انتخاب متغيرها به منظور پهنه بندي اقليم بارش ايران با روشهاي چندمتغيره

Selection of Variables for the Purpose of Regionalization of Iranʹs Precipitation Climate Using Multivariate Methods

Study of precipitation climate, in every region is an important task from the view of agricultural crop production, drainage of agricultural and urban lands, erosion, flood, drought, water resources research, civil and urbanization. In the present study regionalization of precipitation climate is of interest. Because the type and number of used variables in determination of regional precipitation climates can lead to the production of different climate boundaries, so it has been tried to introduce the most important variables by including all available ones efficient in precipitation climate. These selected variables were then used for regionalization using factor and cluster analysis. For regionalization of precipitation climates in the country (77 weather stations) data from 1956 to 1998 have been used. From a total of 57 variables, twelve were selected using Krzanowskiʹs proposed method. The countryʹs area has been divided into 6 homogenous and heterogenous regions. The test, applied for regional homogeneity was H-Statistic and for choosing suitable distribution to data was Z-Statistic test. The growth curves were obtained and illustrated for all regions.