粒子滤波同化在厄尔尼诺—南方涛动目标观测中的应用
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摘要
针对粒子滤波—目标观测方法的局限性,提出了能够克服该局限性的新目标观测方法,并将其应用于厄尔尼诺—南方涛动可预报性研究,揭示了东太平洋型厄尔尼诺事件和中太平洋型厄尔尼诺事件的目标观测敏感区。通过同化该敏感区的目标观测,显著减小了两类厄尔尼诺事件的预报不确定性,验证了新方法揭示的目标观测敏感区在改进厄尔尼诺预报技巧中具有更加重要的作用。
Considering the limitation of particle filter–target observation approach, the present study proposes a new target observation approach that can overcome this limitation. This new approach is then applied to the study of the predictability of El Ni?o–Southern Oscillation and reveals the sensitive areas for targeting observation associated with eastern-and central-Pacific El Ni?o events. By assimilating the target observations, the prediction uncertainties for the two types of El Ni?o events are significantly reduced. This result confirms that the sensitive areas revealed by the new approach, compared with other areas, can play a much more important role in improving the El Ni?o forecast skill.
Considering the limitation of particle filter–target observation approach, the present study proposes a new target observation approach that can overcome this limitation. This new approach is then applied to the study of the predictability of El Ni?o–Southern Oscillation and reveals the sensitive areas for targeting observation associated with eastern-and central-Pacific El Ni?o events. By assimilating the target observations, the prediction uncertainties for the two types of El Ni?o events are significantly reduced. This result confirms that the sensitive areas revealed by the new approach, compared with other areas, can play a much more important role in improving the El Ni?o forecast skill.
引文
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