北京及华北平原边界层大气中污染物的汇聚系统--边界层输送汇

由地面、3个大气压风带(1000,925,850hPa)、气压场、温湿廓线、能见度、暖湿平流以及激光雷达,航测分析,提出太行山山前、燕山山前输送汇。输送汇及其摆动常造成华北平原及北京地区区域大气污染物汇聚,是形成重污染区的主要形式。输送汇配置各类风向风带区,冬秋季节多为区域性短而浅的边界层输送风带,夏季多为天气尺度型的、远而厚的边界层输送风带。弱气压场或均压场背景下地方性山风及山前串状城市热岛群形成的热力性、动力性低压环流,是输送汇形成的主要原因。 

Convergence System of Air Contamination in Boundary Layer above Beijingand North China:Transportation Convergence in Boundary Layer

The transportation convergence in front of Taihang Mountain and Yan Mountain was proposed according to the ground,(1　000),925 and 850 hPa wind belt and the field of pressure,the wet-warm profile,Lidar data,visibility,warm-wet advection air and airborne analysis.Transportation convergence,which formed the pollution of North China and Beijing region,was a major model that formed a severe pollution area.The transportation convergence was disposed on various wind belts,which were short and shallow transport wind belts of the boundary layer in the autumn and winter,and long and deep transport wind belts of the boundary layer of weather scales in the summer.The local valley wind and the group of the thermal series islands,and thermal and dynamical circulation of the low pressure under the background of the weak pressure and average pressure fields were the major causes of forming the transportation convergence.