基于激光雷达和微波辐射计的气溶胶质量浓度反演算法研究与分析  

Aerosol Mass Concentration Retrieval Algorithm Based on LiDAR and Microwave Radiometry

作　　者：季承荔[1,2] 陈臻懿 黄艺峰 茆佳佳[1] 王志成[1] 古锐昌 刘爱明[4] 张春生 项衍 Ji Chengli;Chen Zhenyi;Huang Yifeng;Mao Jiajia;Wang Zhicheng;Gu Ruichang;Liu Aiming;Zhang Chunsheng;Xiang Yan(CMA Meteorological Observation Centre,Beijing 100081,China;CMA Meteorological Observation Engineering Technology Research Center,Beijing 100081,China;School of Light Industry Science and Engineering,Beijing Technology and Business University,Beijing 100048,China;Shenzhen National Climate Observatory,Shenzhen 518040,Guangdong,China;Institute of Physical Science and Information Technology,Anhui University,Hefei 230601,Anhui,China)

机构地区：[1]中国气象局气象探测中心,北京100081 [2]中国气象局气象探测工程技术研究中心,北京100081 [3]北京工商大学轻工科学与工程学院,北京100048 [4]深圳市国家气候观象台,广东深圳518040 [5]安徽大学物质科学与信息技术研究院,安徽合肥230601

出　　处：《中国激光》2024年第5期196-205,共10页Chinese Journal of Lasers

基　　金：中国气象局创新发展专项(CXFZ2024J011,CXFZ2024J057);民用航天技术预先研究项目(D020305);中国科学院环境光学与技术重点实验室开放基金(2005DP173065-2021-07)。

摘　　要：大气气溶胶是重要的大气污染物之一,气溶胶质量浓度的垂直分布及其与气象要素的相互影响,对理解大气污染传输具有重要意义。激光雷达因具有高时空分辨率的探测优势而成为研究气溶胶颗粒物立体分布的有力工具。本文利用深圳米散射激光雷达、微波辐射计和近地面气溶胶质量浓度监测仪,根据均方差选取最优参数,建立基于消光系数的温湿融合PM_(2.5)质量浓度反演模型,并以深圳气象梯度观测塔4个高度的PM_(2.5)质量浓度小时均值为基准,对模拟结果进行了验证分析。结果显示:模拟值与观测值两者的变化趋势一致性较好,相关系数受模拟高度、相对湿度影响,并进行了晴天、多云天气下的比对,深圳气象梯度观测塔上4个高度的模拟值和实测值相关系数均大于0.68,平均绝对误差和均方根误差最大值分别为6.88μg/m^(3)和18.56μg/m^(3)。比较4个季节的模拟效果发现,冬季的模拟结果准确性要低于其他三个季节。最后通过个例分析,结合地面温度、相对湿度、风场和气压场,分析了深圳夏季颗粒物质量浓度的时空分布特征。Objective The technology for retrieving aerosol extinction coefficients from LiDAR is mature.However,further progress is required to retrieve the vertical distribution of aerosol mass concentration.In addition,accuracy evaluation of aerosol mass concentration from LiDAR is challenging owing to the lack of standard vertical PM_(2.5) mass concentration.Therefore,in this study,a PM_(2.5) mass concentration retrieval algorithm was developed by integrating real-time temperature,relative humidity,and extinction coefficient profiles.The PM_(2.5) mass concentration at four heights of the Shenzhen Meteorological Gradient Observation Tower was used as the standard value to evaluate the accuracy of the model under different weather conditions and seasons.Methods The influence of meteorological factors on the vertical distribution of aerosol mass concentration is extremely complex,particularly under precipitation conditions where the LiDAR signal attenuation is severe.Therefore,in this study,only the effects of temperature and relative humidity on the vertical distribution of aerosols under non-precipitation weather conditions were investigated.In practical applications,sample data are initially preprocessed,including the outlier handling(triple standard deviation removal),rainy day data,and missing value removal.The extinction coefficient at the lowest height of the LiDAR,ground temperature,relative humidity from the microwave radiometer,and PM_(2.5) mass concentration near the ground were substituted into an exponential model.The data from 2500 h were subsequently used for model fitting.The model parameters were automatically determined based on the minimum mean square error.Thus,the extinction coefficient,temperature,and relative humidity profiles at a specific height could be selected to calculate the PM_(2.5) mass concentration at the corresponding height.To investigate the accuracy of the PM_(2.5) mass concentration inversion,comparisons were conducted between PM_(2.5) mass concentrations at four heights(70,120,220,and

关 键 词：激光雷达 PM_(2.5)质量浓度 消光系数 

分 类 号：X831[环境科学与工程—环境工程] P412.25[天文地球—大气科学及气象学] P407.5