2012年山西省一次大范围持续大雾天气过程分析

Analysis of a Widespread Durative Heavy / Fog Process of Shanxi Province in 2012

利用自动气象站监测资料和常规气象观测资料，对2012年12月14—16日山西大范围持续性浓雾天气过程从天气背景、气象要素特征和物理机制等方面进行了诊断分析，结果表明：此次浓雾是在高空平直纬向环流和地面河套倒槽稳定的天气背景下形成的。湿度增大（减小）对应能见度下降（上升）；近地层大气逆温结构的建立（消失）与浓雾的发生（消散）关系密切；在雾增浓过程中，高湿条件的维持主要依赖于850hPa水汽的输送及近地面水汽的饱和，近地面弱的辐合与低空的弱辐散。

Based on the data of automatic meteorological observation station and conventional weather observation, a heavy fog process during December 14 - 16 in Shanxiwas diagnostically analyzed from weather background, meteorological elements characteristics and physical mechanism. The result showed that： the heavy fog Occurred under the straight zonal circulation and the stable surface inverted trough over Hetao area. The humidity had a negative correlation with visibility. The temperature inversion near the surface had close relations with the heavy fog. The maintenance of high humidity mainly relied on the water vapor transport at 850hPa, the water vapor saturation and the weak convergence near the surface, and the weak divergence of low - level.