多波段激光雷达颗粒物质量浓度探测方法

摘要

为了获得大气颗粒物的质量浓度廓线,提出一种基于多波段激光雷达回波信号的大气气溶胶消光系数与颗粒物质量消光效率相结合的新型算法.该方法利用覆盖紫外到近红外波段的激光雷达作为遥感探测工具,获取气溶胶的消光与后向散射系数,反演得到气溶胶粒子谱分布;同时,根据米散射理论算出气溶胶消光效率,结合粒子谱分布,提出颗粒物质量消光效率模型,从而建立基于消光系数与质量消光效率相结合的反演颗粒物质量浓度的新型数学模型与算法.采用该算法对两组不同天气条件多波段激光雷达实测数据进行反演,并与地表采用的颗粒物浓度对比,证明该方法的可行性,为实现颗粒物质量浓度空间分布的探测提供科学依据和方法论.%A novel method for particulate matter mass concentration measurement has been proposed based on a multi-wavelength lidar covering the ultraviolet to the near infrared spectra.The proposed method combined extinction coefficients at working wavelengths with quantity of mass extinction efficiency(MEE),which is defined as the ratio of extinction coefficient and mass concentration of particulate matter in unit volume,makes the mass concentration of particulate matter retrievable.To determine the values of the MEE,a mathematical model was developed based on the extinction efficiency data of certain wavelength repor-ted with the Mie theory and the particle size distribution data derived from a multi-wavelength lidar.Retrieved results of mass concentration from two experimental cases with clear and fog/haze weather conditions,which s in line with the monitoring re-sults at the ground level reported by the Environmental Agency.The proposed method invert the recent problem on aerosol sources monitoring and open new lidar capabilities on atmospheric research.