title: Assimilation of remote sensing observations into a sediment transport model of China's largest freshwater lake: spatial and temporal effects.
abstract: Numerical models are important tools that are used in studies of sediment dynamics in inland and coastal waters, and these models can now benefit from the use of integrated remote sensing observations. This study explores a scheme for assimilating remotely sensed suspended sediment (from charge-coupled device (CCD) images obtained from the Huanjing (HJ) satellite) into a two-dimensional sediment transport model of Poyang Lake, the largest freshwater lake in China. Optimal interpolation is used as the assimilation method, and model predictions are obtained by combining four remote sensing images. The parameters for optimal interpolation are determined through a series of assimilation experiments evaluating the sediment predictions based on field measurements. The model with assimilation of remotely sensed sediment reduces the root-mean-square error of the predicted sediment concentrations by 39.4% relative to the model without assimilation, demonstrating the effectiveness of the assimilation scheme. The spatial effect of assimilation is explored by comparing model predictions with remotely sensed sediment, revealing that the model with assimilation generates reasonable spatial distribution patterns of suspended sediment. The temporal effect of assimilation on the model's predictive capabilities varies spatially, with an average temporal effect of approximately 10.8 days. The current velocities which dominate the rate and direction of sediment transport most likely result in spatial differences in the temporal effect of assimilation on model predictions.
authors.affiliation: Key Laboratory of Ecological Impacts of Hydraulic-Projects and Restoration of Aquatic Ecosystem of Ministry of Water Resources, The Institute of Hydroecology, Ministry of Water Resource and Chinese Academy of Sciences, Wuhan, 430079, China.|State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan, 430079, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan, 430079, China. xiaoling_chen@whu.edu.cn.|Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, Nanchang, 330022, China. xiaoling_chen@whu.edu.cn.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan, 430079, China.
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Lu
authors.affiliation: Sichuan Engineering Research Center for Emergency Mapping & Disaster Reduction, Chengdu, 610041, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
mesh_terms: D002681:China; D004784:Environmental Monitoring / Q000379:methods*; D060106:Lakes; D008962:Models, Theoretical; D058998:Remote Sensing Technology
keywords: Assimilation; Optimal interpolation; Poyang lake; Remote sensing sediment; Sediment transport model; Spatial and temporal effect