渭河上游干旱特征与降水对天水市水资源的影响

The Drought Character in Upper Area of Weihe River and Precipitation Influence on Water Resource in Tianshui

文中利用气象和水文观测资料,分析了渭河上游50a的干旱特征及降水对天水市水资源的影响,分析表明,渭河上游年降水在空间上有量的差异,但在气候变化趋势上基本一致;降水量存在17、13、11和3a的周期;水资源对气候变化有很强的敏感性,岷县降水量的年际变化对渭河水资源变化有很强的指示性;气候阶段性变化比年际变化对水资源所造成的影响严重;未来20a渭河流域降水很可能呈缓慢上升趋势。

According to weather and water data, the drought character in upper area of Weihe River and precipitation influence on water resource are analyzed. The results indicate that annual precipitation is different but climatic tendency is same from place to place,there is 17、13、11 and 3 annual circulation period, and water resource is sensible to climate variation, the annual precipitation change in Mingxian country may cause obvious change in run-off of Weihe River.The stage climatic change do greater harm than the annual climatic change,perhaps the precipitation over upper area of Weihe River gradually increases in following 20 years.