气象学报Issue(6)：1039-1051,13.DOI:10.11676/qxxb2015.082
一次入海气旋局地暴雪的结构演变及成因观测分析
Case study of the cause and the dynamic structure for a small-scale snowstorm event associated with a cyclone
摘要
Abstract
This study investigates the cause and the dynamic structure on a small-scale snowstorm event occurred in the Shan-dong peninsula with the Doppler radar,profile,automatic station,routine sounding and surface observation data.the results are as follows:(1)Precipitation occurred in the two stages:the first weak precipitation one was typical snowstorm caused by the Huanghe cyclone with the characteristic of weak snowfall and north-east radar echo,and the second strong precipitation one behind the cyclone was ocean-effect snowstorm with the characteristic of strong snowfall and south-west radar echo.(2)Favor-able synoptic situation led to the occurrence of the first stage snow,such as the obvious trough,cyclonic circulation,south-western low-level jet and surface cyclone.Its vapor came from the South China Sea.The snowfall was distributed to ahead of southwestern low-level jet on the right and eastern side of the surface cyclone.(3)By contrast,the second precipitation stage occurred after the trough passed the Shandong peninsula and the cyclone passed through the Bohai straight to the Huanghai Sea.Cold air intruded into the Shandong peninsula from the Bohai straight and the Huanghai Sea.North-east wind was prevail-ing and its speed was stronger than the north-west wind,which brought rich water vapor and heat.Snowfall distributed within north-east wind.And,(4)the structure of wind field in the lower troposphere was different during the ocean-effect snowstorm. At the beginning,there was a mid-γscale low circulation beside the north coastal area in the Shandong peninsula,and radar ra-dial velocity shows a meso-βvortex in low level.Meanwhile,there was a shear between the south-east wind and north-west wind near the east coastal area.During the strong snowfall,a shear between the north-east and north-west wind was found in the boundary layer.Both the low circulation and shear are the favorable dynamic factors.As a result,the case implies that re-markable difference between the Bohai strait/Huanghai Sea and the Bohai Sea ocean-effect snowstorm,the former is behind the Huanghe cyclone,and the latter is common and typical,in terms of the wind field structure,motion of radar echo and precipi-tation distribution.关键词
黄河气旋/暴雪/海效应/观测数据分析Key words
Huanghe River cyclone/Snowstorm/Ocean-effect/Analysis of observation data分类
天文与地球科学引用本文复制引用
杨成芳,周淑玲,刘畅,郭俊建,杨璐瑛..一次入海气旋局地暴雪的结构演变及成因观测分析[J].气象学报,2015,(6):1039-1051,13.基金项目
资助课题国家自然科学基金（41175044、41475038）、中国气象局关键技术集成与应用项目（CMAGJ2015M34）、中国气象局预报员专项（CMAYBY2015-041）、山东省气象局重点课题（2013sdqxz02）。 （）
