基于黄河口海域实测数据,建立了利用745nm(模型1)和680nm(模型2)波段遥感反射率的颗粒有机碳(POC)浓度反演模型,得到的平均相对误差(APD)均低于26%,其中模型1表现更优。结合海洋水色成像仪(GOCI)影像和实测数据对两个模型进行了精度评估,平均相对误差均在30%以内。基于所建立的模型和卫星遥感影像,分析了逐时、大风过程(几日之间)、季节变化三种情况下黄河口海域POC浓度的时空变化特征。结果表明,冬季POC浓度整体较高,夏季POC浓度整体较低;渤海湾附近出现POC浓度最高值。三种情况下,POC浓度的变化范围在同一尺度上,表明短时间间隔并不意味着POC浓度变化范围也小,其季节平均效应是显著的。
Two particulate organic carbon(POC)concentration retrieval models are developed with remote sensing reflectance at 745nm(model 1)and 680nm(model 2)based on the data collected near the Yellow River Estuary.The average percentage differences(APD)of the two models are less than 26%,and model 1 performs better.Accuracy evaluation is carried out with geostationary ocean color imager(GOCI)images and the measured data,and the average relative error is less than 30%.The developed models are used to analyze the temporal and spatial variation of POC concentration in the seawater near the Yellow River Estuary on the time scales of hour,day(for strong wind process)and season,respectively.The results show that the POC concentration is high in winter,and the POC concentration is low in summer.The peak value of POC concentration is found near the Bohai Bay.The variations of POC concentration are of the same order of magnitude under the three conditions,which shows that the obvious change of POC concentration may happen even in shorter time scale,while the seasonal mean effect is significant.