Development of a three-dimensional, regional, coupled wave, current, and sediment-transport model

http://joezambon.com/prof/pubs/2010_warner.pdf

Development of a Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System

Coastal morphodynamic evolution techniques

Marine plastic debris floating on the ocean surface is a major environmental problem. However, its distribution in the ocean is poorly mapped, and most of the plastic waste estimated to have entered the ocean from land is unaccounted for. Better understanding of how plastic debris is transported from coastal and marine sources is crucial to quantify and close the global inventory of marine plastics, which in turn represents critical information for mitigation or policy strategies. At the same time, plastic is a unique tracer that provides an opportunity to learn more about the physics and dynamics of our ocean across multiple scales, from the Ekman convergence in basin-scale gyres to individual waves in the surfzone. In this review, we comprehensively discuss what is known about the different processes that govern the transport of floating marine plastic debris in both the open ocean and the coastal zones, based on the published literature and referring to insights from neighbouring fields such as oil spill dispersion, marine safety recovery, plankton connectivity, and others. We discuss how measurements of marine plastics (both in situ and in the laboratory), remote sensing, and numerical simulations can elucidate these processes and their interactions across spatio-temporal scales.

/pdf/the-physical-oceanography-of-the-transport-of-floating-32bmq1tv9q.pdf

The physical oceanography of the transport of floating marine debris

/pdf/environmental-signal-propagation-in-sedimentary-systems-1b112erb2e.pdf

Environmental signal propagation in sedimentary systems across timescales

Development and validation of a three-dimensional morphological model

This thesis presents the development and validation of a novel three-dimensional sediment transport and morphological numerical model suitable for coastal regions. The thesis discusses the modelling of both suspended and bed-load transport of non-cohesive sediment, important aspects of the morphological updating scheme, and approaches used to model the three-dimensional effects of waves on coastal hydrodynamics. Results of several validation studies are presented and the model is shown to perform well in several theoretical, laboratory, and full scale test cases. Application of the model and acceleration techniques to the complex and dynamic entrance to Willapa Bay, WA, USA is also critically analysed and discussed. A new method to select a representative morphological tide for coastal environments containing significant diurnal tidal energy is presented.

An approach to medium-term coastal morphological modelling

/pdf/on-line-sediment-transport-within-delft3d-flow-499v0x3f62.pdf

On-line sediment transport within Delft3D-FLOW

A process-based model is compared with field measurements to test and improve our ability to predict nearshore morphological change at seasonal time scales. The field experiment, along the dissipative beaches adjacent to Grays Harbor, Washington USA, successfully captured the transition between the high-energy erosive conditions of winter and the low- energy beach-building conditions typical of summer. The experiment documented shoreline progradation on the order of 20 m and as much as 175 m of onshore bar migration. Significant alongshore variability was observed in the morphological response of the sandbars over a 4 km reach of coast. A detailed sensitivity analysis suggests that the model results are more sensitive to adjusting the sediment transport associated with asymmetric oscillatory wave motions than to adjusting the transport due to mean currents. Initial results suggest that alongshore variations in the initial bathymetry are partially responsible for the observed alongshore variable morphological response during the experiment.

Modeling Nearshore Morphological Evolution at Seasonal Scale

Vessel motion data have many uses including seakeeping, vessel response model validation, under-keel clearance and cargo studies. However accurate measurements using survey-grade DGPS equipment on ships of opportunity can be hazardous for both the instruments and the personnel attending them in extreme weather conditions. These are frequently the very conditions for which the measurements are most desirable. For waterway-specific investigations where particular conditions are targeted, a portable, robust and easy to set-up/dismount solution is required to opportunistically measure vessel motions when conditions of interest occur. This paper describes OMC International's development and implementation of such a device for full scale vessel motion data collection, the “iHeave” vessel motion recorder. The OMC iHeave is a carry-on, set-and forget device for the accurate recording of short-duration vessel motions. Originally designed for use by marine pilots for an under-keel clearance study at the "Graveyard of the Pacific" Columbia River Bar, the iHeave is simple to use and self-contained. It can be rapidly mounted inside the bridge of almost any vessel while underway and requires no additional cabling or connections. At the time of writing some 32 winter transits over the Columbia River Bar have been measured by the Bar Pilots using an OMC iHeave device. Based on IMU technology (solid state accelerometers and gyroscopes), the iHeave measures and records all 6 degrees of motion (roll, pitch, yaw, surge, sway and heave) experienced by a vessel with accuracy comparable to the more traditional DGPS based approach.

Giles Lesser

Papers

Development and validation of a three-dimensional morphological model

An approach to medium-term coastal morphological modelling

On-line sediment transport within Delft3D-FLOW

Modeling Nearshore Morphological Evolution at Seasonal Scale

Measuring vessel motions using a rapid-deployment device on ships of opportunity