Next year, a 20-year-old inventor will begin trawling the world’s oceans to try to clean up plastic garbage patches–the sprawling clumps where most of the world’s 5 trillion pieces of plastic trash end up. But a new animation shows exactly how hard that task will be: As soon as some plastic is cleaned up, ocean currents will bring more to take its place.
The animation follows the general path that most trash–from tiny particles to buoys–takes in the ocean to land in one of a handful of patches.
Animators at NASA’s Science Visualization Studio based the video on a model of the ocean’s currents, which they’d already built into their system for another mesmerizing video called Perpetual Ocean.
The animators dropped some virtual particles into the model and watched what happened. “As a quick test, we distributed a bunch of particles evenly around the world and let the model’s time varying vector field move the particles around,” says Greg Shirah, the lead animator. “After several years of simulated time, many of the particles began to clump into slower moving gyres–also called garbage patches.”
Next, the team compared the virtual model to what happened in real life–not with ocean trash, because the scraps of garbage drift around untracked, but with buoys that the National Oceanic and Atmospheric Administration uses to chart data like ocean temperature and salinity. Because the buoys are tracked by satellite, it was possible to compare where they ended up to the virtual particles. Everything eventually went to the same giant floating dumps (In the video, the buoys were all “released” at the same time, so it’s easier to watch their progress; in real life, NOAA constantly adds new ones).
The animation doesn’t exactly model what happens to the plastic bottles, old toothbrushes, and other plastic junk that ends up in the ocean, especially as the trash degrades into tiny pieces. “Small plastic particles likely respond differently to ocean currents than drifter buoys due to varying sizes and densities,” says Shirah. But it’s possible to see the general journey our trash takes–and how the problem will keep happening unless we figure out a better way to recycle waste.