WAMSI 2 - Dredging Node - 3.1.1 - Review of Plume Characteristics

Predicting the distribution and fate for suspended sediment plumes associated with dredge operations may be achieved by advanced hydrodynamic modelling (REFS). The accuracy of the model outputs, or the level of confidence we associate with the modelled forecasts, depend to some degree on the model inputs, including parameters such as particle size distributions, particle densities, and particle settling rates. There is potential to infer optical products from the modelled 3 dimensional plume distribution, including spectral light attenuation, and spectral light intensity at the substrate. One of the approaches to testing or monitoring the accuracy of plume distribution models is to compare the modelled distributions to observed plume distributions. Optical remote sensing methods can provide reliable “maps” of plume extent, and reasonable estimates of various in-water geophysical parameters. Examples of remote sensing products include suspended sediment concentration, particle backscattering, and spectral light attenuation coefficients.

This review encompasses two main components:

1) Satellite and in situ observations used to monitor sediment plumes and assess the suitability of the different sensor platforms to provide the spatial and temporal resolution needed for model validation and calibration in WAMSI Dredging Theme 3.4. Remote sensing platforms will include MODIS data and high resolution products such as WorldView and RapidEye;

2) Available water quality data (such as TSS levels, light levels, sediment deposition rate, particle size distribution etc.) collected in Western Australia and associated with different types of dredges working in different geotechnical settings and metocean conditions.

借助先进的水动力建模（REFS），可预测疏浚作业相关悬浮泥沙羽流的分布与运移归宿。模型输出的精度，或是我们对模拟预报结果的置信水平，在一定程度上取决于模型输入参数，其中包括粒径分布、颗粒密度及颗粒沉降速率等。通过模拟得到的三维羽流分布，还可反演得到相关光学产品，包括光谱光衰减系数以及基底处的光谱光强。验证或监测泥沙羽流分布模型精度的方法之一，是将模拟得到的羽流分布与实测羽流分布进行对比。光学遥感方法可提供可靠的羽流范围"分布图"，并能合理估算各类水下地球物理参数。遥感产品示例包括悬浮泥沙浓度、粒子后向散射系数以及光谱光衰减系数。

本综述包含两大核心内容：
1) 用于监测泥沙羽流，并评估不同传感器平台是否能够提供WAMSI疏浚主题3.4中模型验证与校准所需的空间与时间分辨率的卫星及原位观测数据。遥感平台将包括MODIS数据，以及WorldView、RapidEye等高分辨率遥感产品；
2) 在西澳大利亚地区收集的、与不同岩土工程环境及海洋气象条件下作业的各类疏浚设备相关的现有水质数据（例如总悬浮固体（Total Suspended Solids，TSS）浓度、光照水平、泥沙沉积速率、粒径分布等）。