We present prediction runs with 2 intermediate ocean-atmosphere coupled models of the tropical Pacific. The two models (Model 1 and Model 2) differ solely from the atmospheric component. The ocean component is a 3 baroclinic mode linear model. Model 1 uses a "shallow-water" model for the atmospheric part (Gill's type). Model 2 uses a statistical atmospheric model based on the SVD decomposition of observed sea surface temperature (SST) and wind stress anomalies. Models 1 and 2 are detailed in Dewitte (2000), Gushchina et al. (2000) and Dewitte et al. (2002). Initial conditions for the prediction runs are produced in a coupled mode by nudging the observed winds (FSU winds for the period 1961-1992, ERS1-2 winds from may 1992 until september 2000, QuikSCAT winds from october 2000) to the simulated winds as in Chen et al. (1995). Forecasts are an ensemble average of 12 prediction runs starting from initial condictions obtained by adding random noise to the wind forcing like in Kirtman and Schopf (1998).
Predictions for an initialization with observations in February 2009:
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