成都双流机场两次辐射雾发展过程对比分析

Comparative Analysis of Two Evolution Processes of Radiation Fog at Chengdu Shuangliu International Airport

摘要: 利用成都双流机场自动观测系统资料，对2023年1月5日和3月3日两次辐射雾过程进行对比分析。两次过程环流背景相似，均为高空槽快速东移后夜间转晴、辐射降温导致地面饱和，但两条跑道端(02L、02R)能见度差异显著：1月5日两端均出现浓雾，最低能见度150 m；3月3日仅02R端起雾，02L端能见度维持在1000 m以上。结果表明，起雾端气温稳步下降、相对湿度波动上升至97%以上，未起雾端气温下降缓慢；起雾端风速较小(1.0 m/s以下)、水平湍流动能较低(0.2 m²/s²以下)，但湍流强度偏大，未起雾端风速偏大(最大2.1 m/s)、水平湍流动能较高(达0.6 m²/s²)而湍流强度偏小。利用机场地面风资料计算的湍流动能和湍流强度对辐射雾临近预报具有一定参考价值。

Abstract: Based on automatic observation data of Chengdu Shuangliu International Airport, compare two radiation fog events on January 5 and March 3, 2023. Both events occurred under similar circulation conditions: clear nights after the rapid eastward shift of upper-level troughs, where radiative cooling led to surface air saturation. However, visibility varied significantly between the 02L and 02R runway thresholds. Dense fog affected both runways on January 5, with a minimum visibility of 150 m, while fog only occurred at the 02R threshold on March 3, and the visibility at the 02L threshold remained above 1000 m. The results show that fog-prone areas experienced steady temperature drops and fluctuating relative humidity rising above 97%, whereas temperature decreased slowly in fog-free areas. At foggy runway ends, the wind speed was below 1.0 m/s and horizontal turbulent kinetic energy was less than 0.2 m²/s², with relatively high turbulence intensity. In contrast, fog-free runway ends had a maximum wind speed of 2.1 m/s and higher horizontal turbulent kinetic energy up to 0.6 m²/s², but lower turbulence intensity. Turbulent kinetic energy and turbulence intensity calculated from airport surface wind data can provide references for the nowcasting of radiation fog.