The Heat Sources and Sinks of the 1986–87 El Niño

Abstract

Abstract The heat balance of the coupled tropical ocean–atmosphere system during the Earth Radiation Budget Experiment (ERBE) period (1985–89) is analyzed in an attempt to better understand the heat sources and sinks of the 1986–87 El Nino. The analysis involves the use of radiation data from ERBE, circulation statistics from National Centers for Environmental Prediction–National Center for Atmospheric Research reanalysis, and the assimilated data for the Pacific ocean. Accumulation of heat in the equatorial upper ocean is found prior to the onset of the 1986–87 El Nino. The accumulated heat in the equatorial upper ocean comes from the surface heating, which exceeds the poleward transport of heat in the upper ocean. The accumulated heat in the upper ocean resurfaces in the eastern Pacific and the 1986–87 El Nino warming develops. The warming results in a substantial increase in the equator-to-pole heat transport in the equatorial ocean. The ocean warming is also accompanied by a significant increase in th...