珠江口近岸水域实测光谱与Sentinel-2卫星影像光谱的对比分析  

Comparison of in-situ measured spectrum and satellite image spectrum of the Pearl River Estuary

作　　者：李海桃 解学通[2] 杨现坤 夏雪宁 张秦 LI Hai-tao;XIE Xue-tong;YANG Xian-kun;XIA Xue-ning;ZHANG Qin(Guangzhou Maritime Hydrographic Center,Southern Navigation Service Center,Ministry of Transport,Guangzhou 510320,China;School of Geography and Remote Sensing,Guangzhou University,Guangzhou 510006,China)

机构地区：[1]交通运输部南海航海保障中心广州海事测绘中心,广东广州510320 [2]广州大学地理科学与遥感学院,广东广州510006

出　　处：《广州大学学报（自然科学版）》2023年第6期40-48,共9页Journal of Guangzhou University:Natural Science Edition

基　　金：国家自然科学基金面上资助项目(41876204);广东省海洋专项资助项目(粤自然资合[2020]013)。

摘　　要：地面实测的水体高光谱数据与卫星影像上的多光谱数据都是水质反演与监测中的重要数据来源,二者之间存在光谱分辨率等差异,其关联性在一定程度上影响了水质反演的精度。为探究实测光谱与影像光谱之间的相关关系,文章以珠江口近岸水域为研究区,基于2020年与2021年间共计4轮同步实测的水体高光谱与哨兵2号影像数据,分别从光谱形态、反射率的角度对比分析不同大气校正算法的影像结果与实测数据之间的关系与差异。分别将等效反射率与Sen2cor(Sentinel-2 atmospheric correction)、C2RCC(Case-2 Regional/Coast Color)大气校正算法影像结果进行两两对比,得出以下结论:①Sen2cor大气校正算法在浑浊水体中表现更好,其影像光谱形态与实测光谱契合程度更高;②C2RCC大气校正算法在一般水体或非浑浊水体中的效果更好,其影像上的绝对反射率可以更好地还原水体的地面反射率。Hyperspectral data of in-situ measurement of water surface and spectral data of satellite im-ages are both important data sources in water quality monitoring.There are differences between them in spectral resolution,and their correlation affects the accuracy of water quality retrieval to a certain extent.In order to explore the correlation between the two data sources,this paper takes the coastal waters of the Pearl River Estuary as the research area,and is based on the hyperspectral data of water from four rounds of synchronous measurements in 2020 and 2021 and Sentinel-2 images.In addition,the relationships and differences between the image results of different atmospheric correction algo-rithms and the data of in-situ measurements were compared from the perspectives of spectral morpholo-gy and reflectance.By comparing equivalent reflectance with Sen2cor and C2RCC(Case-2 Regional/Coast color)atmospheric correction algorithms,the following conclusions are drawn:Sen2cor algo-rithm performs better in turbid water,and the spectral morphology of the image accords with the in-si-tu spectrum better.The performance of C2RCC algorithm is better in general water or non-turbidite water,and the absolute reflectance on the image is closer to the reflectance of in-situ measurement.

关 键 词：高光谱 等效反射率 哨兵2号 Sen2cor C2RCC 

分 类 号：P237[天文地球—摄影测量与遥感]