Driven by human-caused climate change and boosted by El Nio weather event, official data released on Tuesday showed 2023 remained the hottest year on record.
2023 was 0.60C warmer than the 1991-2020 average and 1.48C warmer than the 1850-1900 pre-industrial level
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, which released the data, monitored several key climate indicators throughout the year, reporting on record-breaking conditions such as the hottest month on record and daily global temperature averages briefly surpassing pre-industrial levels by more than 2C.
Unprecedented global temperatures from June onwards led 2023 to become the warmest year on record overtaking by a large margin 2016, the previous warmest year, read the statement issued by the Copernicus Climate Change Service.
The 2023 Global Climate Highlights report based mainly on the ERA5 reanalysis dataset presents a general summary of 2023s most relevant climate extremes and the main drivers behind them, such as greenhouse gas concentrations, El Nio and other natural variations.
Mauro Facchini, Head of Earth Observation at the Directorate General for Defence Industry and Space, European Commission, comments: We knew thanks to the work of the Copernicus programme throughout 2023 that we would not receive good news today. But the annual data presented here provides yet more evidence of the increasing impacts of climate change. The European Union, in line with the best available science, has agreed on an emission reduction of 55% by 2030 now just 6 years away. The challenge is clear.
Samantha Burgess, Deputy Director of the Copernicus Climate Change Service: 2023 was an exceptional year with climate records tumbling like dominoes. Not only is 2023 the warmest year on record, it is also the first year with all days over 1C warmer than the pre-industrial period. Temperatures during 2023 likely exceed those of any period in at least the last 100,000 years.
Global surface air temperature highlights
2023 is confirmed as the warmest calendar year in global temperature data records going back to 1850.
2023 had a global average temperature of 14.98C, 0.17C higher than the previous highest annual value in 2016.
2023 was 0.60C warmer than the 1991-2020 average and 1.48C warmer than the 1850-1900 pre-industrial level.
It is likely that a 12-month period ending in January or February 2024 will exceed 1.5C above the pre-industrial level.
2023 marks the first time on record that every day within a year has exceeded 1C above the 1850-1900 pre-industrial level. Close to 50% of days were more than 1.5C warmer then the 1850-1900 level, and two days in November were, for the first time, more than 2C warmer.
Annual average air temperatures were the warmest on record, or close to the warmest, over sizeable parts of all ocean basins and all continents except Australia.
Each month from June to December in 2023 was warmer than the corresponding month in any previous year.
July and August 2023 were the warmest two months on record. Boreal summer (June-August) was also the warmest season on record.
September 2023 was the month with a temperature deviation above the 19912020 average larger than any month in the ERA5 dataset.
December 2023 was the warmest December on record globally, with an average temperature of 13.51C, 0.85C above the 1991-2020 average and 1.78C above the 1850-1900 level for the month. You can access information specific for December 2023 in our monthly bulletin.
Ocean surface temperature highlights
Global average sea surface temperatures (SSTs) remained persistently and unusually high, reaching record levels for the time of year from April through December
2023 saw a transition to El Nio. In spring 2023, La Nia came to an end and El Nio conditions began to develop, with the WMO declaring the onset of El Nio in early July.
High SSTs in most ocean basins, and in particular in the North Atlantic, played an important role in the record-breaking global SSTs
The unprecedented SSTs were associated with marine heatwaves around the globe, including in parts of the Mediterranean, Gulf of Mexico and the Caribbean, Indian Ocean and North Pacific, and much of the North Atlantic
European temperature highlights
2023 was the second-warmest year for Europe, at 1.02C above the 1991-2020 average, 0.17C cooler than 2020, the warmest year on record.
Temperatures in Europe were above average for 11 months during 2023 and September was the warmest September on record.
European winter (December 2022 February 2023) was the second-warmest winter on record.
The average temperature for the European summer (June-August) was 19.63C; at 0.83C above average, it was the fifth-warmest on record.
European autumn (September-November) had an average temperature of 10.96C, which is 1.43C above average. This made autumn the second-warmest on record, just 0.03C cooler than autumn 2020.
Other remarkable highlights
2023 was remarkable for Antarctic sea ice: it reached record low extents for the corresponding time of the year in 8 months. Both the daily and monthly extents reached all-time minima in February 2023.
Arctic sea ice extent at its annual peak in March ranked amongst the four lowest for the time of the year in the satellite record. The annual minimum in September was the sixth-lowest.
The atmospheric concentrations of carbon dioxide and methane continued to increase and reached record levels in 2023, reaching 419 ppm and 1902 ppb respectively. Carbon dioxide concentrations in 2023 were 2.4 ppm higher than in 2022 and methane concentrations increased by 11 ppb.
A large number of extreme events were recorded across the globe, including heatwaves, floods, droughts and wildfires. Estimated global wildfire carbon emissions in 2023 increased by 30% with respect to 2022 driven largely by persistent wildfires in Canada.
