Teleconnections of rainfall anomalies and of the Southern Oscillation over the entire tropics and their seasonal dependence

The teleconnections between rainfall anomalies of selected areas within the tropics to each other are investigated with respect to their seasonal dependence, employing a cross correlation analysis technique. They are related to the Southern Oscillation. The magnitude and phase of these rainfall anomalies are computed for a typical El Niño event using a so-called composite analysis. Rainfall anomalies persist for almost an entire year over the islands of the equatorial Central Pacific, whereas over most areas in and around the tropical Indian and Pacific Ocean, they only tend to persist for a season or two. Seasons during which rainfall anomalies are most persistent (in a particular region) are also seasons, during which teleconnections between rainfall anomalies of these regions to each other are strongest. The Southern Oscillation is negative-correlated with the majority of the rainfall anomalies except for those from India, Indonesia, Hawaii and the Northcoast of Venezuela. The rainfall anomalies calculated for a typical El Niño event fit into this general scheme of teleconnections.