We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Langmuir turbulence in a depth-varying coastal channel: Insights from large eddy simulations
AI summary Read the abstract
Scientists studied how ocean waves create spinning water currents in coastal areas like bays and rivers, which help mix pollution and tiny plastic particles throughout the water. These wave-driven currents are much stronger than previously thought and significantly change how pollutants like microplastics spread through coastal waters where people swim, fish, and get drinking water. Understanding these mixing patterns is important for predicting where ocean pollution ends up and how it might affect human health.
This study investigates wave-driven Langmuir turbulence (LT) in an idealized, depth-varying coastal channel representative of an estuarine bay or tidal river. In the open ocean, LT is a key turbulent process in the surface boundary layer, controlling the transport and mixing of momentum and density. LT arises from wave-current interactions that generate wind-aligned vortices, often visible as surface windrows of aggregated buoyant material such as plankton, bubbles, oil, and microplastics. To examine how LT influences the wind-, tide-, and density-driven circulation in a coastal channel, we develop a turbulence-resolving large eddy simulation (LES) framework with terrain-following coordinates representing a deeper central channel flanked by shallower margins. LT is generated through the Craik-Leibovich (CL) vortex force, which incorporates Stokes drift from wind-driven surface gravity waves. The simulations show that LT substantially enhances turbulent mixing, reducing vertical stratification and shear. Faster tidal currents in the deeper channel differentially advect salt, producing tidally varying lateral salinity gradients. These gradients generate baroclinically driven lateral and vertical tidal currents, whose development is both accelerated and intensified by LT. Conversely, vertical stratification and vertical shear of lateral currents can inhibit LT. Additionally, lateral shear of along‑channel currents associated with the channel bathymetry produces channel‑wide pairs of vertical vorticity that are tilted by Stokes‑drift shear, forming strong and persistent lateral circulations. Overall, the results reveal complex two‑way interactions between LT and the mean circulation, demonstrating that LT significantly modifies both tidally resolved and tidally averaged channel dynamics.
More Papers Like This
Particle clustering and dispersion in multi-scale Langmuir turbulence and regional flow convergence
AI summary Read the abstract
Researchers studied how ocean currents and wind-driven waves move harmful particles like microplastics through estuaries (where rivers meet the ocean), finding that these forces create narrow bands where pollution concentrates. Understanding how pollutants cluster in these specific areas matters because it helps scientists predict where people and wildlife are most exposed to dangerous microplastics and other contaminants in coastal waters.
Influence of waves on the three-dimensional distribution of plastic in the ocean
AI summary Read the abstract
Researchers modeled the trajectories of microplastic particles released continuously from coastal sources across realistic ocean simulations to understand how wave dynamics and ocean circulation distribute plastic pollution globally. The model showed that wave-driven mixing significantly influences vertical plastic distribution, not just horizontal surface drift. Including wave effects improves predictions of where ocean microplastics accumulate.
Wave-driven current and vortex patterns at an open beach: Insights from phase-resolving numerical computations and Lagrangian measurements
AI summary Read the abstract
This study analyzed wave-driven current and vortex patterns at an open beach using phase-resolved modeling, providing insights into nearshore hydrodynamics relevant to coastal plastic transport and accumulation patterns.
Large eddy simulations of the accumulation of buoyant material in oceanic wind-driven and convective turbulence
AI summary Read the abstract
Researchers used large eddy simulations to show that buoyant materials like microplastics accumulate at specific ocean surface zones driven by convergent currents under both wind-driven and convective turbulence, improving understanding of how plastics concentrate at the sea surface.
The Role of the Unsteady Surface Wave‐Driven Ekman–Stokes Flow in the Accumulation of Floating Marine Litter
AI summary Read the abstract
Researchers modeled the role of wave-driven Ekman-Stokes flow in the accumulation of floating marine debris, finding that this near-surface current mechanism significantly influences where plastic litter concentrates at sea, with implications for predicting and targeting ocean cleanup efforts.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.