Last year was the fifth warmest on record, with global land and ocean temperatures about 1.1C warmer than during the pre-industrial era, according to the US’s top climate scientists.
The data, from the National Oceanic and Atmospheric Administration (NOAA) and the National Aeronautics and Space Administration (Nasa), come days after similar findings from the EU’s earth observation programme, Copernicus, which also ranked 2022 as the fifth warmest year, and said temperatures had been about 1.2C higher than before human-driven warming set in.
A fourth group, the Geneva-based World Meteorological Organisation, reached a strikingly similar conclusion, estimating that the average global temperature in 2022 was about 1.2C above pre-industrial levels.
The data are “pretty alarming”, said Nasa’s administrator Bill Nelson. “Science leaves no room for doubt,” he added. “What we’re seeing is our warming climate [. . .] it’s a warning all of us.”
“If our leaders [. . . ] do not act on this scientific data, our ice sheets are going to continue to melt, our oceans will become more acidic, extreme weather will intensify [. . .] This is a call for action.”
Last year brought a series of devastating extreme weather events to countries around the world, from floods to wildfires and droughts. Scientists are clear that such events will become more common and intense with every fraction of a degree of warming.
Under the Paris climate accord signed in 2016, almost 200 nations pledged to strive to limit warming to 1.5C. But the WMO said on Thursday that the “likelihood of — temporarily — breaching the 1.5C limit of the Paris Agreement is increasing with time”.
According to NOAA, the 2022 annual Antarctic sea ice extent was at a near-record low, second only to 1987, and the 10-warmest years on record have all occurred since 2010.
The group found that Europe and Asia had their second warmest years, behind 2020, while Copernicus concluded that 2022 had been Europe’s hottest summer on record. NOAA’s analysis of global surface temperatures ranked last year as the sixth warmest year.
The unusual heat last year occurred despite the “temperature-suppressing” presence of the La Niña phenomenon. La Niña involves the large-scale cooling of the Pacific Ocean’s surface, and has persisted for three consecutive years.
“Even those years with a temporary cooling influence from La Niña, such as 2022, are now much warmer than all years before 2015,” the UK’s Met Office said. 2022 was the ninth successive year to have “equalled or exceeded 1C above the pre-industrial period”, the group said.
However, both Copernicus and NOAA said this week that the chances of a fourth La Niña year were waning. Instead, the chances of an occurrence of the opposing phenomenon, El Niño, which has a warming effect, had increased, said Michelle L’Heureux, a scientist at the US National Weather Service’s Climate Prediction Center.
There was roughly a “50 per cent chance” of El Niño occurring later this year, she said. However, similar indications were present at the beginning of the last few years, “so that does give us pause,” she added. “I would not be shocked to even see a return of La Niña.”
One of the last significant El Niño events was in 2016. Meteorological agencies said that year was the warmest on record, raising concerns that the phenomenon’s return could fuel one of the hottest ever years in 2023.
