【作者】 高星星； 陈艳； 张镭； 张武； 鲁澎学；

【Author】 GAO Xing-xing;CHEN Yan;ZHANG Lei;ZHANG Wu;Key Laboratory of Semi-Arid Climate Changes with the Ministry of Education, College of Atmospheric Sciences, Lanzhou University;

【机构】 兰州大学大气科学学院半干旱气候变化教育部重点实验室； 甘肃省金昌市气象局；

【摘要】 为研究高污染地区气溶胶形成机理提供理论依据,利用CALIPSO卫星2级产品,分析了华北地区不同污染条件下气溶胶光学厚度(AOD)的时空分布特征,气溶胶的季节成分比例及其光学属性和垂直分布特征,并结合AERONET观测数据,对气溶胶的季节光学属性进行了验证.结果表明:华北地区AOD高值区分布于海拔较低平原地带,而低值区主要位于海拔较高的山地丘陵;夏季AOD值最大,春季最小;能见度大时,AOD小,而能见度小时,AOD大;华北地区AOD近十年间呈现微弱的上升趋势,趋势值为0.003;华北地区气溶胶以人类活动产生的气溶胶为主,但在春季,秋季,冬季受到来自北方沙尘的影响显著;春季退偏振比(PDR)和色比(CR)值最大,夏季最小;春季沙尘被长距离传输到了对流层中部及其以上区域,夏季强烈的垂直对流活动使得大量的气溶胶被从边界层内带到了自由对流层,秋冬季节稳定的气象条件使得大量的气溶胶滞留在边界层内.更多还原

【Abstract】 To provide theoretical basis for studying the formation mechanism of aerosol, this paper analyzes the spatial and temporal variation characteristics of the aerosol optical depth and the season aerosol composition, optical properties and vertical distribution under different polluted conditions over North China by using Level 2 products provided by CALIPSO system. The season aerosol optical properties are validated by the AERONET observation data. The results show that the high AOD is at the plain regions with the lower elevation while the low AOD is at mountains and hills with the higher elevation, AOD in summer is the highest while AOD in spring is lowest, and that AOD reaches the minimum when the visibility is in the maximum and vice versa. The temporal variation of AOD during the nearly 10 years shows that there is a weak overall upward trend over North China and the trend is 0.003. The aerosols generated by human activities dominate over North China while the dust from the north dominate in spring, autumn and winter. The particulate depolarization ratio and the color ratio are largest in spring and smallest in summer. The dust is transported to the middle and upper troposphere in spring, the strong vertical convection activities in summer transport massive aerosols from the atmospheric boundary layer to the free troposphere, and the stable meteorological conditions in autumn and winter trap massive aerosols within the boundary layer.更多还原