Throughout the world’s oceans, there are numerous regions known as ‘garbage patches’ where high concentrations of plastic trash have accumulated.

While it’s known that wind and ocean currents play a role in their movement, there has been much debate over the mechanism that causes them to form.

Now, researchers have developed a model that could help to explain the phenomenon, simulating the motion of small spherical objects floating at the surface.

While it’s known that wind and ocean currents play a role in the movement of garbage patches, there has been much debate over the mechanism that causes them to form. The map shows global plastic concentration

GARBAGE PATCHES Garbage patches are regions with high concentrations of marine debris, according to the NOAA. The form from rotating ocean currents called gyres, and are not actually ‘islands of trash,’ as commonly believed. These patches are mostly composed of microplastics, most of which are the remnants of larger pieces of plastic garbage that have been broken up by the sun, salt, wind, and waves. These microplastics are just 5 milimeters in size. Advertisement

The new study from researchers at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science and colleagues used data on currents and winds to simulate the debris’ movement.

Garbage patches are mostly composed of microplastics, most of which are the remnants of larger pieces of plastic garbage that have been broken up by the sun, salt, wind, and waves, according to the NOAA.

The team investigated data from both anchored buoys and those that have become unanchored – also known as undrouged.

This allowed them to track the accumulation of debris in five ocean gyres over 20 years.

They also considered the effects of water and wind-induced drag.

The map shows the density of debris after 1.5 years of evolution after the simulated ocean currents and reanalyzed wind

‘We found that undrogued drifters accumulate in the centers of the gyres precisely where plastic debris accumulate to form the great garbage patches,’ said lead author Francisco Beron-Vera.

‘While anchored drifters, which are designed to closely follow water motion, take a much longer time to accumulate in the center of the gyres.’

The study revealed that the accumulation of debris in subtropical gyres is occurring far too fast to be solely the result of converging trade winds.

Instead, they say inertial effects must be taken into account as well.

The team investigated data from both anchored buoys and those that have become unanchored – also known as undrouged. This allowed them to track the accumulation of debris in five ocean gyres over 20 years. Garbage in the Pacific Ocean is pictured

‘We show that the size and weight of the drifters must be taken into account to fully explain the accumulation,’ said Maria Josefina Olascoaga, a co-author of the study.

According to the researchers, the new model has a number of practical applications.

Along with helping to monitor garbage patches, it could also be used to track shipwrecks, airplane debris, sea ice, and pollution.

The most famous garbage patch is the Great Pacific Garbage Patch, but, there are many others as well, according to the NOAA.

These patches are constantly moving and changing in size, but as they’re mostly made of debris just five millimetres large, some can go completely unnoticed.