Enhanced interactions of Kuroshio Extension with tropical Pacific in a changing climate

Abstract Quasi-decadal climate of the Kuroshio Extension (KE) is pivotal to understanding North Pacific coupled ocean–atmosphere dynamics and their predictability. Recent observational studies suggest that extratropical-tropical coupling between KE central tropical El Niño Southern Oscillation (CP-ENSO) leads observed preferred decadal time-scale variability. By combining reanalysis data with numerical simulations from a high-resolution model linear inverse (LIM), we confirm CP-ENSO are linked through teleconnections. Specifically, atmospheric response excites Meridional Modes energize (extratropicstropics), in turn, teleconnections extratropical forcing (tropicsextratropics). However, both observations show KE/CP-ENSO non-stationary has intensified recent decades after mid-1980. Given short length record, it difficult attribute this shift anthropogenic forcing. using large-ensemble LIM intensification mid-1980 significant changes downstream response, which exhibit stronger imprint on subtropical winds excite modes CP-ENSO.