Given the unprecedented nature of its mission, the Ocean Cleanup Project's trash-catching ventures were always going to include some unexpected twists and turns. With its first system entering service in the Great Pacific Garbage Patch one month ago, there are some good signs and some bad, including an apparent inability of the huge floating barrier to retain plastic trash for very long after it is caught.
Wilson, as the first trash-collecting system has been named, works like a Giant Pac-Man, harnessing the power of the currents, wind and surface waves to sweep across the sea. It consists of a giant floating barrier with a three-meter (10-ft) skirt dangling below, and because it will travel faster than the debris that is powered only by the ocean currents, it's hoped it will travel through the Great Pacific Garbage Patch scooping up plastic for removal by a support vessel.
But after its first month of observations, the Ocean Cleanup team has found that while the plastic is entering the system as expected, at least some of it is escaping after a relatively short time. Though the team is yet to pin down the source of problem, they see a couple of distinct possibilities. The system needs to travel faster than the plastic it is trying to collect, but it has been concluded that it is currently moving too slow, and at times is even outpaced by the plastic it is trying to catch.
This may be because the winds are causing oscillations at the ends of the u-shaped barrier, like the fin of a fish, which may be creating drag and slowing it down. Another possibility is that vibrations at the tips of the u-shaped barrier are creating a ripple effect, which could be pushing the plastic away from the mouth of the system.
So what do to? They team says its initial remedy will be to widen the mouth of the U-shaped barrier by 60 to 70 meters (200 to 230 ft), which is hoped to have a dual effect. It's hoped this will create a greater surface area for the wind and waves to propel the system along so it can reach greater speeds. Furthermore, hopefully this will also limit the effects of the ripple forces created by the flapping ends that may be pushing the plastic away.
And doing this is relatively simple, according to the team, as all it will take is a lengthening of the lines that hold the barrier in its u-shaped form. This will be done in several stages, beginning this week, until it has the desired effect. If it does not, then it will be back to the drawing board.
If it can get this first system running optimally, the Ocean Cleanup Project hopes to eventually deploy a fleet of its trash-collecting barriers in the Great Pacific Garbage Patch, which is believed to be around three times the size of France and hold as many as 1.8 trillion pieces of plastic. The team expects a fleet of 60 barriers could clean half of the Great Pacific Garbage Patch every five years.
You can hear from the team on these latest developments in the video below.
Source: The Ocean Cleanup Project
