基于多角度偏振成像仪数据的动态分辨率水云滴谱反演  

Dynamic Resolution Retrieval of Water Particle Size Distribution Based on Directional Polarization Camera Data

作　　者：余海啸 孙晓兵 提汝芳[1,3] 涂碧海 刘晓[1,3] 黄红莲 王则灵 韦祎晨 王宇轩 Yu Haixiao;Sun Xiaobing;Ti Rufang;Tu Bihai;Liu Xiao;Huang Honglian;Wang Zeling;Wei Yichen;Wang Yuxuan(Hefei Institutes of Physical Science,Anhui Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Hefei 230031,Anhui,China;University of Science and Technology of China,Hefei 230031,Anhui,China;Key Laboratory of Optical Calibration and Characterization,Chinese Academy of Sciences,Hefei 230031,Anhui,China)

机构地区：[1]中国科学院合肥物质科学研究院安徽光学精密机械研究所,安徽合肥230031 [2]中国科学技术大学,安徽合肥230031 [3]中国科学院通用光学定标与表征技术重点实验室,安徽合肥230031

出　　处：《光学学报》2024年第24期31-40,共10页Acta Optica Sinica

基　　金：航天科技创新应用研究项目(E23Y0H555S1,62502510201);中国科学院重点实验室基金(E33Y0HB42P1);中国高分辨率对地观测专项(30-Y20A010-9007-17/18);中国资源卫星数据与应用中心项目(HFWZ2020080302)。

摘　　要：基于水云偏振辐射特性和辐射传输理论,提出多角度偏振数据的动态分辨率云滴谱反演方法,根据卫星成像几何和云特性对视场内不同尺度的反演可行性进行定量评估。所提方法通过逐像元选定最优像元合并策略,在保证反演精度的同时提高反演的分辨率,该反演方法可应用于多角度偏振成像仪(DPC)观测数据。结果显示,相较于POLDER(polarization and directionality of the Earth’s reflectance)云滴谱产品采用的25 pixel×25 pixel的固定反演尺度,所提方法的反演尺度在1 pixel×1 pixel至7 pixel×7 pixel之间动态调整,实现了反演分辨率的提升。与MODIS(moderate resolution imaging spectroradiometer)的云有效粒子半径产品对比发现,云有效粒子半径的反演结果误差小于2.05μm的占比超过50%,整体分布具有较好的一致性。这说明所提方法可以在提供更精细反演结果的同时,保持较高的反演精度。该研究为进一步提高国产多角度偏振数据的利用效率和云滴谱反演精度提供了思路。Objective Clouds play a crucial role as intermediary factors in maintaining the balance of atmospheric radiation energy and water cycle.The particle size distribution(PSD)and the optical and microphysical properties of clouds are intricately linked.Therefore,precise determination of PSD is pivotal for analyzing the interactions among different atmospheric components.Polarized remote sensing,a novel atmospheric detection technology,can be utilized to retrieve the PSD of water clouds.Multidirectional observation information can be leveraged to retrieve PSD.However,current methods overlook sensor scattering angle coverage and actual cloud characteristics.The fixedresolution sampling method within the field of view(FOV)neglects the influence of sensor imaging characteristics and cloud heterogeneity.Therefore,conducting studies aimed at enhancing the accuracy of water PSD inversion based on sensor imaging and cloud characteristics is important for atmospheric research.Methods In PSD retrieval research using polarized multiangle observation data,the selection of inversion scale significantly influences the number of available observation angles and the cloud’s heterogeneity.To address these limitations,we propose a dynamic scale PSD retrieval method based on multiangle polarized data,leveraging the polarized radiation characteristics of water clouds and radiation transmission theory.We conduct a quantitative evaluation of retrieval feasibility at various scales within satellite imaging geometry and cloud characteristics.Our method utilizes an optimal pixel merging strategy at a pixelbypixel level to improve inversion resolution while maintaining accuracy,ultimately applying the inversion method to directional polarization camera(DPC)observation data.Results indicate that,unlike the fixed retrieval scale of 25 pixel×25 pixel used in POLDER(polarization and directionality of the Earth’s reflectance)product,our method dynamically adjusts the inversion scale between 1 pixel×1 pixel and 7 pixel×7 pixel,leading to imp

关 键 词：水云 云滴谱分布 多角度偏振成像仪 云异质性 空间尺度 

分 类 号：P407[天文地球—大气科学及气象学]