利用激光雷达探测灰霾天气大气边界层高度

Observation of atmospheric boundary layer height by ground-based LiDAR during haze days

为了探测灰霾天气大气边界层高度变化的特征,利用CE370-C型微脉冲激光雷达观测了北京2013年1月严重灰霾期间的大气边界层高度。基于激光雷达距离校正回波信号,使用梯度法处理了严重灰霾天和轻度灰霾天的大气边界层观测数据,发现在灰霾天气时大气边界层高度显著降低,严重污染时的大气边界层高度低于500m,日平均高度约424m,且与PM2.5浓度呈现明显的负相关性。将激光雷达探测结果与探空数据进行了对比分析,结果显示激光雷达与探空数据观测结果有较好的一致性,两者在本次灰霾期间的平均差异约为86m。

In order to investigate characteristics of atmospheric boundary layer height （ABLH） during haze pollution, we used ground-based CE370-C micro pulse LiDAR to derive the ABLH during January 2013 over Beijing, based on the gradient method. We find that the ABLH in severe haze days is lower than that in weak haze days and beneath about 500 m, with daily averaged value of about 424 m. The ABLH has negative correlation with the concentration of surface PM2.5. The comparison of LiDAR observation with radiosonde detection is also presented in the paper and results show that two approaches have good consistency with difference less than about 86 meters.