在对2007年10月26日北京大雾天气形势及能见度分析的基础上,利用12通道微波辐射计、风廓线仪及NOAA极轨卫星监测资料与中尺度数值模拟结果,比较研究了雾的分布区域、温度、湿度、风速及液态水含量的边界层分布特征.利用中尺度模式模拟结果探讨了此次大雾的维持和形成机理,具体展现了此次大雾是在稳定大气层结、充沛水汽条件下,地面长波辐射冷却及雾顶的长波辐射冷却降温形成发展的过程,而太阳的短波辐射对雾的减弱消散有重要影响.%On the basis of Analysis of the synoptic situation and the visibility for the heavy fog event on 26 October 2007 in Beijing area, comparative analysis of the fog area, the boundary layer distribution characteristics of the tem-perature, humidity, wind speed, and liquid water content (LWC) is conducted with the observation data of the radi-ometer, wind profiler, satellite, and the simulation results. In addition, the mechanism of the fog formation, main-tenance and dispersal is analyzed with the simulation results of a mesoscale model The results indicate that the long-wave radiation cooling is the important factor of the fog formation in addition to the steady atmospheric stratification and plenty of moisture, while the fog dispersal was most influenced by the shortwave radiation.
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