Analysis of the mechanisms of boundary layer easterly wind and snowstorm over the western coast of the Bohai Sea
Rarely intense snowstorms occur on December 20-21,2008 and January 3,2010 respectively in Tianjin.These two weather processes were analyzed based on multiple data in order to understand the mechanism of this weather.The results indicate that two snowfall events are both backflow-type snowstorms despite synoptic patterns and major weather systems in each case are distinctly different.Main weather systems are the horizontal trough at the upper level,850 hPa shear and surface inverted trough（surface cyclone）.Moreover,southwesterly airflow in 700 hPa provides moisture condition.Two processes are both accompanied by boundary layer easterly wind.The easterly wind not only transports some moisture,but also produces the surface convergence line with the warm and damp southerly wind,which could strengthen the lifting action and could generate lifting motion.Therefore,it is favorable to strengthen and maintain this weather process.Boundary layer easterly wind is playing a significant role in the initiation and development of snowstorm.
国家科技期刊平台
NSTL
万方数据
维普
