HY-1C卫星COCTS L2A级产品在中国和欧洲近海的真实性检验  

Validation of L2A operational products of COCTS onboard HY-1C satellite across coastal waters in China and Europe

作　　者：韩冰[1] 贾迪 高飞[1] 郭凯[1] 朱建华[1] 李铜基[1] 马超飞[2] 刘建强[2] Giuseppe Zibordi HAN Bing;JIA Di;GAO Fei;GUO Kai;ZHU Jianhua;LI Tongji;MA Chaofei;LIU Jiangqiang;GIUSEPPE Zibordi(National Ocean Technology Center,Ministry of Natural Resources,Tianjin 300112,China;National Satellite Ocean Application Service,Ministry of Natural Resources,Beijing 100086,China;Instituteof Environment and Sustainability,Joint Research Center,Ispra 21027,Italy)

机构地区：[1]国家海洋技术中心,天津300112 [2]国家卫星海洋应用中心,北京100086 [3]Institute of Environment and Sustainability,Joint Research Center,Ispra 21027,Italy

出　　处：《遥感学报》2023年第1期26-42,共17页NATIONAL REMOTE SENSING BULLETIN

基　　金：中欧科技合作“龙计划”五期(编号:59053);国家重点研发计划(编号:2016YFC1400906);“十二五”海洋观测卫星地面系统黄东海光学遥感海上检验场观测系统建设(编号:HYYW01-HT-FZH-010);HY-1D卫星在轨测试海上试验与评价(编号:HYYW01-HT-SHY-001/K420CY022);HY-1C卫星在轨测试海上现场同步观测试验(编号:K4180C008)。

摘　　要：随着HY-1C卫星于2018年9月成功发射,中国海洋水色遥感进入业务化全球观测时代。海洋环境观测、生态环境监测以及海洋防灾减灾等都对海洋水色遥感提出了较高的定量化要求。本文基于国际通用的时空匹配方法,利用2018年和2020年海洋卫星在轨测试海上试验以及在中国东海、欧洲亚得里亚海近岸海域部署的自动太阳光度计(SeaPRISM)观测数据,对HY-1C卫星搭载的水色水温扫描仪(COCTS)的L2A级业务化产品(包括遥感反射率和气溶胶光学厚度)进行了真实性检验。研究发现,SeaPRISM自动测量能够提升数据获取效率和观测数据时间跨度,有助于更好刻画水色遥感产品误差的时间分布规律。检验结果表明,COCTS的遥感反射率与现场实测数据具有较好的一致性,但匹配数据的离散度较高,其蓝光波段、绿光波段和红光波段的遥感反射率在不同海域与实测数据的平均相对百分比偏差(RPD)和平均绝对百分比偏差(APD)分别为-5.6%和46.8%、11.8%和53.0%、101.4%和173.9%,而其气溶胶光学厚度的在不同海域与实测数据的RPD和APD分别为-14.2%和79.5%;COCTS遥感反射率光谱形状与实测数据一致性较高,但在不同海域表现出较大差异:中南海海域的谱形一致性非常高,但呈显著高估特点;中国东海海域的谱形相似度高,但存显著的低估;而欧洲亚得里亚海海域的谱形差异较大,即在蓝光波段呈现高估特点,而在绿光和红光波段呈现低估特点。对比同期的HY-1C卫星COCTS L2A及产品与AQUA卫星MODIS二级产品的检验结果发现,后者在遥感反射率估算精度和光谱谱形相似度方面表现更好,而在气溶胶光学厚度定量反演方面则没有表现出显著优势。本文的研究认为COCTS数据虽然已经在多个应用领域发挥了重要作用,但其业务化产品的定量化精度和水平仍有较大提升空间,至少L2A级产品是如此。Since the successful launch of HY-1C in September, 2018, China has entered a new era of operational global ocean color remote sensing. As one of its three major payloads, the Chinese Ocean Color and Temperature Scanner(COCTS) measures the radiances scattered from the atmosphere, ocean and sea surface in eight visible and near-infrared bands and two thermal infrared bands across a swath of over 2500 km. As many businesses such as marine environment observation, marine ecological monitoring and marine disaster prevention and mitigation are putting higher demands on quantitative ocean color products, we here validate operational L2A products retrieved from COCTS data across coastal waters across China and Europe, and also compare them with widely accepted L2 products of MODIS onboard AQUA satellite. Validation practice uses in-situ data obtained in field campaigns in the East and South China Sea in 2018 and 2020, and those derived by automated sun-photometers(SeaPRISM, CIMEL Inc.) deployed in the East China Sea and in the Adriatic Sea in Europe.Confined by that SeaPRISM can only produces remote-sensing reflectance and aerosol optical thickness directly, we only validate operational L2A products provided by COCTS, which include Remote Sensing Reflectance and Aerosol Optical Thickness. Match-up practice follows those protocols widely accepted in the ocean color community. It is found that SeaPRISM can provide in-situ data in a more efficient way and the data covers a larger temporal range, which facilitates characterizing temporal and spatial uncertainty of ocean color products. Validation results show that both remote-sensing reflectance and aerosol optical products of COCTS L2A products agree well with in-situ measurements, but their comparison shows larger deviation. The average relative percentage difference(RPD) between COCTS L2A product and field measurement across various coastal waters are-5.6%, 11.8% and 101.4% in blue, green and red bands respectively, while the average Absolute Percentage Ddifference(APD) a

关 键 词：HY-1C卫星 COCTS L2A级产品 真实性检验 中国近海 欧洲近海 遥感反射率 气溶胶光学厚度 

分 类 号：P2[天文地球—测绘科学与技术]