Download or read book Remote Sensing and Three dimensional Numerical Model Analysis of Suspended Sediment Distributions in Sandusky Bay Lake Erie Nearshore Region written by Chieh-Cheng James Yen and published by . This book was released on 1987 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book NOAA Estuary of the month Seminar Series written by and published by . This book was released on 1989 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Remote Sensing of Suspended Sediment in San Francisco Bay Using Satellite and Drone Imagery written by Joseph Henry Adelson and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Suspended sediment in San Francisco Bay affects the economic and ecological health of the estuary and its surrounding region by limiting light availability for photosynthesis, transporting contaminants, nourishing marsh restoration projects, infilling shipping channels, and providing protection to the shoreline from sea level rise via accretion on mudflats. Traditional efforts to study sediment transport phenomena have relied upon in situ measurements and numerical modeling, but these approaches have limitations. In situ measurement techniques rely on point measurements with high temporal resolution, yet they are difficult to deploy over large spatial areas. Models provide useful insight into the spatial heterogeneity of sediment processes. However, they rely on initial and boundary conditions and parameterizations that are based on observations, therefore the accuracy of models is also constrained in part by the limitations of in situ measurements. This dissertation presents remote sensing measurements from satellites and unmanned aerial vehicles (UAVs) to understand suspended sediment transport processes in estuaries like San Francisco Bay. Twelve methods for inferring suspended sediment concentration (SSC) from Landsat 7 imagery were compared using k-folds validation and assessed based on their abilities to recreate in situ SSC measurements from one meter below the surface. The best performer was the model of Nechad et al. (2010) using the red wavelength band with coefficients determined via Huber regression, with mean absolute error of 5.94 mg L-1 and bias of 0.15 mg L-1. Satellite-derived SSC observations compare well with USGS transects indicating that the method is well-suited to supplement cruise data that is costly to acquire and therefore limited in its frequency. Remote sensing measurements were aggregated by location, season, or tidal phase to understand the variability of SSC and to compare probability densities with in situ measurements. These results show that surface SSC is heightened in the shoals during summer months and has trended downward in Suisun and Grizzly Bays since 1999. Using satellite imagery from 2014-2017, remotely sensed surface SSC derived from the Nechad method was paired with bottom stress estimates based on two-dimensional hydrodynamic and fetch-limited wave models to investigate the relationship between surface SSC and flow. Observations of SSC closely fit a lognormal distribution though the shape, characterized by the modal value, depend on binning criteria including embayment, depth, and wave height. When binned by model-derived bottom shear stress, the modal value of the SSC distribution exhibited an inflection point at the critical shear stress for erosion. This suggests that remote sensing can be used to derive critical stresses that are otherwise difficult to measure. To account for the limitations of satellite imagery such as low spatial resolution and low temporal resolution (Landsat 7 overpasses occurred roughly once every 16 days), a method was developed to infer surface SSC from UAV-based imagery. While traditional remote sensing platforms take imagery at approximately a nadir viewing angle and provide multispectral images that are aligned with one another, an off-the-shelf camera aboard a UAV may not adhere to those qualities. Low cost multi-spectral cameras often include individual sensors for each band. The slight misalignment between images violates assumptions in two-band glint correction algorithms. Additionally, UAVs must tilt to fly and compensate for wind requiring images to occasionally be taken at angles more oblique than most satellite imagery. The method developed in this dissertation adapts previous techniques for sun glint correction for misaligned multispectral images and offers a novel approach to reduce the effects of camera orientation for oblique angles. During a field campaign, the UAV-based method to capture remote sensing reflectance was validated via comparison with in situ measurements made with a hyperspectral radiometer, and its ability to accurately infer SSC was verified based on in situ water samples. It was found that a polarizing filter is necessary to mitigate much of the glare on the water surface. A series of test flights were conducted to measure the surface SSC along a transect parallel to the Dumbarton Bridge during different phases of the tidal cycle. To reduce the impact of variability of incoming light, the flights were conducted over a period of 12 days at the same solar zenith angle during each day. Because the tide arrives later by roughly 50 minutes each day, consecutive daily transects over 12 days provided the variability over a tidal cycle. Cross-sectional sediment flux was computed from the remotely sensed surface SSC measurements and compared well to flux values estimated from in situ USGS observations.

Download or read book Analysis of Suspended Sediment Distributions in the Surface Waters of Delaware Bay Using Remote Sensing of Optical Properties written by Richard Paul Stumpf and published by . This book was released on 1984 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Three dimensional Numerical Modelling of Sediment Transport Processes in Non stratified Estuarine and Coastal Waters written by M. Cahyono and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Basin scale Waves Dynamics and Sediment Resuspension Mechanics in Central Lake Erie written by Reza Valipour and published by . This book was released on 2012 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: High-resolution physical and biogeochemical field data in central Lake Erie during the summers of 2008-2009 along with a three-dimensional numerical model were used to investigate the dynamics of basin scale waves and sediment resuspension mechanisms. In Chapter 2, the modal response of the Poincaré waves in the lake is assessed. The vertical mode-one Poincaré wave was found to be mostly dominant during the seasonal stratified period. The horizontal modal structure was also investigated in a sensitivity analysis, using the numerical model forced with real and idealized wind events. In Chapter 3, dynamics of bottom mixed layer (BML), primarily forced in the outer layer by surface seiches and Poincaré waves is studied for two 10-days representative intervals of weak and strong stratification. Shear velocity was calculated by least square fitting the well-known law-of-the-wall equation to observed near-bed velocity in a region of constant shear stress. Height of the BML is computed using water density (from water temperature) and compared with heights of logarithmic layer approximated using the law-of-the-wall equation and its modified form with buoyancy length scale term. Published equations for estimating BML heights are evaluated and modified for the lake. In Chapter 4, we investigate physical processes leading to sediment resuspension in the lake including surface waves (periods of 4-8s), up/downwelling events (periods of 3-4 day), and high frequency internal waves (periods of 5-45min). Temporal changes in near-bottom sediment resuspension are illustrated using changes in acoustic backscatter signals from current profilers and time series of turbidity measurements to identify the mechanism responsible for sediment resuspension. Resuspension is parameterized as a function of the critical velocity ~0.25ms-1 and from surface waves using linear wave theory. Finally, based on the critical velocity and sediment grain size analysis (from in-site field data), critical shear stress and Shields parameter are calculated and compared with previous observations in Lake Erie and in other locations suggesting a modified Shields diagram for silty bed materials.

Download or read book Modelling and Analysis of Fine Sediment Transport in Wave Current Bottom Boundary Layer written by Liqin Zuo and published by CRC Press. This book was released on 2018-06-19 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: The evolution and utilization of estuarine and coastal regions are greatly restricted by sediment problems. This thesis aims to better understand fine sediment transport under combined action of waves and currents, especially in the wave-current bottom boundary layer (BBL). Field observations, experimental data analysis, theoretical analysis and numerical models are employed. Silt-dominated sediments are sensitive to flow dynamics and the suspended sediment concentration (SSC) increase rapidly under strong flow dynamics. This research unveils several fundamental aspects of silty sediment, i.e., the criterion of the incipient motion, the SSC profiles and their phase-averaged parameterization in wave-dominated conditions. An expression for sediment incipient motion is proposed for silt-sand sediment under combined wave and current conditions. A process based intra-wave 1DV model for flow-sediment dynamics near the bed is developed in combined wave-current conditions. The high concentration layer (HCL) was simulated and sensitivity analysis was carried out by the 1DV model on factors that impact the SSC in the HCL. Finally, based on the 1DV model, the formulations of the mean SSC profile of silt-sand sediments in wave conditions were proposed. The developed approaches are expected to be applied in engineering practice and further simulation.

Download or read book Deposition and Simulation of Sediment Transport in the Lower Susquehanna River Reservoir System written by and published by . This book was released on 1995 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Three dimensional Numerical Modelling of Sediment Transport Processes in Non stratified Estuarine and Coastal Waters written by Cahyono and published by . This book was released on 1992 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Details are given herein of the development, refinement and application of a higher-order accurate 3-D finite difference model for non-cohesive suspended sediment transport processes, in non-stratified estuarine and coastal waters. The velocity fields are computed using a 2-D horizontal depth-integrated model, in combination with either an assumed Iogarithmic velocity profile or a velocity profile obtained from field data. Also, for convenience in handling variable bed topographies and for better vertical resolution, a sigma-stretching co-ordinate system has been used. In order to gain insight into the relative merits of various numerical schemes for modelling the convection of high concentration gradients, in terms of both accuracy and efficiency, thirty six existing finite difference schemes and two splitting techniques have been reviewed and compared by applying them to the following cases:....

Download or read book A Numerical Model of Cohesive Suspended Sediment Dynamics written by N. Hawley and published by . This book was released on 1983 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of the Dispersal of Suspended Sediment from the Fraser and Skagit River Into Northern Puget Sound Using LANDSAT Imagery written by Richard A. Feely and published by . This book was released on 1979 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book SED3D a Three dimensional Numerical Model of Hydrodynamics and Sediment Transport in Lakes and Estuaries written by Y. Peter Sheng and published by . This book was released on 1991* with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Status and Trends in Suspended sediment Discharges Soil Erosion and Conservation Tillage in the Maumee River Basin Ohio Michigan and Indiana written by Donna N. Myers and published by . This book was released on 2000 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Remotely Sensed Distributions of Suspended Sediment in Lake Pontchartrain written by Jeanne Capdevielle Hart and published by . This book was released on 1978 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Models for Suspended Sediment Distribution written by Luis Eduardo Rubio Cardona and published by . This book was released on 1974 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of Methods Used in Measurement and Analysis of Sediment Loads in Streams written by and published by . This book was released on 1941 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Sensitivity and Uncertainty Analysis of the Numerical Simulation of Three dimensional Sediment Transport in Lake Okeechobee written by Y. Peter Sheng and published by . This book was released on 1991 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: