华北平原雾发生的气象条件

Meteorological Conditions for Fog Formation over North China Plain

根据1995-2000年全国基本气象观测站资料和T106模式内插到全国基本站的各种物理量资料，统计了华北平原12月雾发生前或发生时大气低层部分气象要素的特征，计算分析了气象要素的分布区间与雾发生频率之间的相互关系。结果表明，当近地面水平风很弱，相对湿度为80％～90%、温度露点差在2～4℃，饱和湿空气气层处于稳定或者弱不稳定状态以及近地面气温在3～9℃时雾的发生频率较高。

Based on the observation in the basic stations of the country and the interpolated data at these station points from the T106 model output for 1995-2000, the characteristics of the low-level atmospheric elements before and right at the fog occurrence over North China plain are analyzed. Moreover, the relationship between the elements distribution and occurrence frequency of fog is also given. The results,indicate that the weak wind, relative humidity in the range of 80%-90%, the depression of dew point in the range of 2-4℃, stable or weak instable atmosphere and the surface temperature in the range of 3-9℃ are favorable conditions for the occurrence of fog.