基于K指数的四川省3月干旱研究

Study on Drought in March of Sichuan Province based on K Index

为研究四川省3月干旱特征,利用四川省144个气象站近50年3月逐日降水、空气湿度等资料,用彭曼修正公式计算出K指数,用保证率方法对K指数干旱标准进行划分,采用克里金空间插值和一元线性回归方法,对四川省3月干旱进行时空特征分析,结果表明:用K指数能较好的研究四川干旱情况;空间分布特征:在3月干旱容易发生于甘孜州及攀西地区,特旱、重旱、中旱、轻旱在甘孜州西南部最为严重;年际变化特征:在3月盆地西南部、盆地西北部、盆地东北部干旱程度有加强,而川西高原、攀西地区、盆地中部、盆地南部干旱程度有减弱。

In order to study drought characteristics in March of Sichuan Province,K Index is calculated by Penman Monteith Equation with daily precipitation,air humidity from the data of 144 meteorological stations in the nearly 50 years,classifying drought by the method of guarantee rate.Kriging Interpolation method and Simple linear regression equation are used to analyze spatial and temporal characteristics in March of Sichuan.It can be safely concluded that the K drought index has a great significance to drought condition.Spatial distribution of drought：Ganzi Prefecture and Panzhihua-Xichang area witness drought and the southeast of Ganzi Prefecture are frequent to see severe drought,heavy drought,middle drought as well as light drought.Interannual variation：the degree of drought in the southeast,northwest and northeast of Sichuan Basin strengthens,while the degree weakens in the western Sichuan highland,PanzhihuaXichang area,the middle and south of the Basin.