Identifying unpredictable components of El Niño

For several decades, Linear Inverse Modeling (LIM) has provided skillful forecasts of tropical ocean sea surface temperatures. However, LIM's diagnostic properties are at least as useful as its prognostic properties. In this presentation, we discuss an updated method for using LIM to obtain time series representing stochastic forcing of El Niño and to quantify particular unpredictable contributions to LIM forecast error.