沙尘天气频率与相关气象因子的关系

The Relationship between Dust Event Frequency and Meteorological Factors

基于北京及其周边14个国家基本气象站1971—2000年气象资料的相关分析,指出风速、相对湿度是影响沙尘天气的关键气象因子,用这两个气象因子构建了月沙尘气象指数。月沙尘气象指数与沙尘天气频率具有较一致的周期性,沙尘天气日的沙尘气象指数是非沙尘日指数的倍数关系。另外,根据月沙尘气象指数在不同月份的分布特征,给出了相应的季节性气象指数计算方法,对14个站计算的结果显示,季节性气象指数与沙尘天气频率有很好的线性关系,这种线性关系具有明显的区域特征。

By analyzing the meteorological data of Beijing and other 14 typical weather stations from 1971 to 2000, which locate in the dust events route to Beijing from 1971 to 2000, it show that the wind speed and relative humidity are key meteorological factors to the dust events. On the base of correlation a- nalysis between the meteorological factors and the dust event frequency （DEF）, the dust meteorological in- dex （DMI） is given on the basis of the two key meteorological factors as a comprehensive effect on DEF. The results show that the index is consistent with the DEF, and the DMI of the dust events is multiple the non-dust events. At the same time, the calculating method of the seasonal index is given by analyzing the distribution characteristics of the index and the DEF on different months. It shows that there is obvious linear relation between the seasonal index the DMI, which has obvious regional feature.