Presence/role of twin gyres in the El Nino 3.4 domain

摘要

El Nino is the 'weather pulse' of the world climate, arising out of the interactions between ocean and atmosphere. In the ocean, it is caused and cushioned by the interaction of the Kelvin and Rossby waves, but the mode/method and the consequences of their interaction are still not clear. It has been shown in the Indian Ocean that such interference results in a system of westward propagating equatorial twin gyres super(1). By analyzing the surface circulations of a global model (MIT-OGCM) as well from WOCE, TOPEX SSHs, TAO and AVHRR SSTs, a similar feature of the Pacific twin gyres along the equator in the El Nino, domain, especially in the Nino 3.4 domain (170 degree E-120 degree W, 10 degree S-10 degree N) is reported. The possible role of these eddies in inducing warmer temperatures with reference to the El Nino period is investigated.