The response of global atmospheric circulation to two types of El Nio

摘要

The composite and correlation analyses enabled determining the structure of the mutual response of the anomalies of zonal wind circulation and anomalies of sea surface temperature (SST) corresponding to two types of El Nio and La Nia. It is demonstrated that the signal coming to the atmosphere from the heat source in the ocean propagates from the tropics to the midlatitudes symmetrically relative to the equator in the years of the canonical event El Nio-Southern Oscillation (ENSO) and asymmetrically in the years of the ENSO Modoki; for the latter the propagation of the signal in the Northern Hemisphere is typical at tropical and subtropical latitudes only. The absolute values of anomalies as well as the correlations turn out to be higher for El Nio Modoki that is defined by the higher sensitivity of the atmosphere to the impact of the ocean in the areas of the localization of SST anomalies typical of this type of the ENSO.