海面溢油溢出量的高光谱估计方法研究

The volume of oil spill should be determined after the occurrence of oil pill for disaster evaluation, cleaning, and claim for compensation. However, the accuracy of estimation of oil spill volume is inaccurate due to the marine environment, atmospheric effects, and detection methods. The recent research still has a lot of deviation, nearly an order of magnitude difference between the estimated maximum and minimum estimated. In regard to this, this project presents a new method to account for the impact of the marine environment, atmospheric effects, and detection methods. Based on the physical characteristics of the different thickness of the oil-water emulsion, the distribution of the oil droplets is simulated according to the marine environment. By introducing the Monte Carlo method, the spectral characteristics of the oil-water emulsion is calculated. Next, an atmosphere correction model is build by considering the atmospheric absorption, scattering and radiation are considered to simulate the atmosphere impact for oil spill spectra. Finally, the spectral characteristics of the oil-water emulsion is extracted, particularly, the absorption band position, absorption width, absorption depth. And a new detection method is designed to detect the thickness of spill oil based on Neyman-Person Criterion. Further, by combining with the oil spill area, the volume of oil is obtained.

海洋溢油发生后其危害评估，清理以及理赔等方面都需了解确切的溢出量。由于受到海洋环境，大气效应，检测方法等方面的影响，现阶段溢油量估计仍然具有较大的偏差，最大估计与最小估计之间相差近一个数量级。 鉴于此，本项目针对海洋环境，大气影响以及检测方法中存在的问题，提出以不同厚度油水乳状液的物理特性为基础，依据海洋环境，油水混合比例，得到油滴分布情况，然后利用Monte Carlo 方法计算得到油水乳状液的光谱特性。继而考虑大气吸收、散射和大气自身的辐射，建立大气辐射传输修正模型，获得经大气修正后的溢油光谱。最后，提取油水乳状液光谱的吸收带位置，吸收带宽度，吸收带深度等特征，并对这些特征进行增强，然后以N-P准则为基础，设计溢油检测方法，检测溢油的厚度。结合溢油面积，最终得到海面溢油溢出量。

海面溢油给海洋生态环境，渔业、旅游业带来极大的危害。针对海面溢油溢出量的估计问题，本项目采用基于高光谱遥感图像的方法开展研究，研究工作如下：1）以海面溢油物理特性为基础，采用仿真计算的方法获取了不同厚度，不同有油水比的溢油本征高光谱。2）依据溢油成像遥感器和海面之间的几何关系，建立了大气辐射传输模型去除大气效应对溢油光谱的影响。3）提出了一种基于自适应匹配滤波的高光谱遥感图像溢油自动检测方法，根据溢油光谱的C-H键特征，提取参考光谱，进而依据海水的红外波段特征提取海洋背景参数，实现了海面溢油的自动检测。4）提出了一种自适应海面溢油参考光谱获取方法，对基于密度聚类的方法进行改进，采用溢油光谱的特征，构造决策图，可自适应地得到溢油的参考光谱。5）针对海面溢油场景中的云干扰问题，综合考虑溢油、海水和云背景的光谱特征，提出了一种云背景抑制方法，能够去除溢油检测和估计过程中云背景的影响。6）利用不同厚度溢油参考光谱，在场景中匹配，初步实现了高光谱遥感图像的海面溢油溢出量估计。