ALBANY, N.Y. (Feb. 27, 2025) — Despite being among the warmest years on record, eastern China was hit by an unexpected extreme cold event in December 2023 that caused transportation shutdowns, power supply shortages and agricultural damage.
A new study led by Qian Cheng from the Chinese Academy of Sciences, in collaboration with a team of researchers including Aiguo Dai from the University at Albany, examined the 2023 event to better understand how the warming effect of climate change drives or suppresses these types of extreme cold waves.
Their analysis found that the event could largely be attributed to unusual large-scale atmospheric circulation (wind patterns), which accounted for 83 percent of its intensity. However, they also found that the warming effect of climate change reduced the event's severity by up to 22 percent.
Findings were published in the journal npj Climate and Atmospheric Science.
"Extreme cold events, like the one in China in December 2023, often have major impacts on various sectors of our society," said Dai, a Distinguished Professor in UAlbany's Department of Atmospheric and Environmental Sciences . "Understanding how these events may change due to climate change can help us to stay better informed and prepared for the future. It also gives us more insight into how these events occur under a warming climate."
To reach their analysis, the researchers used a combination of historical weather data and climate simulations to estimate how atmospheric circulation and global warming contributed to the 2023 cold event.
Using similar techniques, they also found that the likelihood and intensity of similar cold events has already dropped by over 92 percent and 1.9 degrees Celsius, respectively, compared to a world without the current global warming trends. They are projected to become even rarer and milder by the end of the century—decreasing in frequency by 95 percent and more than 2 degrees Celsius.
Dai cautions that these cold events will not disappear entirely and that we should be prepared for how climate change impacts extreme weather in other ways, such as more frequent wildfires, droughts and severe storms.
"Studies have shown that while the overall global temperature is rising due to climate change, extreme cold events can still occur and may even become more frequent in certain regions due to the rapid warming of the Arctic," Dai said. "Global warming also has many other adverse effects besides its impact on cold events. These findings are a good first step to better understanding how the warming climate impacts weather patterns. We plan to continue our analysis for other types of extreme events."
Dai is among the most cited scientists in his field with more than 200 published journal articles related to climate science. Among his other recent research includes a 2024 study that linked Arctic sea ice loss to the intensity of El Niño events.
