Evaluating Changes in the Multiyear Predictability of the Pacific Decadal Oscillation Using Model Analogs since 1900

In this study, we investigate the changes in multiyear predictability of Pacific decadal oscillation (PDO) since 1900. A newly developed method, model-analog is used to hindcast PDO from 1900 2015. Model-analog provides comparable prediction skills with traditional assimilation-initialized forecast but much lower computational costs. Our results show that have significantly changed over time. Specifically, could skillfully be predicted up 5 years advance 1910–1960, it can only 2–3 after 1960. We attribute these strength re-emergence process, where deep oceanic mixed layer temperature anomalies one winter reappear following winters. high-prediction-skill period, stronger process more predictable information, leading enhanced skills. study offers new insights into a long-time frame and sheds light on reasons behind low skill PDO.