气象与环境学报2011，Vol.27Issue(1)：35-39,5.
华北南部一次回流暴雪天气的诊断分析
Diagnostic analysis of a heavy snow of return-flow event in North China
摘要
Abstract
Based on the conventional observational data and the NCEP reanalysis data,the dynamic and thermodynamic characteristics of a heavy snow of return-flow event in the southern part of North China were analyzed.The results indicate that synoptic situation of this process is two troughs and one ridge.The influencing system leading to the heavy snow of return-flow event includes high level jet,westerly trough,low vortex shear and low level jet,and cold air in Northeast China triggers this event.The maximum precipitation occurs just at the changing period of southerly wind and northerly wind.Precipitation ends when northeasterly wind controls entirely the low level.The stacking of high level divergence and low level convergence, subsidence of positive vorticity in the high level causes strong precipitation, while the ascending movement center is fairly low.Warming and humidifying before snowfall and insertion of cold air in the low level make the south of North China locating in energy front area of θse and water vapor convergence area, which is benefit to the generation of heavy snow.Water vapor of return-flow event is mainly from the south, and it is transported indirectly by cold air from Northeast China in low level.关键词
回流暴雪/急流/诊断分析Key words
Heavy snow of return-flow event/ Jet stream/ Diagnostic analysis分类
天文与地球科学引用本文复制引用
田秀霞,宋晓辉,程序,董占强,李菊香,聂振岭..华北南部一次回流暴雪天气的诊断分析[J].气象与环境学报,2011,27(1):35-39,5.基金项目
国家自然科学基金项目(40875024)和河北省自然科学基金项目(D2008001282)共同资助. （40875024）
