If it weren’t for global warming, how much would this winter temperature pattern look like a typical El Niño winter when the stratospheric polar vortex winds didn’t break down? (left) Detrended January-March temperature anomalies during 2024 (same as the figure above) and (right) the average temperature anomalies during January-March El Niño winters (1958-2024) when no major sudden stratospheric warmings occurred. Anomalies correspond to departures from the 1958-2024 average temperatures. Similarities exist between the two figures particularly over North America, suggesting El Niño’s influence on winter temperatures. Note that the amplitude of the 2024 temperature pattern is much larger because it’s a single year rather than the El Niño temperature pattern which is averaged over numerous years. NOAA Climate.gov image, adapted from original by Amy Butler.