Coupled ocean-atmosphere response to North Tropical Atlantic SST: Tropical Atlantic dipole and ENSO

Abstract

The coupled ocean-atmosphere response to changes of the north tropical Atlantic (NTA) SST is investigated using a coupled ocean-atmosphere general circulation model. The model explicitly demonstrates that a NTA SST anomaly can organize an inter-hemispheric SST dipole in boreal spring over both the tropical Atlantic and eastern tropical Pacific primarily through a coupled wind-evaporative-SST (WES) feedback. While the tropical Atlantic dipole eventually decays in summer and fall, the eastern tropical Pacific dipole subsequently evolves into an ENSO-like pattern through the seasonal migration of the ITCZ and coupled ocean-atmosphere feedbacks. Copyright 2005 by the American Geophysical Union.