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Improving ENSO simulations and predictions through | 
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the ECCO ocean state estimation  | 
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 | 
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Dietmar Dommenget and Detlef Stammer | 
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 | 
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The global ECCO ocean state estimation procedure is used to simulate  | 
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and forecasts of tropical Pacific SST and sub-surface fields on seasonal | 
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time scale. As compared to a traditional ENSO assimilation and prediction | 
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procedures, the hindcast of the constrained ocean state is much closer to  | 
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observed conditions. The skill of the 12 month lead SST forecast in the | 
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equatorial Pacific appears to be similar in both assimilation, but | 
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the optimizations leads to better skills in the SST anomaly correlations.  | 
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Although our current forecast system is strongly limited by the estimation  | 
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of atmospheric forcing corrections, the results see to suggest that | 
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the forecast system would benefit if adoint optimizations are performed | 
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with coupled ocean-atmosphere systems in which the coupling is | 
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part of the control vectors of the adjoint optimization. | 
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