六盘山区两类雾物理结构的初步观测研究

Preliminary observations study of physical structures of two typesof fog in Liupan Mountain areas

利用2020年在六盘山区观测高山雾获得的隆德、泾源、六盘山气象站地面能见度、温度、相对湿度、风等常规观测资料和微波辐射计温度、相对湿度垂直观测资料,初步分析了六盘山区大范围和仅山顶出现雾时的环流形势和温湿垂直演变特征。结果表明:六盘山区大范围雾过程和仅山顶雾过程都是受槽前暖湿气流影响,降温增湿导致的,两类雾过程地面相对湿度大于95%,以偏南风为主,隆德和泾源气象站能见度多在200 m以上,六盘山气象站一半以上时间能见度低于200 m。六盘山气象站的雾生消迅速,强浓雾持续时间较长,逆温层厚度增厚早于强浓雾出现的时间,垂直发展深厚,雾发展成熟时逆温层厚度达到1130 m,隆德气象站随着雾发展逆温层厚度也有增厚,但远远小于六盘山气象站,而六盘山气象站逆温强度弱于隆德气象站。随着雾的发展,相对湿度存在明显的向上延伸现象,90%以上相对湿度延伸到1040 m,同时六盘山气象站在出现强浓雾时隆德气象站微波辐射计能够观测到600 m左右的饱和区,这对分析六盘山区典型高山雾垂直演变具有重要意义。

Based on the routine observation data of ground visibility,temperature,relative humidity,wind and other meteorological stations in Longde,Jingyuan and Liupan Mountain Meteorological Station obtained from the observation of mountain fog in Liupan Mountain,northwest China in 2020,and the vertical observation data of microwave radiometer temperature and relative humidity,the circulation situation and the vertical evolution characteristics of temperature and humidity in Liupan Mountain were preliminarily analyzed when the fog occurred in a large range and only at the top of the mountain.The results show that both the large-scale fog process and the mountaintop fog process in Liupan Mountain areas are caused by the warm and humid air flow in front of the trough and the cooling and humidification.The relative humidity on the ground during the two types of fog is more than 95%,mainly southerly winds.The visibility of Longde and Jingyuan Meteorological Stations is more than 200 m,and the visibility of Liupan Mountain Meteorological Station is less than 200 m for more than half of the time;The fog at Liupan Mountain is generated and dissipated rapidly,and the strong fog lasts for a long time.The thickness of inversion layer thickens earlier than the time of strong fog,when the fog is mature,the thickness of the inversion layer reaches 1130 m,with the development of fog,the thickness of inversion layer at Longde Meteorological Station has also increased,but it is far less than that at Liupan Mountain Meteorological Station,and the intensity of inversion at Liupan Mountain Meteorological Station is weaker than that at Longde Meteorological Station.With the development of fog,the relative humidity has an obvious upward extension phenomenon,with more than 90%of the relative humidity extending to 1040 m,at the same time,the microwave radiometer of Longde Meteorological Station can observe a saturated area of about 600 m when there is strong fog at Liupan Mountain Meteorological Station,which is of great significance to analyze the vertical evolution of typical mountain fog in Liupan Mountain.