【摘要】 选取气溶胶自动观测网(AERONET)北京站和香河站2006-2017年第3版的数据,对比气溶胶光学厚度(AOD)、波长指数A_E、可降水量、单次散射反照率、气溶胶散射光学厚度、气溶胶吸收光学厚度、激光雷达比L_R、退偏比D_R和球形分数SF的季节变化与日变化.香河站的AOD、A_E和可降水量均大于北京站,两站在气溶胶吸收特性上表现出夏季北京站大于香河站.受沙尘影响,两站春季L_R<60 sr,其他季节均大于60 sr,表现为人为污染和生物质燃烧气溶胶主导. D_R在春季最高,夏季和冬季较小,除五月外,北京站的D_R均大于香河站. S_F在春季为20%～40%,其他季节>50%,且北京站的S_F均小于香河站.在A_E、D_R、S_F的日变化中观察到明显具有城乡差异的交通早高峰影响.北京地区在早高峰时段的气溶胶颗粒更大且非球形程度更高,反映出北京市区在早高峰时段会产生更多的机动车扬尘气溶胶.更多还原

【Abstract】 The paper selected the Version 3 data of aerosol robotic network(AERONET) in the Beijing and Xianghe site from 2006 to 2017, and compares seasonal and daily trends in aerosol optical depth(AOD), angstrom exponent(A_E), precipitable water, single scattering albedo, aerosol scattering optical depth, aerosol absorption optical depth, lidar ratio(L_R), depolarization ratio(D_R), and spherical fraction(S_F). The AOD, A_E and precipitable water of the Xianghe site were larger than those of Beijing site. The absorption characteristics showed that the Beijing site was larger than the Xianghe site in summer. Affected by dust, the L_R of the two sites was lower than 60 sr in spring, and in other seasons it was more than 60 sr,and was dominated by anthropogenic pollution and biomass burning aerosol. D_R was the highest in spring and small in summer and winter. Except for May, the D_R of Beijing site was larger than that of Xianghe site. S_F was 20% to 40% in spring and more than 50% in other seasons, and the S_F at Beijing site was smaller than Xianghe site. Obvious morning peaks with significant urban and rural differences were observed in the daily trends of A_E, D_R, and S_F. The size of aerosol particles in the Beijing area were larger and more non-spherical at the early peak hours, indicating that the Beijing area would generate more vehicle dust aerosols during the morning rush hour.更多还原