Continuing the temperature trend from this summer, September 2023 was the hottest September on record, according to scientists at NASA’s Goddard Institute for Space Studies (GISS). The month also set the record for the highest temperature anomaly—the largest difference from the long-term average.

Temperatures advance from January through December rising during warmer months and falling during cooler months. A long-term warming trend can be seen as the height of each month increases over time, the result of human activities releasing greenhouse gases like carbon dioxide into the atmosphere.

“What’s remarkable is that these record values are happening before the peak of the current El Nino event, whereas in 2016 the previous record values happened in the spring, after the peak,” said Gavin Schmidt, director of GISS. El Nino is the warm phase of a naturally recurring pattern of trade winds and ocean temperatures in the Eastern Tropical Pacific that influences global temperatures and precipitation patterns.

- This press release was originally published on the NASA Goddard Space Flight Center website