浑善达克沙地气候因子对沙尘暴频率的影响

利用浑善达克沙地气象台站的常规气候资料,分析气候要素和沙尘暴频率的多年变化状况,建立能够很好描述该地区沙尘暴频率年际变化的沙尘暴指数,并建立适合浑善达克沙地气候特征的气候因子影响沙尘暴频率指数模型。结果表明,浑善达克沙地自1960年后气候逐渐变暖,并有微弱变湿趋势,沙尘暴年日数自1998年起波动增加,2000年出现极大值;沙尘暴年日数与沙尘暴指数的相关系数达0．7左右;建立的气候影响指数模型,能够用来解释当前该地区沙尘暴频率的分布格局。

Effects of Climatic Factors on the Occurring Frequency of Dust Storms over the Hunshan Dake Sandland

The Hunshan Dake Sandland is located in the farming-pastoral ecotone in east Inner Mongolia, it belongs to the semiarid temperate grasslands climate, and the ecological environment is extremely vulnerable and sensitive. Moreover, the Hunshan Dake Sandland and its peripheral regions are the ecological barriers of Bejing Desertification of the grasslands in these regions has become more serious due to the continuous droughts since recent years, and the sandland has become as one of the main sand-dust sources of occurring dust storms in north China. In this paper, the change of climatic factors and of occurring frequency of dust storms is analyzed by using the meteorological data collected by the meteorological stations on the sandland, the indexes of dust storms, which can be used to well describe the interannual change of dust storm frequency, are developed, and the model containing the climatic factors affecting the occurring frequency of dust storms over the sandland is also developed. The results show that the gradual climate warming and slightly wetting over the sandland have occurred since 1960, and the days of occurring dust storms increased in a fluctuation way after 1998 and to the highest value in 2000; the correlative coefficient between the days of occurring dust storms and the dust storm indexes is about 0.7, and the current distribution pattern of the occurrence of dust storms in the region can be explained by developing the models.