|
| Impact of observational MJO forcing on ENSO predictability in the Zebiak-Cane model. Part I: Effect on the maximum prediction error |
| 用Zebiak-Cane模式探讨观测MJO强迫对ENSO可预报性的影响，第1部分：对最大预报误差的影响 |
| Received:September 06, 2013 Revised:December 24, 2014 |
| DOI： |
| Key words:El Nino–Southern Oscillation (ENSO) Madden-Jullien Oscillation (MJO) maximum prediction error Conditional Nonlinear Optimal Perturbation (CNOP) |
| 中文关键词: 厄尔尼诺-南方涛动 季节内振荡 最大预报误差 条件非线性最优扰动 |
| 基金项目:The National Natural Science Foundation of China (Grant No. 41405062) |
|
| Hits: 867 |
| Download times: 121 |
| Abstract: |
| With the observational wind stress data in Pacific and the Zebiak-Cane model, the impact of Madden-Jullien Oscillation (MJO) as external forcing on El Ni?o–Southern Oscillation (ENSO) predictability is studied. The observational data are analyzed with Continuous Wavelet Transform (CWT) and then used to extract MJO signals, which are added into the model to get a new model. After using the Conditional Nonlinear Optimal Perturbation (CNOP) method, the initial error which can evolve into maximum prediction error, model error and their join error are gained and then the Ni?o-3 indices and spatial structures of three kinds of errors are investigated. The results mainly show that the observational MJO has little impact on the maximum prediction error of ENSO events and the initial error affects much greater than model error caused by MJO forcing. These demonstrate that the initial error might be the main error source that produces uncertainty in ENSO prediction, which could provide a theoretical foundation for the adaptive data assimilation of the ENSO forecast and contribute to the ENSO target observation. |
| 中文摘要: |
| 本文用观测的热带太平洋风应力资料和Zebiak-Cane模式研究了季节内振荡(MJO)作为外强迫对厄尔尼诺-南方涛动(ENSO)可预报性的影响。观测资料用连续小波变换(CWT)分析后用于提取MJO信号，MJO加入模式得到新的模式。在使用条件非线性最优扰动(CNOP)后，得到了可发展成最大预报误差的初始误差、模式误差及其联合误差，然后考察了三种误差的Ni?o-3指数和空间结构的演变发展。结果主要表明观测MJO对ENSO事件的最大预报误差影响较小，初始误差比由MJO强迫产生的模式误差的影响大得多。这些说明初始误差很可能是产生ENSO预测不确定性的主要误差来源，从而可为ENSO预测的适应性资料同化提供理论基础，并对ENSO的目标观测做贡献。 |
|
HTML
Download PDF
View/Add Comment Download reader |
| Close |
