Climate Dynamics

, Volume 35, Issue 1, pp 45–52

Tropical response to the Atlantic Equatorial mode: AGCM multimodel approach

Authors

    • Universidad Complutense de Madrid
  • B. Rodríguez-Fonseca
    • Universidad Complutense de Madrid
  • I. Polo
    • Universidad Complutense de Madrid
  • S. Janicot
    • LOCEAN/IPSL, CNRSUniversité Pierre et Marie Curie
  • S. Gervois
    • LOCEAN/IPSL, CNRSUniversité Pierre et Marie Curie
  • F. Chauvin
    • GAME/CNRM, Météo-France/CNRS
  • P. Ruti
    • Progetto Speciale Clima Globale, Ente Nazionale per le NuoveTecnologie, l’Energia e l’Ambiente
Article

DOI: 10.1007/s00382-009-0624-6

Cite this article as:
Losada, T., Rodríguez-Fonseca, B., Polo, I. et al. Clim Dyn (2010) 35: 45. doi:10.1007/s00382-009-0624-6

Abstract

On the frame of the AMMA-EU project, sensitivity experiments for an Atlantic Equatorial mode (AEM) which origin, development and damping resembles the observed one during the last decades of the 20th century, has been analysed in order to investigate the influence on the anomalous summer West African rainfall. Recent studies raise the matter of the AEM influence on the next Pacific ENSO episodes and also on the Indian Monsoon. This paper evaluates the response of four different atmospheric global circulation models, using the above-mentioned AEM sensitivity experiments, to study the tropical forcing associated with the Atlantic Niño mode. The results show a remote signal in both the Pacific and Indian basins. For a warm phase of the AEM the associated southward location of the ITCZ, with rising motions over the Equatorial Atlantic, leads to a global subsidence over the rest of the tropics, weakening the Asian Monsoon and favouring the La Niña conditions in the central Pacific. Although ocean–atmosphere coupled experiments are required to test the latter hypothesis, the present studies shows how the AEM is able to influence the rest of the tropics, a result with important implications on ENSO seasonal predictability.

Copyright information

© Springer-Verlag 2009