华北地区水资源的气候特征

CLIMATE CHARACTERISTICS OF WATER RESOURCES IN NORTH CHINA

利用华北地区２７ 个台站１９５１ ～１９９５ 年月平均气温及月降水总量资料，用ＥＯＦ分析方法及高桥浩一郎公式计算并分析了华北地区水资源的气候特征。通过分析初步得出：在气候变暖的背景下，华北地区降水呈减少趋势。特别是从１９６５ 年以来持续减少。陆面蒸发呈增加趋势，全区变化较为一致，中心在华北地区中部的济南、临沂一带。水资源呈减少趋势，１９６７ 年以后迅速减少。主要表现形式为全区一致型、南北差异型、东西差异型，水资源变化主要受降水变化的影响；冬、春季变化较为简单，夏季较复杂。

The climate characteristics of water resources in North China are analyzed by EOF method and Gaoqiao Equation using monthly precipitation and monthly mean air temperature data of 27 stations in North China from 1951～1995. We have obtained some preliminary results: (1) Under the background of climate warning, precipitation in North China had decreased tendency during the period of 1951～1995, especially since 1965, the precipitation decreased continuously. The maximum decreasing of precipication occurs in summer. (2) Land evaporation increases all over North China in above period, the maximum center is located at central part of it,Jinan and Liyi,Shandong province. (3) Water resources in North China were decreased from 1951 to 1998, but the decreases of water resources were very quickly after 1965. There are 3 distribution types: i.e. whole district is the same, north and south part difference, and east and west part difference. Water resources are mainly influenced by precipitation. The variations are simple in winter and spring, but complex, in summer.