A possible approach for the decadal prediction of PDO

KeyWord:PDO;Decadal prediction;Increment method

Abstract:

      The Pacific Decadal Oscillation (PDO) is a leading mode of decadal sea surface temperature variability in the North Pacific. Skillful PDO prediction can be beneficial in many aspects because of its global and regional impacts. However，current climate models cannot provide satisfying decadal prediction of PDO and related decadal variability of sea surface temperature. A new prediction approach was proposed, i.e., the increment method. A series of validations demonstrate that the increment method effectively improves the decadal prediction on PDO and can well capture the phase changes of PDO with high accuracy. The prediction processes include three steps: (1) A five year smoothing is performed; (2) effective preceding predictors for PDO are selected，with all predictors and predictands in the form of a three year decadal increment (DI); (3) the prediction model is set up for PDO three year decadal increment (DI_PDO), and the PDO prediction can then be obtained by adding the predicted DI_PDO to the observed PDO three years ago. This new method can also be applied for decadal climate prediction of other modes (e.g., Atlantic multidecadal oscillation) and predictands (e.g.，sea surface temperature).