September 2023 set a new mark for hotter-than-normal temperatures on planet Earth, a European climate agency reported Thursday.
The average global temperature in September was 1.7 degrees Fahrenheit (0.93 degrees Celsius) hotter than the average for the month from 1991 through 2020.
That’s the warmest margin above average for any month in 83 years, according to the records kept by the European Space Agency’s Copernicus Climate Change Service.
According to Copernicus, the average temperature around the world for September was 61.48 degrees Fahrenheit (16.38 degrees Celsius) which broke the previous record for September, in 2020, by 0.9 degrees Fahrenheit or a half-degree Celsius.
“It’s just mind-blowing really,” said Copernicus Director Carlo Buontempo. “Never seen anything like that in any month in our records.”
The record-hot September comes on the heels of summer 2023 breaking global heat records for the season. The hottest-ever August on record was the second hottest month ever, following July 2023, according to the World Meteorological Organization (WMO) and Copernicus.
Simultaneous extreme heat waves raging across the U.S. and Europe would be “virtually impossible” if not for climate change, according to analysis from the World Weather Attribution initiative (WWA), an international group of scientists who assess the role of climate change in extreme weather events.
While the WWA’s scientists have conceded that El Niño—a weakening of trade winds that causes northern U.S. and Canada to be dryer and warmer than usual—has been a factor this year, they state that it’s the burning of fossil fuels that has been the main driver of the rising temperatures.
The hot temperatures stretching across the globe have been chiefly driven by persistent and unusual warmth in the world’s oceans, which didn’t cool off as much in September as normal and have been record hot since spring, according to Copernicus’ Buontempo.
“This is not a fancy weather statistic,” warned Imperial College of London climate scientist Friederike Otto. “It’s a death sentence for people and ecosystems. It destroys assets, infrastructure, harvest.”
Heat is the deadliest natural disaster known to humans, killing more every year than other extreme weather events, including flooding, tornadoes, hurricanes or lightning.
Heat was the underlying or contributing cause of about 1,670 deaths in 2022, according to the U.S. Centers for Disease Control and Prevention (CDC).