联网激光雷达的观测性能综合平行比对

激光雷达以其高精度的探测能力在大气污染研究中得到了广泛应用。由于生产厂家和反演算法等的差异,激光雷达观测数据的质量参差不齐。笔者利用2013年11月和2014年3月2种不同型号激光雷达(高频激光雷达和微脉冲激光雷达) 532 nm波段的气溶胶消光系数和气溶胶自动观测网(AERONET)光学厚度数据,对2部雷达在不同空气质量下的观测性能进行综合对比。结果表明:2部雷达在不同空气质量条件下探测效果不同,空气质量为优和良时,2部雷达的消光系数比较一致,偏差主要在1 km以下;随着污染加剧,2部雷达在1 km以下的偏差先减小后增大,1 km以上的偏差随高度增大。与AERONET的光学厚度相比,高频激光雷达在轻度污染和严重污染时相对误差较小(3. 23%和26. 75%);微脉冲激光雷达在良和轻度污染时相对误差较小(40. 00%和25. 81%)。2部雷达设备的差异和重污染时不利的气象条件是影响雷达表现的重要原因。该研究作为全国激光雷达联网的前期工作,为全国激光雷达数据的综合应用提供了参考。

Comprehensive Parallel Comparison of Observational Performance of Connected Lidars

Lidar has been widely used in air quality researches for its high precision detection capability.However,the quality of observational data varies due to differences of lidar manufacturers and inversion algorithm used.As a pre-research of establishing the national lidar network,the characteristics of optical parameters were comprehensively compared based on two lidars (high-frequency lidar and micro-pulse lidar) 532nm aerosol extinction coefficients and aerosol robotic network (AERONET) aerosol optical thickness (AOD) in November 2013 and March 2014.The results showed that two lidars performed diversely under different air quality levels.When the air quality was excellent and good,extinction coefficients of two lidars were relatively uniform.And the bias between two lidars were mainly below 1km.However,the bias decreased first and then increased below 1km and the bias increased with height layer above 1 km with the aggravation of air quality.Compared with AOD of AERONET,the relative errors of high-frequency lidar were smaller in lightly and severely polluted days (3.23% and 26.75%);the relative errors of the micro-pulse lidar was smaller in good and lightly polluted days (40.00% and 25.81%).The instrument differences and adverse meteorological conditions during heavy pollution may contribute a lot to the differences between two lidars.This paper would provide references for the comprehensive application of national lidar data.