宁夏降水关联维与混沌特征分析

利用宁夏23个气象站建站以来月、季、年降水资料,在非线性系统动力学理论指导下进行了关联维特征分析。结果表明:①南部六盘山区、中部韦州为高值频发区,低值多集中于北部地区。极大、极小值出现站点相对集中。夏、秋各月关联维数值较高,冬、春月份较低。②冬、春季节降水关联维分布散乱,极值位于六盘山区。夏、秋季节韦州为高值中心,梯度较大。最大值位于中、南部,最小值位于北部。③年降水的最大关联维数出现在北部的陶乐,最小值位于中部的同心。④混沌是宁夏月、季、年降水的普遍特征。出现频率与降水量对应较好,但混沌强度与降水量并不存在简单的对应关系。⑤处于气候干旱、半干旱区的宁夏降水具有显著的非线性特征,且行为十分复杂。

Correlation Dimension and Chaos Analysis on Precipitation in Ningxia

Using the precipitation data of 23 meteorological stations of Ningxia,the characters of correlation dimension were analyzed with non linear dynamic system theory.The results showed that:①The high values of correlation dimension occur frequently in southern mountain and central area and the low values mostly locate in north.The extreme values concentrate in some certain areas.The values keep high in the summer and autumn months.②The correlation dimension scatters diversified in winter and spring with highest data in the south mountain,and the high centers move to mid area in summer and autumn seasons with high gradient.③The highest correlation dimension of annual precipitation appears in north and the lowest in central area.④The chaos is common for the monthly,seasonal and annual precipitation in Ningxia.The frequency of chaos responses the amount of precipitation quite well but there is no simple relation between the intensity of chaos and precipitation amount.5.There is significant non linear feature of precipitation and the behavior of precipitation in Ningxia which has an arid,semi-arid climate is very complex.