ENSO Forecast Model Initialization Using an Analogue Approach

Forecasting using analogue matching techniques have been explored for decades with varying success. The need for a very large climate record often makes analogue matching not feasible as either a long climate record does not exist or climate changes result in poor analogue matches. To overcome this hurdle, we employ the coupled general circulation model (CGCM), Community Climate System Model version 4 (CCSM4), to generate a long climate record.

In this study the viability of analogue forecasting El Niņo/Southern Oscillation (ENSO) using CGCMs is examined. CCSM4 is used to generate an artificial climate record for analogue matching with observed states of the Tropical Pacific Ocean. Seasonal ensemble hindcasts generated from analogue-matched initial states are then validated based on the Niņo 3.4 SST.