“It’s surprisingly bananas.”
“Unknown territory”.
“The writing is clear on the wall.”
Climate scientists say last month was almost unbelievable, as it broke the record for the hottest September on record by a wide margin.
The September milestone, reported in new data released late Wednesday by the European Union’s Copernicus Climate Change Agency, added to an alarming period of record-breaking temperatures around the world. In June, July and August, the planet experienced its hottest summer on record by a wide margin.
September temperatures are even more surprising to climate scientists.
“In my professional opinion as a climate scientist, this month has been absolutely shockingly bananas,” Zeke Hausfather, head of climate research at financial services firm Stripe, said Tuesday on the platform formerly known as Twitter. I wrote to X.
Samantha Burgess, deputy director of the Copernicus Climate Change Service, said it was worrying to see so many new records being set, but it was even more worrying to see by what margins they were being broken. He said it was true. Average surface temperatures last month were about 1 degree Fahrenheit warmer than September 2020, the warmest September on record.
“Normally records are broken by hundredths of a degree, so this is a really huge amount,” she said.
According to the Copernicus Climate Change Agency, September was also the most unusually warm month on record, meaning the deviation from the average was greater than in any previous month.
The warmth continues into October. Almost two full weeks into fall, temperatures continue to rise around the world this week, with residents of the upper Midwest and Northeast experiencing summer-like weather again this week.
Record-breaking temperatures (over 90 degrees Fahrenheit in some places) have brought unseasonably warm temperatures to vast swaths of the country, with cities from the Great Lakes to the Northeast experiencing high temperatures 10 to 30 degrees above average.
However, the U.S. was not the only country experiencing severe temperature fluctuations. An October heatwave is scorching Western Europe, with temperatures well above 90 degrees Fahrenheit in parts of France and Spain. And in the Southern Hemisphere, unseasonably warm temperatures have been recorded in South America and Australia, all on the heels of multiple heatwaves over the past month during what should have been the winter season in that part of the world. This is what happened.
Climate scientists are perplexed by this dizzying warming trend.
Kim Cobb, director of the Institute at Brown University, said: “We are learning more about what ‘extreme’ means today and how frightening that word can be when our baselines are changing so rapidly. I have to find a new understanding within myself about whether something should continue to be a thing.” He majored in environment and society at Brown University.
For researchers who pay close attention to extreme events like Cobb, 2023 is already an extreme event.
With warmer-than-normal weather month after month, 2023 is on track to become the hottest year on record, surpassing the previous record set in 2016.
“It looks like a virtual lock,” Cobb said of the controversial honor.
This trajectory of global warming has been predicted by climate models, but the pace of change has surprised many scientists.
“Most, if not all, climate scientists felt that the next two years were going to be pretty warm, but I think everyone was a little surprised by how warm it was globally.” said climate scientist Zachary Love. Princeton University.
The warm conditions both this year and in 2016 were driven by El Niño, a natural weather pattern characterized by warmer-than-normal waters in the central and eastern tropical Pacific Ocean. El Niño can affect weather conditions around the world, and the phenomenon typically exacerbates the background warming caused by anthropogenic climate change.
In a warming world, Cobb says, this means El Niño events are more likely to “push temperatures ever further into uncharted territory.”
El Niño conditions are expected to continue until 2024. That means more records will be broken next year, but it’s too early to make reliable predictions of that nature, Burgess said. Still, this year’s events, including devastating floods on multiple continents, weeks of unrelenting heat waves, and the most devastating wildfires ever seen, present a worrying outlook.
“I’m very nervous about what’s going to happen,” Burgess said.
Burgess and colleagues said the current situation should be a wake-up call to policymakers about the need to take immediate action to avoid the most devastating consequences of climate change.
Cobb said conditions and temperatures will likely change over the next few years, but the enormous impact of human-induced global warming cannot be ignored.
“The writing is clearly on the wall,” she said. “We’ve kept our foot on the gas on emissions, and we’re basically unable to keep up with the changes that are happening, let alone the continued warming and extreme impacts that we know are happening. Pike.”