利用常规观测资料、NCEP/NCAR再分析资料,分析2021年12月14~16日山东一次持续性大雾过程的天气形势、气象要素特征以及生消机制等。结果表明:本次过程发生在纬向环流背景下,大雾经历了平流辐射雾–辐射雾–锋面雾的演变阶段。在淄博站...利用常规观测资料、NCEP/NCAR再分析资料,分析2021年12月14~16日山东一次持续性大雾过程的天气形势、气象要素特征以及生消机制等。结果表明:本次过程发生在纬向环流背景下,大雾经历了平流辐射雾–辐射雾–锋面雾的演变阶段。在淄博站大雾维持期间,地面相对湿度多在90%以上,风速在1 m/s左右。前期低层西南暖湿气流和16日早晨近地层弱冷空气前沿的水汽辐合为大雾的形成和维持提供了良好的水汽条件。此次过程具有较明显的辐射雾特征,夜间地面辐射冷却对大雾的形成和加强起了重要作用。逆温强度的增强有利于近地面水汽积聚和大雾加强。两次低层“干性”短波槽活动在大雾形成、发展的不同阶段都起到重要作用。冷空气的影响使低层水汽减少,近地逆温层被破坏,大雾消散。Based on the conventional observation data and NCEP/NCAR reanalysis data, the weather situation, meteorological element characteristics, and formation and dissipation mechanism of a sustained fog process that occurred in Shandong Province from 14 to 16 December 2021 are analyzed. The results show that the fog occurred under the zonal circulation background, and the fog experienced the evolution stage of advective radiation fog-radiation fog-frontal fog. During the maintenance of fog at Zibo Station, the surface relative humidity is more than 90%, and the wind speed is about 1 m/s. The southwest warm and wet flow at low layers in the early phase and the water vapor convergence in the front of the weak cold air near the surface in the morning of 16 December 2021 provided good water vapor conditions for the formation and maintenance of the fog. This process has obvious characteristics of radiation fog, and the ground radiation cooling at night plays an important role in the formation and enhancement of fog. The enhancement of the intensity of the temperature inversion is conducive to the accumulation of water vapor near the surface and the enhancement of the intensity of fog. The influence of cold air reduces water vapor at lower layers, destroys the temperature inversion layer near the surface, and dissipates the fog.展开更多
为了提高对黄渤海海雾天气海面大气水平能见度(以下简称“能见度”)的数值预报能力,利用黄渤海23个沿岸和岛屿测站2013—2017年雾天的地面观测数据,构建了基于湿度信息的能见度算法(A-F算法),并将之应用于黄渤海海雾的能见度数值预报。...为了提高对黄渤海海雾天气海面大气水平能见度(以下简称“能见度”)的数值预报能力,利用黄渤海23个沿岸和岛屿测站2013—2017年雾天的地面观测数据,构建了基于湿度信息的能见度算法(A-F算法),并将之应用于黄渤海海雾的能见度数值预报。结果表明,与常用的根据模式预报的云水含量诊断能见度的SW算法(Stoelinga and Warner,1999)相比,A-F算法表现更优,尤其可以诊断出被SW算法漏报的能见度为1~3 km的轻雾,说明A-F算法对黄渤海海雾天气能见度的数值预报具有一定应用价值。若将来加入浮标与船舶观测数据,可以进一步改进A-F算法能见度公式的具体形式;依据本文构建A-F算法的思路,可以发展适合其他海域的海雾天气能见度诊断公式。展开更多
文摘利用常规观测资料、NCEP/NCAR再分析资料,分析2021年12月14~16日山东一次持续性大雾过程的天气形势、气象要素特征以及生消机制等。结果表明:本次过程发生在纬向环流背景下,大雾经历了平流辐射雾–辐射雾–锋面雾的演变阶段。在淄博站大雾维持期间,地面相对湿度多在90%以上,风速在1 m/s左右。前期低层西南暖湿气流和16日早晨近地层弱冷空气前沿的水汽辐合为大雾的形成和维持提供了良好的水汽条件。此次过程具有较明显的辐射雾特征,夜间地面辐射冷却对大雾的形成和加强起了重要作用。逆温强度的增强有利于近地面水汽积聚和大雾加强。两次低层“干性”短波槽活动在大雾形成、发展的不同阶段都起到重要作用。冷空气的影响使低层水汽减少,近地逆温层被破坏,大雾消散。Based on the conventional observation data and NCEP/NCAR reanalysis data, the weather situation, meteorological element characteristics, and formation and dissipation mechanism of a sustained fog process that occurred in Shandong Province from 14 to 16 December 2021 are analyzed. The results show that the fog occurred under the zonal circulation background, and the fog experienced the evolution stage of advective radiation fog-radiation fog-frontal fog. During the maintenance of fog at Zibo Station, the surface relative humidity is more than 90%, and the wind speed is about 1 m/s. The southwest warm and wet flow at low layers in the early phase and the water vapor convergence in the front of the weak cold air near the surface in the morning of 16 December 2021 provided good water vapor conditions for the formation and maintenance of the fog. This process has obvious characteristics of radiation fog, and the ground radiation cooling at night plays an important role in the formation and enhancement of fog. The enhancement of the intensity of the temperature inversion is conducive to the accumulation of water vapor near the surface and the enhancement of the intensity of fog. The influence of cold air reduces water vapor at lower layers, destroys the temperature inversion layer near the surface, and dissipates the fog.
文摘为了提高对黄渤海海雾天气海面大气水平能见度(以下简称“能见度”)的数值预报能力,利用黄渤海23个沿岸和岛屿测站2013—2017年雾天的地面观测数据,构建了基于湿度信息的能见度算法(A-F算法),并将之应用于黄渤海海雾的能见度数值预报。结果表明,与常用的根据模式预报的云水含量诊断能见度的SW算法(Stoelinga and Warner,1999)相比,A-F算法表现更优,尤其可以诊断出被SW算法漏报的能见度为1~3 km的轻雾,说明A-F算法对黄渤海海雾天气能见度的数值预报具有一定应用价值。若将来加入浮标与船舶观测数据,可以进一步改进A-F算法能见度公式的具体形式;依据本文构建A-F算法的思路,可以发展适合其他海域的海雾天气能见度诊断公式。
