Despite 2023 and 2024 ranking as the warmest years on record, extreme cold events still gripped parts of China, Europe, and North America. A new study published in npj Climate and Atmospheric Science investigates the paradox of these record-breaking cold spells and assesses future risks in a changing climate.

A cold spell hit Beijing. (Image by Qian Cheng)

Led by Professor Qian Cheng from the Institute of Atmospheric Physics at the Chinese Academy of Sciences, in collaboration with Dr. Aiguo Dai from the University at Albany, State University of New York, and Prof. Zhang Xiaoye from the Chinese Academy of Meteorological Sciences, the study examines the mid-December 2023 cold wave that swept across eastern China. The team analyzed the role of anthropogenic climate change in driving or suppressing such extreme events and projected how similar cold events might evolve in the future.

“Our findings confirm that human-induced climate change is actually weakening extreme cold events,” said Professor Qian. “The record-breaking cold in December 2023 was primarily caused by unusual large-scale atmospheric circulation patterns, which accounted for 83% of its intensity. Meanwhile, the warming effect of climate change reduced the event’s severity by up to 22%.”

The study's attribution analysis, based on climate model simulations, reveals that due to anthropogenic warming, the likelihood and intensity of 2023-like cold events have already dropped by over 92% and 1.9°C, respectively, compared to a world without human influence. Furthermore, such events are projected to become even rarer and milder by the end of the century—decreasing in frequency by 95% and in intensity by more than 2°C under an intermediate-emissions scenario.

However, the study also highlights that while extreme cold events are becoming less common, they have not disappeared entirely. “If carbon neutrality is achieved and global warming stabilizes at 1.5°C, we could see cold extremes similar to those we experience today,” Qian explained. “That means societies still need to be prepared for sudden cold snaps, even when the 1.5 °C target of the Paris Agreement is achieved.”

As the debate over cold extremes in a warming world continues, this research provides critical insights into the inter-competition of climate dynamics that drive them—and the importance of adaptation strategies to mitigate their impacts.