基于海洋多角度太阳耀光遥感的海面粗糙度反演研究

The sea surface roughness (SSR) is used to characterize the small scale fluctuation of the sea surface, and it is a key physical parameters of ocean dynamics and oil spill remote sensing. At present, there are no effective measurement and observation methods, which seriously affect the development of quantitative remote sensing. Considering that the sun glitter intensity is sensitive to the sea surface rough condition, this project will carry out the study on inversion of SSR under the influence of wind speed and direction and the refractive index using multi-angle sun glitter remote sensing obtained synchronous or quasi synchronous at different observation angles. First of all, we focus on the radiation characteristics and physical mechanisms of multi angle remote sensing of sun glitter through simulation and analyzing of multi angle sun glitter remote sensing. Secondly, we study the relationships between the many times of sun glitter information from multiple synchronous or quasi synchronization observations and Finel reflectivity and slope probability distribution of sea surface wave, and overcome the difficulties in quantitative inversion of SSR considering the influence of wind speed and wind direction, and oil film refractive index. Then, we will discuss the optimization imaging geometry and its applicability for the SSR with multi-angle sun glitter remote sensing. Finally, the aerial remote sensing synchronous experiment of unmanned aerial vehicles (UAV) will be carried out to test and evaluate the results. This project will expect to extend the sun glitter remote sensing from single / bio angle to multi-angle remote sensing with more observation angles, to enhance the ability of quantitative inversion of SSR and oil film refractive index. This work will not only promote the development of quantitative remote sensing of marine oil spill and dynamic phenomenon, but also improve the development of sun glitter remote sensing in multi-angle directions. Therefore, this project has very important practical value and scientific significance.

海面粗糙度是表征海面微小尺度起伏程度的物理量，是海洋动力过程研究和海洋遥感研究中的关键参数，目前尚没有直接的测量和观测手段。基于太阳耀光对海面粗糙状况十分敏感的特性，本项目利用同步或准同步观测的多角度太阳耀光信息，开展考虑风速风向和折射率影响的海面粗糙度遥感反演研究。首先，通过多角度太阳耀光遥感资料分析和模拟仿真，进一步理解多角度太阳耀光辐射强度特征及其物理含义，开展同步或准同步的多角度太阳耀光信息与菲涅尔反射率和海面粗糙度间的定量关系研究，攻克考虑风速风向和油膜折射率影响的海面粗糙度定量反演难题，并探讨多角度太阳耀光遥感成像几何优化组合及适用性。然后，开展无人机编队航空遥感试验，进行结果检验和评估。本项目期望将太阳耀光遥感从单/双角度拓展到更多观测角度的多角度太阳耀光遥感，提升海面粗糙度遥感反演能力，促进海洋动力过程和溢油污染的定量遥感发展，具有十分重要的应用价值和科学意义。

本项目针对海面粗超度和折射率等海气界面关键参数定量探测需要，围绕多角度太阳耀光遥感机理和探测模型。项目主要开展了多角度太阳耀光遥感最优成像几何关系讨论、多角度太阳耀光遥感最优成像几何评估，在此基础上聚焦了高分辨率海面粗糙度和等效折射率太阳耀光遥感反演模型研究，并以溢油和浅海沙波地形为例开展探测应用。项目取得的主要研究进展有以下几个方面：1）依据传感器固有误差和辐射校正误差的特性，设计了基于误差传递的最优成像几何验证仿真模型，讨论了航空和卫星平台的最优成像几何组合，并通过无人机编队多角度航空遥感试验进行了验证。2）突破了基于多角度太阳耀光遥感的高分辨率的溢油海面粗糙度和折射率遥感一体化反演难题。3）基于多角度太阳耀光遥感图像反演的高精度海面粗糙度为基础，拓展了高精度海面粗糙度在大型浅海沙波地形的应用效率。本项目进一步拓展了多角度太阳耀光遥感的机理模型从，提升了海面粗糙度和等效折射率等海气界面关键参数的遥感反演能力，具有十分重要的应用价值和科学意义。