影响闽南核电厂热带气旋特征及其最低气压的计算

CHARACTERISTICS OF TROPICAL CYCLONES IMPACTING SOUTHERN FUJIAN COAST AND ESTIMATE OF MINIMUM CENTRAL PRESSURE

根据1949—2008年台风资料,采用耿贝尔-Ⅰ型极值法和皮尔逊-Ⅲ频率分布以及确定论法,统计计算了影响闽南热带气旋的可能最低中心气压。结果表明:耿贝尔-Ⅰ型和皮尔逊-Ⅲ型对热带气旋中心最低气压值的实况拟合较好,且两者差异不大,千年一遇值分别为867.4 hPa和868.1 hPa;确定论法是根据大气动力学原理,估算值为867.28 hPa,接近概率论千年一遇值。鉴于皮尔逊-Ⅲ型对参数调整带有一定的随机性,而确定论计算方法具有充分的理论依据,且其估算值又是所选计算法中最小的,因此从安全保守角度考虑,闽南地区可能最低热带气旋中心气压采用确定论法的结果是合理的。

Based on tropical cyclone（TC） data for the period 1949—2008 and following the Gumbe –I method,Pearson-Ⅲ method and determinacy method,this article estimates the climate characteristics of TCs and their possible minimum central pressure.Results show that the observed minimum central pressure of TCs agree well with the results with the above methods,and there are little difference between them（in a 1 000 yr return period the minimum central pressure is 867.4 hPa and 868.1 hPa,respectively）.Established by the theory of atmospheric dynamics,the determinacy method yields a result of 867.28 hPa/1 000 years,only a little smaller than the result of the probability method.Because of randomicity in parameter adjustment with the Pearson-Ⅲ method whereas the determinacy method is theoreticaly solid,the estimates of the latter are the smallest of the three methods.It is therefore reasonable,for security and conservative concerns,to adopt the result determined with the determinacy method as the possible maximum intensity of TC（with the central pressure being 867.28 hPa in a 1 000 yr return period）.