Monday broke Sunday's record for hottest ever day on Earth

Monday was recorded as the hottest day ever globally, beating a record set the day before, as countries around the world from Japan to Bolivia to the United States continue to feel the heat, according to the European climate change service.

Provisional satellite data published by Copernicus on Wednesday showed that Monday broke the previous day's record by 0.06 degrees Celsius (0.1 degree Fahrenheit).

Climate scientists say it's plausible that this is the warmest it has been in 120,000 years because of human-caused climate change. While scientists cannot be certain that Monday was the very hottest day throughout that period, average temperatures have not been this high since long before humans developed agriculture.

But it's a difficult determination to make, said University of Pennsylvania climate scientist Michael Mann, because data from tree-rings, corals and ice cores don't go that far back globally.

The temperature rise in recent decades is in line with what climate scientists projected would happen if humans kept burning fossil fuels at an increasing rate.

“We are in an age where weather and climate records are frequently stretched beyond our tolerance levels, resulting in insurmountable loss of lives and livelihoods,” Roxy Mathew Koll, a climate scientist at the Indian Institute of Tropical Meteorology.

“Deaths from high temperatures show how catastrophic it is not to take stronger action on cutting CO2,” which is the main heat-trapping gas, Cornell University climate scientist Natalie Mahowald said in an email.

Copernicus’ preliminary data shows the global average temperature Monday was 17.15 degrees Celsius (62.87 degrees Fahrenheit). The previous record before this week was set just a year ago. Before last year, the previous recorded hottest day was in 2016 when average temperatures were at 16.8 degrees Celsius (62.24 degrees Fahrenheit).

While 2024 has been extremely warm, what kicked this week into new territory was a warmer-than-usual Antarctic winter, according to Copernicus. The same thing happened on the southern continent last year when the record was set in early July.

Copernicus records go back to 1940, but other global measurements by the United States and United Kingdom governments go back even further, to 1880. Many scientists, taking those into consideration along with tree rings and ice cores, say last year’s record highs were the hottest the planet has been in about 120,000 years. Now the first six months of 2024 have broken even those.

Without human-caused climate change, scientists say that extreme temperature records would not be broken nearly as frequently as is happening in recent years.

Former head of U.N. climate negotiations Christiana Figueres said “we all scorch and fry” if the world doesn't immediately change course, “but targeted national policies have to enable that transformation.”

Scientists said it was “extraordinary” that such warm days have now occurred in two consecutive years especially when the natural El Nino warming of the central Pacific Ocean ended earlier this year. “This is yet another illustration of just how much the Earth’s climate has warmed,” said Daniel Swain, a climate scientist with the University of California, Los Angeles.