copernicus, are in Bonn, Germany.
The Copernicus Atmosphere Monitoring Service website can be found at http://atmosphere.copernicus.eu/
The Copernicus Climate Change Service website can be found at https://climate.copernicus.eu/
More information on Copernicus: www.copernicus.eu
The ECMWF website can be found at https://www.ecmwf.int/
Twitter:
@CopernicusECMWF
@CopernicusEU
@ECMWF
