台风诱发的极端波高重现期值推算研究

Study on return value calculation of extreme wave height induced by typhoon

台风诱发的极端海洋环境参数重现期值推算对工程防灾具有重要意义,推算的合理性依赖于取样方法和概率分布模型。本文将台风过程取样法与指数威布尔分布模型结合起来,基于复合极值分布理论建立泊松-指数威布尔复合极值分布模型,将这种新型分布模型应用于台风下极端海洋环境参数的概率预测,推算出相应的重现期值。研究表明选取的计算点每年发生的台风频次符合泊松分布,指数威布尔分布对台风诱发的极端波高序列拟合情况较好,使用泊松-指数威布尔复合分布模型进行重现期值推算是可靠的,该复合模型在物理和统计意义上更加完善,计算结果稳定合理。

Return value calculation of extreme marine environmental parameters induced by typhoon is of great significance for engineering disaster prevention.The rationality of the calculation depends on the sampling method and probability distribution model.In this paper,the sampling method of typhoon process was combined with exponentiated Weibull distribution model.A Poisson-exponentiated Weibull compound extreme value distribution model was established based on the compound extreme value distribution theory.This new distribution model was applied to the probability prediction of extreme marine environmental parameters under typhoon,and the corresponding return values were calculated.The study showed that the annual typhoon frequency at the selected calculation points conformed to Poisson distribution,and the exponentiated Weibull distribution fitted the sequence of extreme wave height induced by typhoon well.It was reliable to calculate the return values by using Poisson-exponentiated Weibull compound distribution model.This compound model was more perfect in physical and statistical sense,and the calculation results were stable and reasonable.