PRECIS模式模拟陕西未来干旱变化趋势

Simulation of Drought Change Trend in Shaanxi Province in the Future Based on PRECIS

[目的]预测陕西未来干旱变化趋势。[方法]利用英国Hadley气候中心的区域气候模式系统PRECIS,以降水量距平百分率为评价指标,模拟了气候基准时段(1971～1990年)陕西干旱变化趋势,并预测了陕西2071～2100年的干旱变化趋势。[结果]气候基准时段陕西干旱频次模拟值很好地模拟出了干旱北多南少的分布格局;未来陕西全省2级以上干旱年均发生频次自北向南逐渐减少,陕北北部最多(大于4次),陕南南部最少(小于2.5次);陕北榆林南部以南到延安全市、关中东部(含渭北)以及陕南西部未来干旱频次有所减少,而陕北北部、关中西部秦岭地区和商洛地区有所增加。[结论]该研究为陕西未来干旱变化的研究提供了理论参考。

[Objective] The aim was to predict the change trend of drought in Shaanxi Province in the future.[Method] Based on the regional climate model PRECIS from English Hadley Climate Center,taking precipitation anomaly percentage as assessment index,the change trend of drought in Shaanxi Province in reference years（1971-1990） was simulated,and then the change trend of drought in Shaanxi Province from 2071 to 2100 was predicted.[Result] The simulated value of drought frequency in reference years could simulate the distribution of drought better,namely drought frequency was high in north and low in south;the annual mean frequency of second-class and upwards drought in the future decreased gradually from north to south,and it was highest in northern Shaanxi（above 4 times） and lowest in southern Shaanxi（below 2.5 times）;drought frequency in the future went down in northern Shaanxi from southern Yulin to Yan＇an,eastern Guanzhong（including Weibei） and the west of southern Shaanxi,while it increased in the north of northern Shaanxi,Qinling Mountains and Shangluo region in western Guanzhong.[Conclusion]The study could provide theoretical references for the research on the change trend of drought in Shaanxi Province in future.