Mobile Vehicle Lidar for Urban Air Pollution Monitoring
Atmospheric haze pollution monitoring vehicle.
Spatial distribution of aerosol extinction coefficient.
In recent years, various areas in China have suffered from haze pollution. Face masks are commonly used as protection against this condition, as they limit the inhaling of the airborne particles. Therefore, researchers are making efforts to realize sensitive air pollution monitoring and the corresponding treatment. Lidar technology has been used in the detection of atmospheric pollution. At present, it is mainly applied as fixed lidar and as airborne and spaceborne lidar applicable to a single point or to large areas. However, a lidar system with higher spatial and temporal resolution is required to monitor the time-space distribution and the transport pattern of atmospheric particulate matter at an urban scale. In this regard, the vehicle lidar system can provide superior observation results.
A mobile vehicle lidar system, proposed by the research group of Professor Tianshu Zhang from Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, has been used recently to research urban air pollution. The related research results have been reported in Chinese Optics Letters, Volume 14, No. 6, 2016 (L.H. Lv et al., Application of mobile vehicle lidar for urban air pollution monitoring).
Vehicle lidar technology is based on the Mie scattering theory, which is used to determine the parameters of the aerosol extinction coefficient, depolarization ratio, planetary boundary layer height, and the aerosol optical thickness of the atmosphere with laser. Moreover, it is used to analyze the distribution, transportation, and the source of the pollutants.
In this study, an experiment was carried out in the Binhai New Area of Tianjin by using a mobile vehicle lidar system. Ground-based lidar data, local meteorological information, and back trajectories from the HYSPLIT model were analyzed.
The mobile vehicle lidar technology can obtain the profile of the atmospheric particulate matter quickly, analyze the generating and vanishing process, and the transboundary transport by combining with the macro environment, such as meteorological and topographic conditions, "according to Prof. Tianshu Zhang.
Future research will focus on the detection of flux and the total amount of particulate matters presented by combining the technology with wind profiles.
车载激光雷达走航技术——更加快速精准探测城市大气污染
图片说明（一）：大气雾霾污染移动监测车
图片说明（二）：气溶胶消光系数空间分布
近年来中国不少地区深受雾霾困扰，居民出行多使用防霾口罩来减少雾霾吸入，因此科研人员希望能有效的对大气污染进行探测从而加以整治。目前国内外开展的激光雷达探测多以地基定点探测和适用于大范围区域机载和星载激光雷达探测为主。而对于城市尺度大气颗粒物污染的时空分布和输送规律，需要更快速的时间分辨能力和更精细的空间分辨能力。
基于这一要求，中国科学院安徽光学精密机械研究所的张天舒研究员课题组提出了利用车载激光雷达走航观测技术进行城市区域大气颗粒物的探测方法。相关研究成果发表在Chinese Optics Letters 2016 年第6 期上 (L.H. Lv et al., Application of mobile vehicle lidar for urban air pollution monitoringApplication of mobile vehicle lidar for urban air pollution monitoring)。
车载激光雷达技术是基于米氏散射原理，利用激光对大气颗粒物的时空分布进行遥感探测，获取大气消光系数、退偏振比、边界层高度、光学厚度等参数，分析区域污染物分布、输送特征与来源。
该课题组利用车载激光雷达对天津市滨海新区上空的颗粒物进行了走航观测，结合定点激光雷达数据、地面气象数据、后向轨迹分析等对该区域的大气颗粒物污染进行了深入的讨论和分析。
张天舒研究员认为，该研究提出的车载激光雷达走航探测技术，能够快速获得区域内大气颗粒物剖面，结合气象、地形等宏观环境条件，能够有效分析颗粒物污染的生消过程和跨界输送，在区域颗粒物污染探测方面有重要的应用价值。
后续工作主要是结合风廓线数据评估颗粒物区域输送通量与总量。