基于Sentinel-3 OLCI数据的渤海水色状况时空变化特征  

Spatiotemporal variation of water color conditions in the Bohai Sea based on Sentinel-3OLCI data

作　　者：王林[1] 王祥[1] 陈艳拢[1] 高思雯 曾怡乐 孟庆辉[1] 王新新[1] WANG Lin;WANG Xiang;CHEN Yan-long;GAO Si-wen;ZENG Yi-le;MENG Qing-hui;WANG Xin-xin(National Marine Environmental Monitoring Center,Dalian 116023,China)

机构地区：[1]国家海洋环境监测中心,辽宁大连116023

出　　处：《中国环境科学》2023年第9期4828-4836,共9页China Environmental Science

基　　金：国家重点研发计划项目(2019YFC1407904,2018YFC1407605)。

摘　　要：采用福莱尔水色计可将自然水体颜色从深蓝到红棕分为21个级别,用来记录全球海洋和内陆水体的颜色.目前,与福莱尔水色计21个级别颜色相对应的FUI(Forel-Ule index)水色指数已有成熟的卫星遥感提取方法.以渤海为研究区,利用Sentinel-3 OLCI卫星数据提取了2018~2022年近5a渤海月度、年度FUI水色指数,研究了水色状况的时空变化特征.结果表明,渤海FUI时空变化特征显著,辽东湾、渤海湾及莱州湾沿岸海域FUI较高,水体浑浊,水色状况较差;而秦皇岛海域及其它离岸海域FUI较低,水体相对清澈,水色状况较好.1~12月,渤海FUI月平均值呈“V”型变化特征,即FUI由大变小再变大,体现出渤海水色状况由浊变清再变浊的过程.2018~2022年,FUI年平均值整体呈现下降趋势,水色状况转好;2018~2019年FUI年平均值的降幅最高,渤海综合治理攻坚战初见成效,2020年降至攻坚战实施期间最低水平,2021年出现小幅回升,2022年FUI年平均值则降至历年最低;与2020年相比,2022年渤海水色状况转好、稳定、变差的海域面积占比分别为36.05%、50.45%、13.50%,达到近5a最佳状态,可见渤海综合治理攻坚战对其生态环境的改善发挥了重要作用.因此,利用遥感技术监测FUI水色指数可有效提升我国海洋生态环境常态化巡查监管能力,具有非常重要的实际应用价值.The Forel-Ule scale was introduced to record the colors of oceans and inland waters.It classified natural water colors into 21 grades ranging from dark blue to reddish brown.With satellite data,it has been possible to extract the Forel-Ule index(FUI),which correspond to 21 levels of the Forel-Ule scale.Based on Sentinel-3OLCI satellite data,the monthly and annual FUI of the Bohai Sea for the past five years from 2018 to 2022 was extracted.In addition,spatial and temporal variations in water color conditions were investigated.As can be seen from the results,both the spatial and temporal variation of FUI in the Bohai Sea was significant.High FUI values were observed in the coastal waters of Liaodong Bay,Bohai Bay,and Laizhou Bay.This indicated turbid water and poor water color.In contrast,low FUI values were observed in Qinhuangdao and other offshore waters,reflecting relatively clear water and good water color.A"V"shaped change,i.e.,the FUI varied from large to small and then to large,from January to December,in the variation of the monthly FUI average in the Bohai Sea was captured,illustrating the process of the Bohai Sea's water color condition from turbid to clear and then to turbid.An overall decreasing trend in the annual FUI average value was detected,corresponding to the water color condition getting better,from 2018 to 2022.During this period,the highest decreasing rate happened from 2018 to 2019,subject to the Bohai Sea comprehensive management battle.The lowest level was in 2020,followed by a slight rebound in 2021.The annual FUI average value reached its lowest level in 2022.Compared with 2020,the percentage of sea area with improved,stable,and deteriorating water color in 2022 was 36.05%,50.45%,and 13.50%respectively.This was the best performance in five years.Therefore,it was seen that comprehensive management of the Bohai Sea had played an active role in improving its ecological environment.Monitoring FUI with remote sensing increased the capacity for regular inspections and supervision of China's ma

关 键 词：FUI水色指数 时空变化 Sentinel-3 OLCI数据 遥感反演 渤海 

分 类 号：X55[环境科学与工程—环境工程]