为改进对降水过程的分析和预告、我们介绍了一种新工具用来表示降水的历时、面积和深度的关系。这就是被称为历强函数的一个二元函数。如果有足够的资料,对任何降水过程都可求出它的历强函数来。本文中给出了求这个函数的方法和它的数值解,并指出它也是把熵原理与降水现象联系起来的一种预报降水的工具。

In order to improve the analysis and forecast on precipitation process,we introduce a new tool to express the relationship among the precipitation area,precipitation duration and its depth.This is a bivariant function named "Duration Intensity Function".For any precipitation process,if we have enough concern data,it is not difficult to work out its Duration Intensity Function.In this paper,we gave how to get this function from the concern data and to work out the figure of this function by numerical method.We point out this function is a tool to link the entropy principle with precipitation phenomenon.