资源环境科技发展态势分析平台

In this study, a long-term retrospective hindcast experiment is performed for the period from 1881 to 2016 with respect to tropical Pacific and Indian Oceans using a newly developed tropical intermediate coupled model. We focus on the predictability of the Indian Ocean Dipole (IOD) mode, especially its decadal variation. There is a considerable decadal variation in IOD predictability, with high skill after the 1980s and low skill in 1940-1960. This decadal variation is significant when the prediction target is observed in the boreal autumn and winter months. Further diagnostic analysis revealed that this decadal variation was primarily due to the decadal variation in the El Nino and Southern Oscillation (ENSO)-IOD relation that characterized the ENSO-induced precursor processes, strengthening the predictable IOD signal. Unlike the ENSO predictability that is substantially related to the ENSO signal, the IOD predictability is related to the ENSO-induced signal rather than the total IOD signal.