We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Discrete multivariate probability distributions of microplastic settling/rising velocity in the marine environment
AI summary Read the abstract
This study derived discrete multivariate probability distributions to characterize the vertical settling and rising velocities of marine microplastics, accounting for the highly variable density, size, and shape properties of particles found in the ocean. Both standard and mass-weighted probability distributions were developed to capture the statistical behavior of microplastic vertical transport across realistic particle populations. The resulting parameterization provides a more physically realistic representation of microplastic vertical dynamics for incorporation into ocean transport models.
The settling/rising velocity is of key importance in the vertical distribution of microplastics in marine environment. It is generally parameterized with semi-empirical laws dependent on the density difference between particles and fluid, size and shape of the particle. However, these physicochemical properties are extremely variable, given the complex multitude of microplastics in the sea. Therefore, it is difficult to know the settling/rising velocity for all the particles in the sea. A multivariate probability distribution for the vertical settling/rising velocity of marine microplastics was thus derived. A discrete probability distribution and a discrete mass-weighted probability distribution of the settling/rising velocity was obtained. The results suggest that most microplastics, given the predominant contribution of sedimentation, may accumulate on the seabed or reside for long periods in the water column, confirming the hypotheses reported in literature. The velocity probability distribution is of essential use as an input in stochastic dispersion models to properly simulate the phenomenon and understand its influence and effects.
More Papers Like This
Influence of Settling/Rising Velocity on the Vertical Distribution of Microplastics in the Marine Environment
AI summary Read the abstract
Researchers used a three-dimensional Lagrangian dispersion model incorporating mean ocean currents and subgrid-scale turbulence to simulate the vertical distribution of microplastics in marine environments, assigning particles a spectrum of settling and rising velocities reflecting the diversity of microplastic sizes, shapes, and densities. Results showed that using a probability distribution of velocities rather than a single value substantially alters predicted vertical concentration profiles throughout the water column.
Catching the variety: Obtaining the distribution of terminal velocities of microplastics particles in a stagnant fluid by a stochastic simulation
AI summary Read the abstract
A stochastic simulation model was used to estimate the distribution of settling and rising speeds for microplastic particles of varying size, shape, and density in still water. Understanding how microplastics move through water columns is essential for predicting where they accumulate and how organisms are exposed.
Modeling Microplastic Transport in the Marine Environment: Testing Empirical Models of Particle Terminal Sinking Velocity for Irregularly Shaped Particles
AI summary Read the abstract
Researchers tested multiple drag models for predicting the terminal settling velocity of irregularly shaped microplastic particles in seawater, identifying three high-precision models and demonstrating that settling velocity is largely stable across ocean depths and independent of initial particle velocity, improving the accuracy of marine microplastic transport simulations.
On some physical and dynamical properties of microplastic particles in marine environment
AI summary Read the abstract
This study examined the physical and dynamical properties of microplastic particles in marine environments, using modeling to predict how particle shape, density, and size govern transport, dispersion, and accumulation patterns.
Microplastics segregation by rise velocity at the ocean surface
AI summary Read the abstract
This study modeled the competing forces of particle buoyancy and turbulent mixing that control the vertical distribution of microplastics in the ocean surface layer, finding that particle rise velocity is the key variable that segregates plastic types and determines how they distribute relative to surface and subsurface measurements.
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.