As weather extremes become more frequent and climate change worsens, 15 national heat records have been broken since the beginning of the year, an influential climate historian told the Guardian.

In addition, according to Maximiliano Herrera, who maintains an archive of extreme weather events, 130 more monthly temperature records were broken at the national level and tens of thousands of local maximum temperatures were recorded at monitoring stations from the Arctic to the South Pacific.

He said the unprecedented number of records in the first six months was astonishing. “This amount of extreme heat events exceeds anything ever seen before or thought possible,” he said. “The months from February 2024 to July 2024 were the most record-breaking in every statistic.”

This is alarming because last year’s extreme heat was largely due to a combination of human-induced global warming – caused by the burning of gas, oil, coal and trees – and a natural El Niño phenomenon, a warming of the tropical Pacific surface that is associated with higher temperatures in many parts of the world. The El Niño phenomenon has been waning since February this year, but this has brought little relief.

“With the end of El Niño, the number of records has by no means decreased; in fact, it is now declining even faster than at the end of 2023,” Herrera said.

At the local level, new ground is broken every day. On some days, thousands of monitoring stations record new monthly highs or lows. The latter are particularly harsh because high nighttime temperatures mean people and ecosystems have no time to recover from the relentless heat. In late July, for example, China’s Yueyang region suffered unprecedented lows of 32.0°C and dangerously high humidity during the nighttime hours.

The geographic range of national records is staggering. Mexico reached its highest temperature of 52°C in Tepache on June 20. On the other side of the world, the Australian territory of Cocos Islands reached its all-time high of 32.8°C for the third time this year on April 7.

The greatest heat, however, was in the tropics. On June 7, Egypt recorded a national high of 50.9 degrees Celsius in Aswan. Two days earlier, Chad set its national record at 48 degrees Celsius in Faya. On May 1, Ghana reached a new high of 44.6 degrees Celsius in Navrong, while Laos reached new heat zones with 43.7 degrees Celsius in Tha Ngon. Herrera said the tropics had set records every day for 15 months in a row.

Herrera, a Costa Rican who has been monitoring climate records for 35 years, fills an important gap in global temperature monitoring. Since 2007, international records have been archived by the World Meteorological Organization (WMO), which convenes expert panels to closely examine each individual record, a time-consuming process. At the same time, national and subnational records are updated hourly or daily by a variety of different organizations. Herrera quickly pulls the latter together, cross-checks them with local sources and maintains updates on his account Extreme Temperatures Around the World X.

His findings are consistent with, and often even ahead of, the findings of major institutions that all warn of rapid global warming.

“The sirens are blaring on all major indicators… Some records are not just breaking, they are breaking all records. And the changes are accelerating,” said UN Secretary-General António Guterres about last year’s extreme global heat.

The European Union’s leading monitoring agency, the Copernicus Climate Change Service, recently reported that June was the 13th consecutive month of setting a monthly temperature record: temperatures were 1.5 degrees above the pre-industrial average, leading to more intense heatwaves, extreme rainfall and droughts, a decline in ice sheets, sea ice and glaciers, and accelerated sea level rise and ocean warming.

The WMO also reported that Temperatures above 50 °C have been measured in at least 10 countries so far this year..

There is no end in sight to the unwelcome records, says Carlo Buontempo, the director of Copernicus: “Even if this particular series of extremes ends at some point, we will certainly see new records as the climate continues to warm. This is inevitable if we do not stop releasing greenhouse gases into the atmosphere and oceans.”

Hopes for cooling have so far proved deceptive. Preliminary data from the Copernicus ERA5 satellite suggest that July 22 was the hottest day in Earth’s history, with an average global air temperature of 17.15°C.

Herrera said he hopes severe weather warnings can prepare the world for what’s to come and reduce threats to lives, infrastructure and the economy. “When severe weather occurs, we humans and other species are under stress or at risk, so we’re potentially more vulnerable,” he said.

This year, national and regional weather records were broken or set

February 28 The Cocos Islands reached their highest temperature ever at 32.8 °C. They reached this mark again on February 29 And 7 April

March 6 Costa Rica broke its national record with 41 °C at Cerro Huacalito. The record was beaten again with 41.5 °C at March 23 in the same place

12 March Comoros broke its national record with 36.2 °C at Hahaya Airport

March 13 Congo broke its national record with 39.6 °C in Impfondo

March 24 The Maldives broke their national record with 35.1 °C in Hanimadhoo. They set it again on 11.April

March 31 Togo broke its national record with 44 °C in Mango

3 April Mali broke its national record with 48.5 °C in Kayes

10 April Belize broke its national record with 42.3 °C in Barton Creek. This temperature was later set at 17 May at Chaa Creek

24.April Chad set its national record with 48 °C in Faya. This was set again on 5 June

27.April Cambodia broke its national record with 42.8 °C in Preah Viehar and Svay Leu

May 1st Ghana broke its national record with 44.6 °C in Navrongo

May 1st Laos broke its national record with 43.7 °C in Tha Ngon

29 May Palau set its national record with 35 °C at Babelthuap International Airport. June 2 It exceeded it with 35.6 °C.

7 June Egypt broke its national record with 50.9 °C in Aswan

20 June Mexico has set its national record with 52 °C in Tepache