基于飞机和MODIS观测的华北地区气溶胶标高分析

为研究华北地区的气溶胶分布情况,利用2012—2014年飞机观测资料和MODIS卫星资料,对石家庄等地的气溶胶标高进行了分析。结果表明:(1)与飞机观测资料对比后认为可以利用MODIS光学厚度和常规能见度资料计算气溶胶标高;(2)华北地区春夏季气溶胶标高一般大于秋冬季;6个主要城市中,位于平原地区的城市气溶胶标高较低,西北山区城市标高较高;(3)在不进行飞行探测,仅使用地面资料和卫星资料,通过计算得到气溶胶垂直分布是可行的,尤其是在对流层中层的结果比底层更可信;(4)分别使用观测资料与拟合数据计算光学厚度,分析其误差后,确认在计算光学厚度的过程中可以使用气溶胶数密度指数递减假设。

Analysis on aerosol scale height based on aircraft observation and MODIS products over North China

In order to study the aerosol distribution of North China, the aerosol scale height over Shijiazhuang area was analyzed based on MODIS and the aircraft aerosol observation data during 2012 to 2014. Results show that: (1) the comparison with the aircraft observation data indicated that the MODIS AOD and the conventional visibility data can be used to calculate the aerosol scale height; (2) the aerosol scale heights in North China are generally greater in spring and summer than in autumn and winter. Aerosol scale heights of cities located in plain areas are lower, while cities located in Northwest mountainous regions are higher; (3) it is feasible to obtain aerosol vertical distribution only through the ground data and satellite product but without aircraft observation, especially more credible in middle troposphere than in lower troposphere; (4) through calculating the optical thickness by observational data and fitting data, and then analyzing the error, it is proved that the exponential decline hypothesis of aerosol number density can be applied to calculate optical thickness.