利用九华山不同海拔高度测站及区域自动气象站资料,对比分析山区与平地区雾的气候特征,研究山区雾的形成机理。结果表明：山区雾年际变化较大,并呈逐年递减趋势,平地区雾呈逐年缓慢递增趋势,山区雾生成时间峰值在05时前后,比平地区约早1 h,但出雾频率最高的是在08时,比平地区迟1 h。山区夜间降温≥6℃的雾日占总雾日数的74.4%,气温日较差≥7.0℃的雾日占总雾日数的80.9%,雾日多出现在日平均风速〈3 m/s的条件下,83.9%的雾日有近地面逆温层存在,并且雾日数与逆温强度呈正相关。喇叭口地形辐合作用有利于水汽在喇叭口底部区域达到饱和而形成雾,微风条件对辐射雾的形成非常有利,如果近地面层有风场的辐合作用,更有利于雾的形成与维持,森林小气候作用也有利于雾的形成。%Based on Jiuhua Mountain meteorological stations at different altitudes and regional automatic weather station data, the com- parative analysis was made about climate characteristics of fog in mountainous area and fiat area, and fog formation mechanism was ana- lyzed also. The results show that the annual change of fog in mountainous area decreased year by year, but fog in flat area presented slowly increasing trend, the peak time of fog occurrence in mountain area was at about 05:00, which was one hours earlier than that in the flat area, but the highest frequency of fog occurrence at 08:00, which was one hours later than that in the flat area. The percentage of fog days occurred when temperature cooling at night was more than or equal to 6 ~ was 74.4% , and the percentage of fog days oc- curred when the daily temperature range was more than or equal to 7℃ was 80.9%. When daily mean wind speed was less than 3 m/ s ,fog weather would appeared, and on 83.9% fog days the inversion layer existed near the ground, and fog days was positively related to inversion intensity. The convergence role of the bell mouth topographic made water vapor in the flared bottom area to reach saturation and formed fog, and breeze conditions was advantageous to radiation fog formation, if there was wind field convergence near surface, it was more conducive to the formation and maintenance of the fog, and forest microclimate effects also contribute to fog formation.
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