ENSO's changing grip on Bering Sea ice: The emerging control of the North Pacific meridional mode.

ABSTRACT: Bering Sea winter sea ice (BSWI), vital for regional climate, ecosystem, and livelihoods, is significantly influenced by El Niño-Southern Oscillation (ENSO). Here, we identify a shift in the ENSO-BSWI relationship. Pre-mid-1990s, traditional eastern Pacific ENSO dominated, driving a positive ENSO-BSWI linkage; post-mid-1990s, more frequent central Pacific (CP) ENSO events reversed this relationship to negative. Observations and model experiments show that CP El Niño coupled with positive-phase North Pacific meridional mode (NPMM) redirects poleward-propagating Rossby wave trains, enhancing Bering Sea southerlies. This suppresses ice advection, intensifies warm air intrusion, and reduces BSWI. Strengthened CP ENSO-NPMM coupling and heightened NPMM variability amplify this teleconnection, in

SUBMITTER: Chen J 

PROVIDER: S-EPMC12629142 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature