European heatwave drives world's second-hottest May on record
New monthly records were set during the month, creating what Copernicus described as "particularly difficult" conditions in France, the United Kingdom, Ireland and Portugal.
"In Europe, an unusually early and intense heatwave shows how quickly extreme weather events are becoming the norm rather than the exception," Samantha Burgess, a climatologist at Copernicus, said.
May this year ranked second to the record-breaking month of May 2024 in Copernicus's monthly global climate assessment.
Temperatures likely to remain at record levels until 2030, UN warns
Heat arriving earlier
Combined land and sea temperatures averaged 15.81C worldwide in May – or 1.42C above estimated temperatures during the pre-industrial period of 1850-1900, before large-scale burning of coal, oil and gas began to warm the climate.
Numerous monthly temperature records were broken across Europe during May.
"Although remarkable, this phenomenon is part of the rapid warming of Europe and the long-term trend towards more frequent, more intense and earlier heatwaves," Copernicus said in its assessment.
Exceptionally high water temperatures in parts of the tropical Pacific also put pressure on the climate, the report said.
El Nino threat grows as Europe prepares for another hot summer
El Nino returning
The equatorial Pacific continues to move towards El Nino conditions that are expected in the coming months, Copernicus said.
El Nino is part of a natural cycle in the Pacific Ocean that develops in some years and gradually affects temperatures, winds and weather patterns around the world.
The last El Nino episode took place in 2023-2024.
An 80 percent chance of El Nino developing between June and August was identified in early June by the World Meteorological Organisation.