El Niño–Southern Oscillation Evolution Modulated by Atlantic Forcing

Abstract

The El Niño–Southern Oscillation (ENSO) exerts a strong influence on tropical Atlantic variability, but it is also affected by Atlantic forcing. Previous research has proposed three Atlantic precursors for ENSO: the North tropical Atlantic, the equatorial Atlantic, and the entire tropical Atlantic. However, the relative importance of these Atlantic precursors for ENSO remains unclear. Here, we present evidence from a set of multimodel partial ocean assimilation experiments that equatorial Atlantic cooling is the main contributor for weakening equatorial zonal winds in the Indo‐Pacific sector and subsequent ocean warming in the tropical Pacific. Opposite tendencies occur for a warmer equatorial Atlantic. The equatorial Atlantic affects the interbasin climate seesaw between the Atlantic and Pacific through an atmospheric zonal Wavenumber 1 pattern. However, model mean state biases and systematic errors prevent a precise assessment of the response times for the equatorial Pacific trade winds to Atlantic forcing.

Document Details

Document Type
Pub Defense Publication
Publication Date
Aug 01, 2020
Source ID
10.1029/2020jc016318

Entities

People

  • Michael J. McPhaden
  • Simon Wang
  • Takashi Mochizuki
  • Yoshimitsu Chikamoto
  • Zachary F. Johnson

Organizations

  • Kyushu University
  • National Oceanic and Atmospheric Administration
  • United States Bureau of Reclamation
  • United States Department of Defense
  • United States Department of Energy
  • Utah State University

Tags

Fields of Study

  • Environmental science

Readers

  • Atmospheric Science/Meteorology