于2006年12月14日-2007年4月31日在兰州大学半干旱气候与环境观测站,架设了CE318光度计和CE-370-2型激光雷达,选取半干旱区晴天无云条件下同期观测的激光雷达和太阳光度计数据,分析了激光雷达采用不同k值反演的气溶胶消光系数随高度的变化及垂直分布趋势.结合两种仪器反演的光学厚度值的差异性,对K1ett法求解雷达方程时k的取值进行了深入研究.结果表明,半干旱地区对激光雷达观测所获取数据采用Klett算法反演气溶胶消光系数时,参数k的确定在计算中极为关键,对结果的影响不可忽视;在半干旱区k取值0.78~0.80较为合理,取值0.78更为精确.
The CE318 sun photometer and CE-370-2 laser radar were erected at the semi-add climate and envi- ronmental observation station in Lanzhou University from December 14, 2006 to April 31, 2007. Based on the same-period observation data from laser radar and sun photometers under sunny and cloudless conditions, the changing values with the height and vertical distribution trend of the aerosol extinction coefficients were ana- lyzed, which were inverted when the laser radar used different k values. Combined with the differences be- tween the optical thickness values from the two kinds of instruments, the selection ofk values were further stud- ied to solve the radar equation with the Klett method. The results showed that the values of the parameter k are critically important in the calculation process and cannot be ignored in considering the impact on the results when the laser radar observation data are used to invert the aerosol extinction coefficient with the Klett algo- rithm. In a semiarid region, the k with a range value from 0.78 to 0.80 is relatively reasonable and that with a value of 0.78 is more accurate.