The Mega Expedition
In late April, the Ocean Cleanup organization announced its somewhat audacious Mega Expedition project, in which “up to 50 vessels will collect more plastic measurements in three weeks than have been collected in the past 40 years combined.” The aim of this self-proclaimed “largest research expedition in history”? To create the first high-resolution estimate and map of plastic in the infamous Great Pacific Garbage Patch, a region in the Pacific Ocean that is home to one of the five global rotating currents called gyres. Estimates suggest that 1/3 of the millions of tons of plastic that enter the oceans each year ends up in this gyre, and the vessels that set sail in August from Hawaii will cover 3,500,000 km2 as they travel through the gyre in parallel paths toward California.
The CEO and founder of Ocean Cleanup is a young Dutchman named Boyan Slat. Last year Slat received the Champions of the Earth Award from the United Nations; the youngest ever winner of their top environmental award. While he may be the founder of Ocean Cleanup and its chief inventor, he is by no means toiling alone in this effort. Ocean Cleanup is supported by more than 15 institutions and companies, and over 100 volunteers–most of them scientists and engineers. Ocean Cleanup also ran an incredibly successful crowdsource funding campaign to which over 3000 people contributed.
There has been a great deal of progress in the past few years determining how much plastic is in the ocean and where it has concentrated. However, it is still not clear how much is entering from waste generated on land, and from where most of it is coming. Scientists have been working to answer these questions, and results from a recent study suggest that 275 million metric tons (MT) of plastic waste was generated in 192 coastal countries in 2010 alone, with 4.8 to 12.7 million MT entering the ocean. The Mega Expedition is an attempt to identify more clearly the scale of the plastic problem and provide a better estimate of the mass of plastics in the gyres for the primary objectives of the Ocean Cleanup organization. As critical as the expedition is, it is but one piece of the much larger Ocean Cleanup vision. As their name implies, they are interested in ridding the oceans of as much plastic marine debris as possible. Their goal is to “fuel the world’s fight against oceanic plastic pollution by initiating the largest cleanup in history.” Moreover, they are well on their way – having now developed and tested a feasible and cost-effective system to make it happen.
Slat’s invention is remarkably straightforward. While other proposals suggest energy intensive and cost-prohibitive methods of retrieving plastic with nets and ships, Slat devised a passive floating barrier system that uses the natural circulating power of the ocean currents to concentrate the plastic. Feasibility studies and computer modeling suggest that a single, 100-kilometre-long floating barrier in place for ten years would remove almost half of the plastic in the North Pacific Gyre. The “Ocean Cleanup Array” is configured in a V-shape with two 50-kilometre-long arms concentrating the plastic to a collection platform at the center. Solar panels will provide power, and it is expected that the 10,000 m3 platform will be emptied every six weeks. Most of the plastic is found within three metres of the surface and tests conducted in the Atlantic confirmed that plastic travels along the barriers. Ocean Cleanup is on schedule to start sea trials of the technology in 2016, and they hope to be full-scale within three or four years.
Prevention is an essential part of stopping plastic pollution, and Ocean Cleanup stresses that individuals, corporations and governments all have roles to play. Pollution can be prevented through changes in consumer habits, sustainable product design, preventing spillage by producers, and improved collection through better infrastructure. In addition, alternatives to plastic can be introduced, high-risk products can be banned, and recycling methods can be enhanced to improve the value of plastic as a raw material.
Is it possible to remove all the plastic from global oceans? No. But that doesn’t mean we can’t try, and we are certainly capable of reducing how much is entering the oceans from now on.
For more information visit the Ocean Cleanup website: https://www.theoceancleanup.com/
- Champions of the Earth, 2014. Retrieved from http://unep.org/champions/news/champions-of-the-earth-2014-boyan-slat-announced.asp#sthash.vfms1DyP.dpbs
- Jambeck et al., Plastic waste inputs from land into the ocean. Science 13 February 2015: Vol. 347 no. 6223 pp. 768-771. Abstract retrieved May 12, 2015 from http://www.sciencemag.org/content/347/6223/768.abstract