Evolution of Aerosols Near The Surface at AERU on The Southwestern Japan Coast in 2010-2015
作者单位：Faculty of Environmental and Symbiotic Sciences Prefectural University of Kumamoto School of Environmental Studies Nagoya University Graduate School of Science Tohoku University
会议名称：《第十八届中国科协年会——分12 大气雾霾及PM2.5控制先进技术研讨会》
会议日期：2016年
学科分类：07[理学] 070602[理学-大气物理学与大气环境] 0706[理学-大气科学]
关 键 词：Lidar humidity sea salt dust soot
摘 要：We observed the concentration and backscattering coefficients of aerosol particles at southwestern coast of Japan in 2011-2015. The constitution of particles in each of eight episodes, i.e. the portions of mineral dust, sea salt, sulfate and soot particles, was obtained with individual particle analysis by using an electron microscope. There was a close correlation(R2=0.76) between the BSCs and the volume concentrations of the particles when the relative humidity(RH) was lower than 0%, regardless of the difference in particle constitutions. In contrast, the BSCs normalized with aerosol concentrations differed largely even at similar concentrations of particles when the RH was larger than 70%. The BSCs of particles dominated by marine origin(sea salt) could be several times larger than those dominated by land origin(dust and soot) at 90% RH, as the latter might be slightly larger than the BSCs under the dry conditions. On the other hand, the difference of volume-size distributions of particles likely also made the BSCs largely different from each other under the humid conditions. These results indicate that the concentration of aerosol particle was the key parameter to determine the BSCs under dry conditions, while the BSCs under humid conditions were closely dependent on the content of deliquescent components and the size distributions of aerosol particles.