SCOTT SIMON, HOST:
After a summer of extreme heat around the world, the U.S. government says September was the hottest in its 174 years of climate records. Researchers say there is a clear link between this heat and human-caused climate change, as NPR's Julia Simon reports.
JULIA SIMON, BYLINE: It's not just that last month was the hottest September on record, according to the National Oceanic and Atmospheric Administration, or NOAA. It's how abnormally hot it was.
ELLEN BARTOW-GILLIES: It also beat out the previous record September by 0.83 degrees Fahrenheit, which is a pretty significant jump.
J SIMON: That's NOAA climatologist Ellen Bartow-Gillies, the lead author of the report. She said another way to think about it, compared to the average July temperature from 2001 to 2010...
BARTOW-GILLIES: September 2023 was actually warmer than that.
J SIMON: There are two major factors driving this jump in average global temperatures. Bartow-Gillies says the big one is climate change, which is mostly caused by humans burning fossil fuels. And there's El Nino that periodically warms parts of the Pacific Ocean and affects weather patterns worldwide.
BARTOW-GILLIES: What it boils down to is that these conditions magnify the existing warmth.
J SIMON: As for what this hot September meant, Bartow-Gillies says this heat affected people all over the world, even in places in the Southern Hemisphere that were coming out of winter, not summer. The report found North America, South America, Europe and Africa had their warmest Septembers on record. Antarctica also saw its warmest September, which contributed to record-low sea ice. NOAA also found that ocean surface temperatures were really high. That warmer water helped fuel wetter, more intense storms from New York City to Libya, where dam failures caused thousands of deaths. Ultimately, these numbers shocked lots of people, even climate scientists.
BERNADETTE WOODS PLACKY: Geez. These numbers. Whew.
J SIMON: We sent the report to Bernadette Woods Placky, chief meteorologist at Climate Central, who wasn't involved in the research. She says it's yet another wake-up call.
WOODS PLACKY: A report like this really screams the urgency for advancing our climate actions, doing it quicker and scaling it bigger.
J SIMON: Woods Placky says some climate solutions that can help reduce planet-heating fossil fuels include shifting to renewable energy, electrifying transport and changing how we manage land.
Julia Simon, NPR News. Transcript provided by NPR, Copyright NPR.
NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.