摘要
10~30d延伸期的可预报性既依赖于初始条件,也与缓变的下垫面有关,寻找延伸期时段内可预报性较高的低频特征,识别延伸期的可预报性来源及影响的物理机制是提高延伸期预报水平的关键。近年延伸期可预报性来源、热带大气季节内振荡监测预测和影响等领域的研究取得较大进展,提出和应用了动力统计相结合以及大气低频信号释用等新的延伸期预报方法。对延伸期可预报性来源及其与初值和外强迫异常的关系分析表明,海气相互作用能提高亚洲和西太平洋区域延伸期时段大气环流和要素的可预报性。热带大气季节内振荡、平流层爆发性增温以及各种次季节尺度的海气、陆气耦合作用和大气响应均为延伸期预报提供了重要的可预报性来源。由于数值模式延伸期时段的预报性能与实际业务需求还存在一定距离,基于动力统计相结合和物理统计的延伸期预报方法被广泛应用于业务预报,表现出一定的预报技巧。
The 10-30 d extended range forecast (ERF) fills the gap between traditional weather forecast and short-term climate prediction, and it plays an important role in the decision making of disaster prevention and mitigation. Therefore, ERF becomes one hot topic in both scientific research and predictive operations. The research progress and operational status of ERF are reviewed from three aspects, the source of predictability, sub-seasonal climate phenomenon and operational predictions. The research achievements on predictability of ERF and its applications are specially emphasized, and some new forecasting methods of ERF in recent years are summarized. At last, key scientific issues and technical problems are raised and some thoughts and possible ways enhancing the predictive skills of ERF are proposed. ERF exceeds time limits of traditional daily weather forecast, largely beyond the atmospheric memory of initial conditions, while it is too short to consider the variability of the ocean, which makes it difficult to beat persistence. Fortunately, recent years, some research work indicates the existence of some important sources of predictability at this time range, such as Madden-Julian oscillation (MJO), ENSO, soil moisture, snow cover and sea ice, stratosphere-troposphere interaction, ocean conditions, tropics-extratropics teleconnections, etc. Verification results of numerical model indicate that upper bounds of the prediction skill can be extended to 4 weeks. However, the complexity and diversity of mechanisms associated with the connection between source of predictability and climate variables prevent the potential predictability from being transformed into realized forecast skill. The effective forecast of most climate variables of numerical model is still limited within 2 weeks. Although the direct application of numerical dynamical model output in ERF is unsatisfactory, some research institutes and operational centers still conduct a series of scientific research and propose some practical methods. According
作者
章大全
郑志海
陈丽娟
张培群
Zhang Daquan;Zheng Zhihai;Chen Lijuan;Zhang Peiqun(Laboratory for Climate Studies,National Climate Center,China Meteorological Administration,Beijing 100081)
出处
《应用气象学报》
CSCD
北大核心
2019年第4期416-430,共15页
Journal of Applied Meteorological Science
基金
国家重点研究发展计划专项(2017YFC1502303)
国家重点基础研究发展计划(2015CB453203)
国家自然科学基金项目(41605078,41875101,41730964)
关键词
延伸期预报
可预报性
季节内振荡
extended range forecast
predictability
intra-seasonal oscillation
