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A floating boom designed by a Dutch inventor to catch a huge island of floating plastic in the Pacific Ocean is now working.
Key points:
- The floating boom travels along ocean currents at the same speed of floating plastic, while a surface anchor slows the boom down to allow it to catch plastic
- The boom is being deployed at the Great Pacific Garbage Patch, an area of floating plastic rubbish twice the size of Texas
- The news follows a number of setbacks for the project
Boyan Slat, a university dropout who founded The Ocean Cleanup not-for-profit, announced the floating boom was skimming up waste in the ocean between California and Hawaii, with sizes ranging from a discarded net and a car wheel complete with tyre, to chips of plastic measuring just 1 millimetre.
After a number of initial setbacks, the results were promising enough to begin designing a second system to send to the Great Pacific Garbage Patch, an area of floating plastic rubbish twice the size of Texas, Mr Slat said.
But he sounded a note of caution, saying: "If the journey to this point taught us anything it is that it's definitely not going to be easy."
Our ocean cleanup system is now finally catching plastic, from one-ton ghost nets to tiny microplastics!
Also, anyone missing a wheel?
Also, anyone missing a wheel?
The floating boom with a tapered, three-metre-deep screen is intended to act like a coastline, trapping some of the 1.8 trillion pieces of plastic scientists estimate are swirling in the patch, while allowing marine life to safely swim beneath it.
Ocean Cleanup describes the boom as a passive system, which floats along natural oceanic forces to catch and concentrate the plastic.
Both the plastic and the boom are carried by the wind, waves and current at the same speed. To catch the plastic, a difference in speed is needed, so a surface sea anchor (an underwater parachute) is used to slow the boom down and catch the quicker-moving plastic.
After it was towed out to sea last year, the barrier did not catch any rubbish in its first weeks of operation because it was moving at the same speed as the plastic, prompting the introduction of the underwater parachute.
Late last year, the barrier broke under the constant pummelling by wind and waves in the Pacific, requiring four months of repairs before being relaunched from Vancouver in June.
The system also experienced a problem with "overtopping" — waves that pushed the plastic over the line of floating corks that hold the screen. That was solved by using a line of larger corks to corral the plastic.
The organisation wants to continue developing the plastic traps, scale them up and deploy more to the Pacific so they can gather thousands of tonnes of plastic each year. However, Mr Slat did not say when the second version would be ready for launch.
Mr Slat's organisation is one of a handful of groups working to collect rubbish from the open oceans.
There is more than enough to keep them busy.
It is estimated that between 600,000 and 800,000 metric tonnes of fishing gear is abandoned or lost during storms each year in the oceans, according to the Trash Free Seas Program at Ocean Conservancy, a non-profit environmental-advocacy group.
Photo:
Crew members sift through the plastic collected by the floating boom. (AP: The Ocean Cleanup)
Another 8 million metric tonnes (approximate) of plastic waste, including plastic bottles, bags, toys and other items, flow annually into the ocean from beaches, rivers and creeks, according to experts.
Mr Slat said the next move was to scale up the device and make it stronger, so it could stay at sea for longer and hold onto all the plastic it collected for a year or more before a ship retrieved the rubbish.
Summarising, he said: "There's a lot of work still ahead of us."
ABC/AP
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