浙江省气溶胶垂直分布及区域传输分析

利用6个激光雷达站点数据从年际和季节变化尺度对浙江省2017~2018年气溶胶垂直分布特征进行研究，并结合污染物浓度数据分析了浙江省主要颗粒物类型的季节差异.结果表明，大部分站点2018年气溶胶消光系数整体小于2017年；边界层内消光系数空间上呈中部高东西低的分布形态；消光系数季节变化表现为冬季最高，秋季其次，而春夏较低；气溶胶在春、夏季集中在地面上方1~2km以内，冬季主要分布在1km以下，秋季受高空气溶胶影响，6个站点呈现出不同的垂直分布模式.进一步，选取发生在2018年4月和7月两次气溶胶跨区域传输过程，综合CALIPSO和MODIS卫星数据、以及后向轨迹、PSCF与CWT模式对污染物来源与传输机制进行探索，发现来自AOD高值区的气团显著加重本地污染.

Vertical distribution and regional transport of aerosols in Zhejiang Province

The interannual and seasonal changes of aerosol vertical distributions in Zhejiang Province from 2017 to 2018 were studied using Micro Pulse Lidar (MPL) measurements in six sites. Air quality data were combined to analyse the dominant particulate matter types in terms of seasonal differences. Aerosol extinction coefficients of most sites in 2018 were lower than that in 2017. Spatially, the extinction coefficient within the boundary layer was high in central Zhejiang and low in the eastern and western Zhejiang. Seasonally, the extinction coefficient was the highest in winter, second in autumn, and lower in spring and summer; aerosols were concentrated within 1~2km above the ground in spring and summer, and mainly distributed below 1km in winter; in autumn, affected by high-altitude aerosols, the six stations showed different vertical distribution patterns. Furthermore, the aerosol sources and transmission mechanisms of two trans-regional transport episodes in April and July 2018 were revealed, by using the CALIPSO and MODIS satellite data, as well as the backward trajectory, PSCF and CWT models. It was found that air masses from high AOD areas can significantly increase local pollution in Zhejiang.