Remote Sensing Reflectance Spectrum Analysis Of Oil Polluted Water Based On Hydrolight

The problem of oil pollution is particularly serious in water pollution.The existence of oil will change the apparent and inherent optical properties of water,and then affect the water ecosystem.The monitoring of oil polluted water is very important for the early warning,prediction and radiation transfer of oil spill.Remote sensing technology is one of the important means to detect marine oil pollution,and its core physical quantity,remote sensing reflectance(R_rs),is the comprehensive embodiment of the optical characteristics of water components,which connects the absorption characteristics and scattering characteristics of water components,and reflects the biochemical characteristics of water.Carrying out R_rs spectroscopic studies on petroleum-polluted water bodies to clarify the effects of oil substances on R_rs which will helpful to improve the process of basic research and Application Research of ocean color remote sensing,and lay a foundation for remote sensing detection mechanism of oil polluted water,identification of oil pollution model and improvement of accuracy of oil concentration inversion model.This article takes R_rs of oily water as the research object to explore the influence of oil concentration on R_rs of different water components.In this paper,taking the R_rs of oil polluted water as the research object,the radiation transfer model Hydrolight is used to simulate the R_rs spectra of single component and different components of oil polluted water,and to explore the influence of oil concentration on the R_rs of different water components.Three stations along the coast of Dalian Port were selected as the research area,and the following work was done:1)Based on the data of inherent optical quantity of oil-polluted water bodies measured in the sea area of Dalian Port,calculated and analyzed the vertical distribution of oil concentration and its changes over time;2)Explore the feasibility of using the radiation transfer model Hydrolight to study the radiation transfer characteristics of oil-bearing water;3)Using the Hydrolight model and the proportioning method,the R_rs spectra of a single component of oil,sand,algae and a mixed water body of different components were simulated,and the contribution of oil substances to R_rs was explored;4)The effectiveness of Hydrolight’s simulation of oil-bearing water R_rs and its influence on ocean color remote sensing algorithms are explored.The results show that:（1）The radiative transfer model Hydrolight is an effective tool for the study of the radiative transfer characteristics of oil polluted water,which plays an important role in the construction of inversion model of oil concentration and improving the inversion accuracy of the relevant bio-optical model;（2）Due to the influence of tide,the concentration of oil at each station has no obvious rule with time;（3）In the water body containing only oil,the R_rsdecreases with the increase of wavelength,and its value decreases with the increase of oil concentration(C_oil)in the wavelength range of 400-480 nm,but increases with the increase of C_oil in the range of480-700 nm;（4）In the oil-sand mixed water,when the concentration of suspended sediment(C_spm)is high,the R_rs value will decrease with the increase of C_oil,but the spectral shape will not change;with the increase of C_spm,the value of R_rs will increase,and the shape of the spectrum will change significantly;（5）In the oil-algae mixed water,the R_rs will increase with the increase of C_oil and the spectral shape will not change;As the chlorophyll concentration C_chl increases,the spectrum gradually reflects the spectral characteristics of chlorophyll,but the increase in the peak area is affected by C_oil;（6）For the oil,sand and algae mixed water body,the R_rs spectrum shape is mainly affected by suspended sediment,and secondly by chlorophyll,and the oil substance has little effect on it;The presence of chlorophyll limits the"red shift"phenomenon of suspended sediment;The C_oil has little effect on the shape of R_rs spectrum,but the change of the value is related to the C_chl and C_spm.