中国北方沙尘暴与气象要素关系的初步研究

为研究沙尘暴形成机理以及各气象要素对沙尘暴的作用，利用1954～2000年我国北方地区7个台站的月降水量、大风日数、月平均气温和沙尘暴日数资料，以相关性分析为基础，采用了建立大风修正指数，线性拟合，滑动相关的方法，深入探讨其相关关系。结果表明沙尘暴与同期降水呈负相关，而与前一年降水的相关不明显，但有极值对应；与大风和大风修正指数呈明显正相关，并从结果比较可知大风修正指数可以很好地反映沙尘暴的发生规律；沙尘暴日数与前冬气温呈负相关，但是减去趋势后负相关消失，这反映了两者的相关关系主要是趋势相关；计算20年滑动相关，由6个台站一致的变化趋势得出结论：相关值的大小与下垫面的荒漠化程度有很大关系。

On the Relationship between Sandstorm and Meteorological Elements in China

To investigate the mechanism of the sandstorm, based on the correlation analysis, the establishment of the gale modified index, trends analysis, and moving correlation method, the correlation between Sandstorm in North China and meteorological elements is conducted, utilizing surface observing data from 7 meteorological stations in China during the period of 1954-2000, including monthly rainfall, gale dates, mean monthly temperature and sandstorm frequency. The results show that the correlation coefficient between the sandstorm frequency and rainfall at the same period is negative, but the correlation coefficient between the sandstorm frequency and the previous year rainfall is not obvious, and their extrema are corresponding. The correlation between the sandstorm and gale frequency and gale modified index is positive, the comparison shows that the gale modified index can well indicate the rule of sandstorm. The correlation between it and the previous winter temperature is negative, after eliminated the trend, the negative correlation does not exist, so their correlation is due to their trend. Through 20 years moving correlation analysis, from which the 6 stations show the same trendency, so it shows that their correlation is related to the degree of underlying surface desertifieation.