The data reinforces our understanding that new highs are being set for localised heat at an alarming rate, while ‘coldest days’ are becoming more difficult to find.
According to the National Centers for Environmental Information at the National Oceanic and Atmospheric Administration, mean monthly temperature records last reached new highs in September 2023, when 20% of the Earth’s surface had never been hotter, and April and June 2024, when 14% of our surface set new precedents. This has now been followed by May 2025, with 7% of total land and sea surface hitting never-before-seen highs.
By comparison, January 2024 was the most severe month for setting new cold snap mean temperatures, but just 0.9% of the Earth experienced this phenomenon. This reflects an emerging trend in which the coldest of the cold days are becoming less common compared to the hottest of the hot. Analysis of historic figures show that this has become the norm since the Millennium, whereas it was much more likely that cold records would be broken during the 1950s, 60s and 70s.
Chart: Statista
NASA backs this up, with the US space agency confirming last year its observations showed ‘unequivocal evidence that Earth is warming at an unprecedented rate.’ And across the Atlantic, the European Space Agency’s Copernicus programme clocked the hottest daily global average temperature since its records began back in 1940, with the world hitting 17.16C on 22nd July 2024.
In the preceding two years, 36 countries broke all-time national heat records, with a number achieving this more than once. South East Asia was particularly badly impacted, with Cambodia reaching 42.8C and Laos 43.7C – neither of which had dealt with those temperatures before.
Chart: Statista
Meanwhile, 2022 was another big year for record temperatures, with the UK topping 40C for the first time in history, and Australia and Uruguay matching previous all-time-highs, respectively 50.7C and 44C. 12 months earlier Italy set the all-time-record for Europe, with 48.8C, with Canada and Spain also reaching new high temperatures. However, these still fail to top the historic worldwide high of 56.7C in Furnace Creek, Death Valley National Park, USA, recorded in 1913.
Image: Rapha Wilde / Unsplash
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