资源环境科技发展态势分析平台

The extreme El Nino events, such as those which occurred in 1982-1983, 1997-1998, and 2015-2016, exerted devastating impacts in many parts of the globe. Hence, it is crucial to understand the precursors of such extreme events. Nevertheless, each El Nino event has its own characteristics even in the initiation. Here, we show that the development of early-spring equatorial central Pacific warming forced by the increased solar radiation due to a suppressed convection was a crucial factor in developing the 1982-1983 extreme El Nino event. The central Pacific warming anomalies in the spring of 1982 were induced by atmospheric subsidence connected to the northern subtropical Pacific convection, subsequently reinforced by a reduced evaporative cooling via westerly anomalies. On the other hand, springtime warming anomalies over the equatorial central and eastern Pacific regions during other extreme El Nino events were induced mainly by oceanic dynamical processes.