North Pacific meridional mode has larger impacts on El Nino evolution than the March Madden-Julian Oscillation.

ABSTRACT: The El Niño-Southern Oscillation (ENSO) is a key driver of global climate variability. Early-season westerly wind bursts (WWBs) have long been suggested to be important for ENSO evolution and diversity, with the Madden-Julian Oscillation (MJO) among the main sources of WWBs. However, MJO's contribution to ENSO evolution has been difficult to quantify. Here, using an ensemble hindcast approach specifically designed to isolate internal atmospheric variability, we evaluate the influences of March MJO on subsequent ENSO development. Our results show that the March MJO, under favorable background conditions, by itself has limited impacts on ENSO due to weak equatorial air-sea coupling in spring. In comparison, the North Pacific Oscillation-induced meridional mode exerts a more sustained influen

SUBMITTER: Liang Y 

PROVIDER: S-EPMC12422190 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature