基于CALIPSO卫星资料的华东地区气溶胶垂直分布特征

基于2010年12月1日—2011年11月30日美国国家航空航天局云—气溶胶激光雷达与红外探测者卫星搭载的激光雷达CALIPSO的监测数据,通过分析消光后向散射系数、体积退偏比和色比,得到了华东地区垂直方向上气溶胶粒子的散射能力、尺度、规则程度随高度的变化及其季节变化特征。结果表明:随着高度的增加华东地区大气的散射能力减弱。整层大气不同季节粒子的形状大小不同,春季不规则、大粒径粒子所占比例与其他季节相比较大。夏季较规则、小粒径的粒子较多。各高度层的后向散射系数值分布范围为5×10-4~20×10-4 km-1·sr-1。对不同高度消光后向散射系数、体积退偏比和色比随时间变化的研究表明,春季受沙尘输送的影响,0~4 km大气层中不规则大粒径粒子较多;4~8 km大气层由于所含气溶胶粒子较少,大气散射能力随季节变化不明显;而8~10 km大气层中粒子含量最少,导致大粒径粒子所占比例较高,此外该高度层在秋季不规则、大粒径粒子相对较多,冬季规则、小粒径粒子相对较多。

The characteristic of aerosol vertical distribution in Eastern China based on CALIPSO satellite data

The characteristics of the vertical distribution and the seasonal variation of the scattering capacity, size scale, and regular degree of aerosols in Eastern China from December 1, 2010 to November 30, 2011 were explored based on the aerosol products, such as the total attenuated backscatter coefficient (ABC), volume depolarization ratio (VDR), and color ratio (CR), obtained by the Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) of NASA. The results showed that the atmospheric scattering decreased with height. The shapes and sizes of aerosols varied in different seasons. The ratio of relatively more irregular and larger particles was higher in spring than that in the other seasons in the atmosphere. However, the ratio of relatively more regular and smaller particles was largest in summer. The attenuated backscattering coefficients ranged from 5×10-4 to 20×10-4 km-1·sr-1 in each level. The change of ABC, VDR and CR in spring showed that there existed relatively more irregular and larger particles in the level of 0-4km above ground, due to the influence of dust transport. In the level of 4-8 km, the seasonal variation of the atmospheric scattering was not obvious due to little aerosol particles existed in this level. In the level of 8-10 km, the fraction of relatively larger particles was relatively higher because of the lowest aerosol loading in this level. Additionally, the amount of relatively more irregular and larger particles was more in autumn than that in the other seasons, while the amount of relatively more regular and smaller particles was more in winter in this level.