面向可能最大洪水-风暴潮复合情景的热带气旋强度-降水参数设定方法研究

A study on the method of setting tropical cyclone intensity-precipitation parameters for the probable maximum flood-storm surge composite scenario

  • 摘要: 为开展可能最大洪水(PMF)-风暴潮灾害情景设定,在已有可能最大热带气旋(PMTC)参数设定研究的基础上,引入热带气旋降水气象参数,并探索了热带气旋强度-降水参数设定的方法框架.基于中国气象局的热带气旋最佳路径-强度、美国联合台风预警中心的最大风速半径,以及中国自动站与 CMORPH 融合降水等数据,统计分析了热带气旋最大风速、中心最低气压、最大风速半径、每小时降水量等参数间的定量关系,并构建了PMTC关键参数设定的方法.结果表明:1) 基于已有PMTC参数设定方法,引入降水参数后,能够设定不同等级热带气旋登陆时的关键参数,为PMF-风暴潮复合情景模拟提供输入数据;2) 通过线性拟合以及多倍标准差,能够确定参数可能的最大上限,MSW与最低气压、最大风速半径呈负相关关系,与每小时降水的最大值、第99百分位值,以及总和存在明显的负相关外包络线;3) 若样本分布较分散,可通过分段研究与极值函数拟合相结合的方法,探索数据分布的不确定性及参数间相关关系,在此基础上,探索不同概率水平的每小时降水总量以及外包络线.研究结果可为沿海地区热带气旋防灾减灾救灾和风险管理提供决策依据.

     

    Abstract: To set probable maximum flood-storm surge composite disaster scenario, the parameter of tropical cyclone precipitation was added to previous studies.Thus, constructing a methodological framework to set tropical cyclone intensity-precipitation parameter is explored.Best track dataset of tropical cyclones from China Meteorological Administration, the radius of maximum winds from the Joint Typhoon Warning Center, and precipitation data obtained by fusing observations from Chinese automatic stations with CMORPH products, were used to statistically analyze the quantitative relationships between key parameters of tropical cyclones and to construct a method to set parameters (maximum sustained wind, central minimum pressure, radius of maximum wind, and hourly precipitation).Previous methods to set parameters for probable maximum tropical cyclones were used, addition of precipitation as a meteorological parameter could better develop critical parameters at different levels of tropical cyclone landfall and provide input data for probable maximum flood-storm surge composite scenarios.The upper limit of probable maximum intensity could be effectively determined by linear fit of parameter relationship plus multiple standard deviations.Central maximum wind speed was found negatively correlated to central minimum pressure and radius of maximum wind.Significant negative outer envelope correlations to maximum hourly precipitation, 99th percentile of hourly precipitation, and total hourly precipitation were found.If sample distribution is scattered, uncertainty of data distribution and correlation between parameters could be explored by a combination of interval discussion and extreme value function fitting.Total hourly precip