The last 12 months were the hottest ever measured in a row, according to a new report from the science nonprofit Climate Central.
The report found human activities, primarily the burning of fossil fuels, released carbon dioxide and other greenhouse gases that were the direct cause of the unnatural warming.
In that time, the average global temperature was 1.3 degrees Celsius higher than it was in preindustrial times.
One in four people worldwide suffered dangerous heat waves, and 9 out of 10 people worldwide experienced at least 10 days of high temperatures that climate change made at least three times more likely.
"I think the thing that really came screaming out of the data this year was nobody is safe. Everybody was experiencing unusual climate-driven heat at some point during the year," said Andrew Pershing, a climate scientist at Climate Central.
Hottest September on record follows one hot summer
September 2023 was the fourth month in a row of record-warm global temperatures. It was warmer than the average July from 2001 to 2010.
Researchers say we can expect more of the same, and that the temperature increases we're seeing now are consistent with what the available data has forecast for years.
Heating may become even more intense in the years ahead, they say, because the oceans that have buffered much of the excess heat in the atmosphere are reaching the limits of the heat they can absorb.
The effects of climbing temperatures may not manifest the same way across the planet, however. The increased heat contributes to different extremes of precipitation, drought, sea level rise and wildfires.
