The last three days were quite likely the hottest in Earth’s modern history, scientists said, as an astonishing surge of heat across the planet continued to shatter temperature records from North America to Antarctica.
The spike comes as forecasters warn that the Earth is entering a multiyear period of exceptional warmth driven by two main factors: humans continuing to burn oil, gas and coal alongside the return of El Niño, a cyclical weather pattern, after three years.
Already, the surge has been drastic. The planet just experienced its warmest June ever recorded, European researchers said, with deadly heat waves in Texas, Mexico and India. In the North Atlantic, ocean temperatures were 2.9 degrees Fahrenheit hotter in May than they typically are at that time of year. Around Antarctica, sea ice levels have plunged to record lows.
And the heat shows no signs of letting up. On Monday, global average temperatures reached 62.6 degrees Fahrenheit, or 17 degrees Celsius, the hottest day ever recorded, according to the University of Maine’s Climate Reanalyzer, which combines satellite data, observations and computer modeling to provide a real-time update of climate conditions.
But that record was shattered the following day. On Tuesday, global average temperatures rose to a new high of 62.9 degrees Fahrenheit.
A separate analysis by the European Union’s Copernicus Climate Change Service confirmed that Tuesday was the hottest day Earth has experienced since at least 1940, when records began, and very likely before that.
The overall warming of the planet is “well within the realm of what scientists had projected would happen” as humans continued to pump heat-trapping greenhouse gases into the atmosphere, said Zeke Hausfather, a climate scientist at Berkeley Earth and the payments company Stripe.
But, he added, there may be other factors layered on top of human-caused warming that have helped drive temperatures up so dramatically in recent months. For instance, a cyclical phenomenon in the Pacific Ocean known as the El Niño-Southern Oscillation causes year-to-year fluctuations by shifting heat in and out of deeper ocean layers. Global surface temperatures tend to be somewhat cooler during La Niña years and somewhat hotter during El Niño years.
“A big reason we’re seeing so many records shattered is that we’re transitioning out of an unusually long three-year La Niña, which suppressed temperatures a bit, and into a strong El Niño,” Dr. Hausfather said.
Other dynamics may be in play, too. In January 2022, a volcanic eruption beneath the Pacific archipelago nation of Tonga blasted a huge amount of vaporized seawater into the atmosphere that could be trapping additional heat. Some scientists have also suggested that efforts to clean up sulfur pollution from ships and coal plants around the world might push up temperatures slightly, since sulfur dioxide in the atmosphere tends to have a slight cooling effect. But scientists have yet to definitively untangle its role in the current heat surge.