长江三角洲地区大气污染物输送规律研究

采用NCEP全球再分析资料运行MM5获得研究区域2004年代表月份的气象场模拟结果,运用HYSPLIT4.8模式,计算代表城市的后向及前向气流轨迹.结果表明,不同季节,气流轨迹的分布差异明显,影响范围各不相同.影响长三角地区低层大气的输送气流主要来源于蒙古、华北或东北地区,途径黄海海域或东部沿海的山东、江苏或上海等地抵达长三角地区.受夏季西南季风的影响,西南方向也是比较重要的输送途径.长江三角洲地区对外界的中尺度污染传输主要受东亚季风活动的影响,其中冬季季风是长三角污染物向华南和西太平洋地区传输的一个主要机制;影响长三角污染物输送的重要系统还包括春夏控制我国东部沿海地区的西太平洋副热带反气旋环流,该系统主要向西影响我国内陆地区.

Transport Characteristics of Air Pollutants over the Yangtze Delta

Meteorological field of January, April, July and October in 2004 was obtained by running MM5 with NCEP datasets. Then we used HYSPLIT 4.8 model to calculate the backward and forward trajectories of representative cities. Distributions of trajectories and the affected areas vary with seasons. Transport current affecting Yangtze River Delta is mainly from Mongolia, North China or Northeast region, via Yellow Sea area, Shandong, Jiangsu province or Shanghai. Another important transport path is current from southwest because of the Southwest monsoon. A movement of East Asia monsoon plays an important part in the mesoscale transport of pollutants in Yangtze Delta. Winter monsoon is a main mechanism which moves the air pollutants in Yangtze Delta to South China and West Pacific ocean. Another important transport system is the subtropical anticyclone over the western Pacific Ocean which controls the east coast of our country in spring and summer. This circulation system mainly affects the inland area of our country.