台风倒槽引发特大暴雨的对比分析

以冷空气侵入8712台风倒槽在温州引发特大暴雨与6122台风倒槽无冷空气侵入仅在温州引发中雨的倒槽降水显著差异为例,运用湿度、Q矢量散度、潜热等动力和热力物理量,探讨了冷空气与台风倒槽相互作用在温州引发特大暴雨的原因,同时与无冷空气侵入情况下台风倒槽内物理量场进行对比,研究台风倒槽降水巨大差异的内在原因。发现在厦门以南至广东东部登陆的台风,在浙东南沿海形成台风倒槽,秋季低层弱干冷空气易于侵入台风倒槽与强暖湿平流相互作用,使得斜压增强,不稳定能量释放是产生倒槽特大暴雨的重要原因。

Comparative Analysis on Extraordinary Heavy Rainfall Caused by Inverted Trough of Typhoon

Taking the significant inverted trough difference between the extraordinary heavy rain caused by the inverted trough of 8712 typhoon with cold air invasion and medium rain only occurred in Wenzhou of the inverted trough of 6122 typhoon as an example,the reasons caused the extraordinary heavy rain of the interaction effect between cold air and inverted trough of typhoon in Wenzhou were discussed by using the dynamic and thermal physical quantities such as humidity,Q vector divergence and latent heat.And it was compared with the physical quantity field in the inverted trough without cold air invasion to probe into the inner reasons for greater rainfall difference of typhoon inverted trough.It was found that typhoons landed from south of Xiamen to east of Guangdong formed the inverted trough of typhoon on the southeastern coast of Zhejiang.Weak dry cold air in lower levels in autumn was easy to invade into the inverted trough of typhoon and interact with the strongly warm and wet advection so as to strength the baroclinic pressure.Unstable energy release was the important reason that caused the extraordinary heavy rain of the inverted trough.