咸宁市降水资源的GMK评价

A GMK APPROACH TO THE RESOURCE OF THE PRECIPITATION IN XIANNING CITY

本文根据我国东部季风区的降水特点,在干燥度的计算公式中引入均湿系数,提出了一个新的降水资源评价指标——生态水热系数GMK,并结合咸宁市的气象资料,划分了咸宁市的干湿特征期。

Xianning City is located in the area between the middle plain of the Yangtze River and the hill in the south side of the Yangtze River, with a rolling landform and a complex climate, for which it is failure to use the conventional indexes to express its aridity index. In this paper, we introduce a concept of the mean dampness into the caculation of the aridity index,and suggest a concept of the ecological water-and-thermal paramter GMK, whick can be experessed as GMK=K/W (1) where K=0.16∑t/R is the arid degree,and W=2t/p the mean damp degree,so that it is GMK=0.16∑tp/2tR (2) with considering of the need of the plant growth,and of the caculation and the meaning of the GMK parameter, we develop a range of indexes to identify the arid-and-damp periods. From which, the arid and damp periods of Xianning City are identified with the data of the rainfall resource. Comparing the result with the practice of Xianning City, it is shown that the GMK index is valid to evaluate the resource of precipitation.