Influence of Atmospheric Rivers on Lake Ice Phenology in the Northern Hemisphere

Atmospheric rivers (ARs) can rapidly alter regional hydrothermal conditions and directly affect lake ice. This study presents the first assessment of AR impacts on lake ice phenology across the Northern Hemisphere. AR events were associated with positive anomalies in temperature, rainfall, and snowfall, as well as negative anomalies in solar radiation. These climate anomalies showed significant correlations with lake ice phenology. Between 1951 and 2022, AR-associated climate anomalies explained on average 20%, 33%, and 30% of the long-term variations in ice-on, ice-off, and ice duration, respectively, with stronger effects on North American lakes than on Eurasian lakes. Temperature anomalies contributed approximately half of the total explanatory power. Furthermore, extreme lake ice events corresponded closely to the frequency and intensity of AR events. These results indicate that ARs play a significant role in driving interannual variability in lake ice phenology across the Northern Hemisphere.