El Ninõ-like events observed in the Tropical Pacific

The data provided by ships of opportunity operated by the SURTROPAC Group (Centre ORSTOM de Noumea) are used to study surface temperature and salinity. In 1979 and 1982, negative anomalies of salinity occurred in the equatorial western Pacific. These are usually induced by El Nino events, although no El Nino was noticed in the eastern Pacific during the beginning of the year. However, along the Tahiti-Panama shipping route, the warm season in 1979 and 1982 lasted longer than usual. Empirical orthogonal analysis applied to the surface temperature along shipping routes in the eastern and central Pacific reveals other events with the same signature as the 1976 El Nino. A weak event occurred in 1979, and the beginning of the 1982 major event is seen. Eastern, central, and western anomalies are significantly correlated.