The year 2024 is almost certain to set a new record as the warmest year in documented history, according to the European Union’s Copernicus Climate Change Service (C3S). Analysing data up through October, C3S found this year’s temperatures are set to surpass previous records that date back to 1940.

October’s global average temperature rose to 1.65 degrees Celsius above pre-industrial levels, marking the 15th of the past 16 months in which temperatures exceeded the 1.5-degree Celsius threshold outlined in the Paris Agreement, C3S reported. This threshold is a key marker, as temperatures above this level are likely to drive more severe and unpredictable impacts of climate change.

"After 10 months, 2024 is now virtually certain to become the warmest year on record and the first to exceed 1.5 degrees Celsius above pre-industrial levels,” Samantha Burgess, deputy director of C3S, said on November 7, citing the ERA5 dataset. This milestone, Burgess added, should prompt urgent action at the upcoming COP29 Climate Change Conference.

The ERA5 dataset reanalyses hourly meteorological conditions dating to 1979. Projections from this dataset indicate that the average global temperature for 2024 will likely surpass 1.55 degrees Celsius, up from 1.48 degrees in 2023. C3S noted that for 2024 not to become warmer than 2023, an unprecedented drop in temperatures to almost zero would be needed for the rest of the year.

In Europe, October registered as the fifth-warmest on record, with average surface temperatures of 10.83 degrees Celsius, which is 1.23 degrees above the October norm for 1991-2022. The warmest October in Europe was recorded in 2022, with temperatures 1.92 degrees above average.

Europe experienced severe flooding in multiple regions during October, which scientists linked to intensified rainfall driven by climate change. On October 29, extreme rainfall caused devastating floods in Valencia, eastern Spain, claiming more than 200 lives. Italy’s Emilia-Romagna region was also hit hard by flooding starting October 16.

Other parts of northern and western Europe, including the Iberian Peninsula, France, northern Italy, Norway, northern Sweden and areas east of the Black Sea, saw significant rainfall as well, according to C3S.

Elsewhere, wetter-than-average conditions were observed in southern and eastern China and Taiwan, where Tropical Storm Kong-rey brought heavy rain at the end of the month. In the United States, Hurricane Milton caused major flooding in Florida, fuelled by a combination of heavy rain and storm surges.

In contrast, exceptionally dry conditions persisted in parts of the United States, Australia’s central lowlands, southern Africa, Madagascar, Argentina and Chile, where a severe drought continues.

The extent of Antarctic sea ice remains near historic lows. In October 2024, the average sea ice extent was 17.1mn square kilometres, 8% below the 1991-2020 average for October and the second-lowest extent on record for this month, after the record low of -11% in October 2023. This trend of minimal sea ice coverage has persisted since early 2023.

Parts of the South Atlantic, Indian Ocean, and northern Ross Sea regions saw particularly low sea ice concentrations up to the end of October. In the Arctic, the sea ice extent in October was 19% below the 1991–2020 average, marking the fourth-lowest extent in the satellite data record. By October 31, Arctic sea ice coverage was only 8mn square kilometres, the third-lowest level recorded for that time of year, following 2016 and 2020.