Interdecadal variability in the tropical Indian Ocean and its dynamic explanation

Interdecadal variability in the tropical Indian Ocean has been analyzed bas ed on the long-term climatic observational data. Case study showed that str ong interannual signals formed at the surface can penetrate the depth of se asonal thermocline, where the anomalies last a couple of years. Artificial time series based on damping with exponential decay of selected strong even ts agree well with the detected interdecadal variability in the tropical In dian Ocean. A possible dynamic explanation for interdecadal variability in the tropical Indian Ocean was proposed that irregular interannual signals c an lead to a slowly evolving climatic background with the interdecadal time scale through damping of the memory about anomalies in the seasonal thermo cline.