July 2023 was likely the hottest month in 120,000 years

Scientists are already calculating that July 2023 will be the hottest month on record—and likely the warmest month that humanity has ever experienced. The United Nations’ World Meteorological Organization (WMO) and the European Union’s Copernicus Climate Change Service announced late last week that this month’s heat was beyond record-smashing. The planet’s temperature, they report, has been temporarily passing over the crucial threshold of limiting global warming to 2.7 degrees Fahrenheit (1.5 degrees Celsius) above pre-industrial temperatures.

[Related: Extreme heat warning extends to more than 100 million people in the US.]

This news comes as no surprise to the millions of people around the world facing extreme heat. Phoenix, Arizona is about to enter its 31st straight day of temperatures above 110 degrees. Parts of northwest China saw a record-breaking 126 degrees earlier this month, while southern Europe is seeing wildfires following an extreme heatwave. These global heat waves would be “virtually impossible” without climate change, according to an early analysis released last week by the World Weather Attribution initiative.

“We can say that the first three weeks of July have been the warmest three week periods ever observed in our record,” Carlo Buentempo, director of the Copernicus Climate Change Service, said via Zoom and in a statement. “This anomaly is so large with respect to other record-breaking months in our record that we are virtually certain that the month, the month as a whole, will become the warmest July on record, the warmest month on record, in all likelihood.”

Records like these generally track average air temperature across the entire world and are broken by hundredths of a degrees. However, the temperature for July’s first 23 days averaged 62.51 degrees, higher than the 61.93 degrees set in July 2019, according to the UN’s report. The data for these records goes back to 1940, but many scientists believe that it is almost certain that these recent readings are the warmest the Earth has been in 120,000 years, based on the data collected from coral reefs, deep sea sediment cores, and tree rings that paint a picture of past climates. 

Buontempo and other scientists believe that the steamy weather can be attributed to a combination of human-caused climate change and this year’s natural El Niño warming pattern in parts of the central Pacific. This pattern changes weather around the world and follows three straight years of La Niña, a Pacific cooling pattern. Despite multiple La Niña cooling patterns, 2015 to 2022 saw eight of the warmest years on record based on a 173 year long dataset. WMO’s Director of Climate Services Chris Hewitt cited “a clear and dramatic warming decade on decade” since the 1970s. 

[Related: World set to ‘temporarily’ breach major climate threshold in next five years.]

“But now the La Niña has ended” – to be replaced by the sea-warming El Niño effect – waters have begun to heat up in the tropical Pacific, bringing the “almost certain likelihood that one of the next five years will be the warmest on record,” Hewitt said in a statement. 

In May, WMO scientists predicted that the world will likely temporarily exceed the 2.7 degree threshold for at least one of the next five years. 

Temperatures in the Atlantic Ocean have also been skyrocketing since the spring. In mid-May, the global ocean surface temperatures reached “unprecedented levels” for the time of year and the ocean temperatures off the coast of Florida reached 100 degrees in some locations. 

UN Secretary-General António Guterres underscored the need for global action to reduce  emissions, climate adaptations, and climate finance. He warned that “the era of global warming has ended” and “the era of global boiling has arrived.”

“We can still stop the worst,” said Guterres. “But to do so we must turn a year of burning heat into a year of burning ambition.”