The Evolution of Plume Fronts in the Rhine Region of Freshwater Influence

The Rhine region of freshwater influence (ROFI) is strongly stratified, rotational, relatively shallow and has large tides, resulting in a dynamic field of fronts that are formed by multiple processes. We use a 3D numerical model to obtain a conceptual picture of the frontal structure and the processes responsible for generating this multiple...

Observations of Multiple Internal Wave Packets in a Tidal River Plume

Remotely sensed images document the occurrence of multiple packets of internal solitary waves (ISWs) in the Rhine River plume at the same time. We use a combination of field observations, and non-hydrostatic and hydrostatic modeling to understand the processes that lead to the generation and retention of multiple ISW packets within the Rhine...

The formation of turbidity maximum zones by minor axis tidal straining in regions of freshwater influence

This study investigates the influence of tidal straining in the generation of turbidity maximum zones (TMZ), which are observed to extend for tens of kilometers along some shallow, open coastal seas. Idealized numerical simulations are conducted to reproduce the cross-shore dynamics and tidal straining in regions of freshwater influence ...

Observations of internal waves in the near field of the Rhine River Plume

Wave Generation of Gravity-Driven Sediment Flows on a Predominantly Sandy Seabed

Wave-supported gravity flows (WSGFs) generate rates of sediment flux far exceeding other cross-shelf transport processes, contributing disproportionately to shelf morphology and net cross-shelf fluxes of sediment in many regions worldwide. However, the conditions deemed necessary for the formation of WSGF limit them to a narrow set of shelf...

Cross-shore stratified tidal flow seaward of a mega-nourishment

The Sand Engine is a 21.5 million m³ experimental mega-nourishment project that was built in 2011 along the Dutch coast. This intervention created a discontinuity in the previous straight sandy coastline, altering the local hydrodynamics in a region that is influenced by the buoyant plume generated by the Rhine River. This work...

The Influence of Tide and Wind on the Propagation of Fronts in a Shallow River Plume

In this study we used field data and radar images to investigate the influence of winds and tides on the propagation of tidal plume fronts. The measurements were collected in a shallow shelf region off the Dutch coast, 10 km north of the Rhine River mouth, and they clearly show the passage of distinct freshwater lenses and associated fronts...

Cross-shore transport of nearshore sediment by river plume frontal pumping

We present a new mechanism for cross-shore transport of fine sediment from the nearshore to the inner shelf resulting from the onshore propagation of river plume fronts. Onshore frontal propagation is observed in moorings and radar images, which show that fronts penetrate onshore through the nearshore and surf zone, almost to the waterline....

The impact of storms and stratification on sediment transport in the Rhine region of freshwater influence

We present measurements of along and across-shore sediment transport in a region of the Dutch coast 10 km north of the Rhine River mouth. This section of the coast is characterized by strong vertical density stratification because it is within the midfield region of the Rhine region of freshwater influence, where processes typical of the far...

Hydrodynamics in the mid-field plume region of the Rhine ROFI

River plumes, also regions of freshwater influence , are important features to understand because of their impact on the current structure, stratification and the transport of fine sediments, nutrients and contaminants. One important river plume is the Rhine ROFI. Prior studies have sought to understand far-field dynamics where cross-shore...

Near-bottom currents on the middle shoreface in the presence of the Rhine River plume

The South-Holland coast of the Netherlands undergoes the influence of the Rhine river plume released from the Rotterdam waterways. An experiment, STRAINS, was conducted to study the impact of the fresh water on the nearshore hydrodynamics and sand transport. As part of the experiment, an instrumented bottom frame measured the near-bed...