1. 国家气象中心，北京 100081
• 收稿日期:2020-10-10 修回日期:2020-11-15 出版日期:2020-12-10
• 通讯作者: 李勇 E-mail:meisl@cma.gov.cn;liy@cma.gov.cn
• 基金资助:
中国气象局气象预报业务关键技术发展专项“气象要素和重要天气过程延伸期预报关键技术”(YBGJXM（2020）04);国家科技支撑计划项目“10~20天延伸期天气预报技术研究”(2015BAC03B06)

### Review of the Application of MJO in the Extended Range Forecast

Shuangli Mei( ),Yong Li( ),Jie Ma

1. National Meteorological Centre，Beijing 100081，China
• Received:2020-10-10 Revised:2020-11-15 Online:2020-12-10 Published:2021-02-09
• Contact: Yong Li E-mail:meisl@cma.gov.cn;liy@cma.gov.cn
• About author:Mei Shuangli (1982-), female, Suihua City, Heilongjiang Province, Engineer. Research areas include medium and extended range forecast research. E-mail: meisl@cma.gov.cn
• Supported by:
the China Meteorological Administration Project for Key Techniques Development in Meteorological Forecasting Operation “Key techniques for forecasting meteorological elements and important weather processes during the extended range” [Grant No.YBGJXM(2020)04];The National Science and Technology Research Program in China “The research on weather forecast technology of 10-20 days extended range”(2015BAC03B06)

Tropical intraseasonal oscillation （MJO） is the main source of the extended range forecast. The research of the extended range forecast based on MJO is of great significance for the operational forecast. In this paper， the latest achievements of MJO in the prediction of precipitation， temperature and their extreme events， typhoon and monsoon in the extended range and the operational status of major prediction centers in which MJO is used for real-time monitoring and prediction were reviewed systematically. The theoretical support of MJO in the prediction of the extended range was summarized. Finally， the technical difficulties of MJO in the application of the extended range forecast， such as the establishment of forecast objects， the simulation of MJO by the current dynamic model， the physical connection between MJO and meteorological elements， and the evaluation of MJO's influence forecasting were analyzed， and the future development trends of MJO influence forecast in the ensemble forecast， multi-mode integration and strengthening the research on the influence of multiple seasonal oscillations on the weather were also pointed out.

Fig.1 Schematic diagram of the weather-climate seamless forecast[ 1 ]

Fig.2 Probability Skill Score of the weekly mean precipitation over the Northern Extratropics[ 91 ]
The horizontal axis is the lead time,and various color lines represent the scores of S2S multi-mode integration and 11 modes (MULI，ecmwf,UKMO,NCEP,CNRM,JMA,CMA,KMA，BoM,ECCC,HMCR,ISAC). The scoring period is over the period 8 June 2017 to 1 November 2018