我国东部的准经向降水带及其成因分析

Quasi-Meridional Precipitation Belt in East China and Its Formating Cause Analysis

根据我国东部明显的准经向地质构造,将我国的准经向类雨带划分为3型,分别为(1)3e:郯庐断裂及其以东沿海多雨,以西为少雨区;(2)3m:南北地震带附近的我国中部多雨,太行山—武陵山以东为少雨区;(3)3d:我国东部有两条多雨带或两条少雨带。夏季经向雨带几乎都出现在4月份地球自转减慢(ΔLOD>0)而且加速减慢(Δ2LOD>0)的条件下,这为汛期经向雨带的预报提供了一条有力的指标。

According to clear quasi-meridional geological structure in East China, the quasi-meridional precipitation is classified as three types, they are （1） 3e, there is rainy in Yanlu rapture and coastal areas at east of Yanlu, and there is dry at west areas of Yanlu; （2） 3m, there is rainy near north-south seismic belts in center China, and there is less rain at east of Taihang mountain-Wuling mountain; （3） 3d, there are two rainy belts or two dry belts in East China. Almost all of the meridional precipitation belts occurred in April during summer when rotation of the earth is slower （△LOD〉0） and when such slower is speed-up （△^2LOD〉0）. This gives an important index for prediction of meridional precipitation in flood season.