1880年以来华北降水及水资源的变化

THE VARIATIONS OF THE PRECIPITATION AND WATER RESOURCES IN NORTH CHINA SINCE 1880

分析了１８８０ 年以来华北地区（ 太原、北京、济南、烟台和郑州） 降水的季节、年际和年代际变化。研究表明：华北降水存在着显著的年际和年代际变化，１８８３ ～１８９８ 年和１９４９ ～１９６４ 年是华北降水较丰沛时段，１８９９ ～１９２０ 年和１９６５ ～１９９７ 年华北降水处于偏少阶段，其中１９８０ ～１９９３ 年降水持续偏少，干旱现象严重。研究指出：华北夏季降水的年际和年代际变化与夏季东亚─西太平洋地区上空５００ ｈＰａ 位势高度场以及西太平洋副热带高压脊线位置的年际和年代际变化密切相关；９０ 年代后期，夏季西太平洋副热带高压脊线的位置偏北，估计未来５～１０ 年华北地区持续干旱现象将结束，降水可能会恢复到２０ 世纪５０ ～６０ 年代中期水平，有利于华北水资源增加。

A study on the precipitation in North China is presented since 1880. There were two plentiful rainfall periods,one was 1883～1898,the other was 1949～1964. There were two less rainfall periods,one was 1899～1920,the other was 1965～1997. The decade precipitation and evaporation in North China and their associated 500 hPa patters and west Pacific subtropical high during 1951～1997 are studied. The analysis of the summer dry and wet periods in North China reveals a reversal in the sign of anomalies over 500 hPa between middle latitude and low latitude. The precipitation in North China is positive(negative) anomaly when the west Pacific subtropical high lies north(south) than normal.