This study investigates the impact of global warming on North American winter cold extremes. Contrary to previous findings suggesting a reduction in cold extremes due to decreasing temperature variability, the research shows that cold extremes have warmed significantly faster than the winter mean temperature since 1980. This amplified warming is attributed to both decreasing variance and changes in higher moments of the temperature distributions. Climate model simulations support the observed trends, and a detection and attribution analysis confirms the human influence on these changes in variability.

Russell Blackport, John C. Fyfe