Every year, the world produces over 300 million tonnes of plastic and around 35 million tonnes of plastic waste, of which only about 8 per cent is recycled. Much of the rest ends up in our oceans. In 1997, Captain Charles Moore of California stumbled upon a huge concentration of garbage in the Pacific Ocean south of San Francisco. It was held up by the media as a symbol of the global plastic pollution crisis.
It is easy to picture a massive island of floating debris in the middle of an ocean. One may also be able to estimate the clean-up cost, if the mess were amenable to such a calculation. Unfortunately, contrary to convenient media descriptions of a giant iceberg-like mass of garbage bobbing in the sea, the infamous Great Pacific Garbage Patch is hardly visible to the naked eye.
It does, however, exist. It lies deep in the North Pacific, around 1,600 km north of Hawaii. The result of a massive infusion of micro-plastics in sea water, it is about 100 metres deep, covers an area popularly believed to be the size of Texas, though nobody knows for sure, and changes shape and size depending on ocean currents.
It is not even a single dump. There is a western garbage patch towards Japan and a subtropical convergence zone of the two dumps in the north. The debris is gathered by gyres—massive ocean currents that spiral around a central point. There are five major subtropical oceanic gyres: the North and South Pacific Subtropical Gyres, the North and South Atlantic Subtropical Gyres, and the Indian Ocean Subtropical Gyre.
The so-called Pacific Garbage Patch keeps moving within the North Pacific Subtropical Gyre, which covers an estimated 18-23 million sq km, which is about thrice the area of the continental United States. And yes, there are similar garbage patches in the Atlantic, but even less is known about those.
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Given its dynamic nature, it is impossible to measure the Pacific Garbage Patch. Any chance of retrieving the trash is made doubly daunting by the fact that the floating plastic is mostly microscopic. While plastic does not biodegrade, it dries up under sunlight and disintegrates into tiny particles. Dredging it up from ocean water with a fine mesh is a Herculean task. In any case, such an attempt will also haul out tiny plankton, credited with half of all photosynthesis on earth.
Micro-plastic and plastic in different stages of photo-degradation pose a severe biological hazard, the real dimensions of which remain unknown. Fish and other marine species (including birds) are seen to eat plastic and other garbage, with effects that one can only guess at. It is estimated that at least half the individuals of certain marine reptile species are affected by plastic litter.
Plastic debris also accumulates pollutants such as polychlorinated biphenyls (PCBs), which shoots the toxin concentration up to a million times the level in clean seawater. In 2001, PCBs were banned as coolant fluids internationally. It would be disastrous if these pollutants were to be consumed by scavenging organisms and passed on to humans through seafood products.
Given the risk to marine ecosystems and human health, several attempts are being made to tackle the mess. Many voluntary organisations, including the International Coastal Cleanup, have been trying to reduce the garbage that is dumped offshore.
But none of these initiatives has been nearly as ambitious as Project Kaisei (‘ocean planet’ in Japanese), which was launched in 2009 to clean the gigantic Pacific patch, or at least a good part of it. The project was started by Mary Crowley, a veteran sailor and an expert in oceanic arts and science; George Orbelian, an avid surfer and marine designer; and Doug Woodring, an expert in environmental technology. They had a simple plan to tackle the Pacific mess without having to scout for enormous landfill sites: gather as much garbage from the ocean as possible, treat it for toxicity and produce fuel through pyrolysis (breaking down through heat and chemicals) to run the campaign’s clean-up boats.
But most experts have been sceptical of the project’s chances of success. Given that scanning just 1 per cent of the northern Pacific will take 68 ships a year, they argue, attempting a clean-up of even the highest garbage concentration areas may end up burning more fossil fuel than would be offset by the clean-up. Besides, dredging billions of tiny plastic particles would be enormously expensive and time-consuming.
However, a range of passive collection techniques have been tested by Project Kaisei’s team to zero in on the least invasive and energy-consuming methods that could be used for a large-scale clean-up. It has also been trying to identify the most sustainable method for converting marine plastic debris into fuel and other marketable derivatives. In 2009, the UNEP hailed the project as a ‘Climate Hero’. It also won recognition as a Google Earth Hero for its work on a video blogging voyage tracking system. In 2010, it became part of the Clinton Global Initiative, and Doug Woodring launched the Ocean Recovery Alliance for greater synergy.
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All those accolades notwithstanding, the magnitude of the problem may yet get the best of Project Kaisei. Many have suggested lately that the scale of the mission has overwhelmed the project’s initial enthusiasm for cleaning up the Pacific. Though voyages have continued, much of its recent focus has been on prevention of garbage accumulation. Last August, Crowley reported that Project Kaisei found tsunami debris floating in from Japan to the Pacific vortex and recommended that fishermen be incentivised to collect trash along the coast before it escapes to the outer sea. “I don’t know if it’s possible to clean up all of it,” said Crowley, adding that her team was now collaborating with the US Coast Guard. She later sought government help to take a factory ship to the Pacific Gyre, armed with technology to recycle plastic into fuel. The project continues.
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