贵阳机场近15年冻雾天气特征及一次典型过程分析

Analysis of Freezing Fog Weather Characteristics at Guiyang Airport over the Past 15 Years and a Typical Case Study

摘要: 基于2010~2024年贵阳龙洞堡国际机场观测资料及ERA5再分析数据，通过统计分析与典型过程诊断发现：近15年冻雾年均1.53次，集中于冬季(11月~次年2月)，凌晨始发(平均04:40)上午消散(平均09:55)，持续约5小时15分钟，其中辐射冻雾占比87%，具有始发早、持续久、能见度低的特征；典型过程中，高空脊前西北气流与地面均压场构建静稳环流，近地面至850 hPa深厚逆温层阻断垂直交换，“弱下沉 + 弱辐合”的动力耦合叠加夜间辐射降温，驱动边界层水汽饱和凝结。研究明确了冻雾的时空规律与动力–热力耦合机制，为机场冻雾预报及民航运行保障提供理论支撑。

Abstract: Based on observational data from Guiyang Longdongbao International Airport from 2010 to 2024 and ERA5 reanalysis data, statistical analysis and diagnostic studies of typical processes reveal that over the past 15 years, there have been an average of 1.53 occurrences of freezing fog annually, predominantly during winter (November to February). These events typically begin at around 4:40 AM and dissipate by 9:55 AM, lasting approximately 5 hours and 15 minutes. Among them, radiative freezing fog accounts for 87%, characterized by early onset, prolonged duration, and low visibility. In typical processes, high-altitude ridges with northwest airflow and ground-level isobaric fields create a stable circulation, while a deep temperature inversion layer from near the surface to 850 hPa impedes vertical exchange. The combination of weak subsidence and weak convergence dynamics, coupled with nighttime radiative cooling, drives the saturation and condensation of boundary-layer moisture. This study clarifies the spatiotemporal patterns and dynamic-thermal coupling mechanisms of freezing fog, providing theoretical support for airport freezing fog forecasting and civil aviation operational assurance.