The Age of Discovery, when European ships sailed the oceans in search of new trading routes and partners, finding previously unknown lands along the way, ended in the 17th century. By the early 1900s, intrepid explorers had mapped out the remote interiors of Australia, Africa and Antarctica, and these days, even the most rotund of tourists can waddle around what were once remote wildernesses. Modern technology has made the world a very small place indeed.

How surprising, then, that a mere 12 years ago, American sea captain Charles Moore should ‘discover’, in the North Pacific, a previously uncharted region twice the size of France.

Moore didn’t stumble upon some amazing (Pacific) Atlantis, but a more sinister byproduct of modern technology: the ‘Great Pacific Garbage Patch’. He wrote: “There were shampoo caps and soap bottles and plastic bags and fishing floats as far as I could see. Here I was in the middle of the ocean, and there was nowhere I could go to avoid the plastic.” The phenomenon is commonly thought of as an ‘island’ stretching 500 nautical miles, but the label is a misnomer. The North Pacific Subtropical Gyre is more of a ‘soup’, the ocean saturated with countless bits of plastic that look like confetti (or, if you’re a marine animal, plankton), along with occasional larger objects. On their research visit last year, the crew of Captain Moore’s ship explained on their blog: “It really is difficult to comprehend the vastness of this phenomenon. There is still a common public misconception that the gyre is a ‘place’, a detectable spot, when rather it is an enormous, extremely diffuse region.”

Debris converges in the gyre because of a slowly moving spiral of currents formed by a high-pressure air system. Estimates suggest that 80 per cent of the rubbish originates on land and 90 per cent of it is plastic. And though plastics on solid ground appear stable – even eternal – in the ocean they’re anything but. For one thing, they’re subject to ‘photodegradation’, a process where ultraviolet radiation breaks polymer molecules into shorter segments and weakens their strength, resulting in the tiny bits of plastic that constitute most of the ‘soup’. Moreover, scientists have recently discovered that in open ocean conditions, plastics degrade relatively quickly and release potentially toxic chemicals, including bisphenol A, linked with hormone disruption, and styrene monomer, a potential carcinogen. And that’s not all there is to worry about: Plastics absorb hydrophobic substances like fertilizers and herbicides, which can enter the food chain when marine life mistakes plastic for sustenance.

Although the ‘garbage patch’ was discovered over a decade ago, it has only recently become notorious with the wider public, in large part because of some high-profile expeditions to the gyre. Captain Moore’s Algalita Marine Research Foundation sponsored the voyage of the ‘Junk Raft’, a 30-foot vessel built from 15,000 plastic bottles, salvaged sailboat masts and a Cessna aeroplane fuselage. Last summer, Junk Raft sailed from California to Hawaii ‘to raise awareness about plastics fouling our oceans’.

Moreover, David de Rothschild has thrown the weight of his name and money from international sponsors into a project that will send a boat through the ‘garbage patch’ on a trip from San Francisco to Sydney. The ‘Plastiki’, named in honour of the ‘Kon Tiki’ raft on which Thor Heyerdahl crossed the Pacific in 1947, will be a 60-foot catamaran made from 12,000 reclaimed plastic bottles, srPET (woven fibres of PET with similar properties to fibreglass) and other reclaimed plastics. Its crew aims ‘to beat waste by inspiring sustainable solutions and to highlight the ecological damage being done to the world’s oceans’. But safe and sustainable solutions are not easy to come by: The Plasitiki’s launch date has been postponed from April 2009 until ‘the end of 2009’.

Both admirable stunts aim to raise awareness of the problem in the hopes that people will better manage their waste and stop using oceans as dumping grounds. Doubtless this is the most significant potential outcome of any trip to the gyre, but even if we prevented all the plastics currently in use on dry land from ever reaching the waters, there would still be an estimated 3,000,000 tonnes of unsightly, hazardous plastic in the Great Pacific Garbage Patch alone.

Captain Moore has claimed: “Trying to clean up the Pacific gyre would bankrupt any country and kill wildlife in the nets as it went.” Despite the logic of this statement, at least two projects are forging ahead, hypothesising and testing out collection and reprocessing techniques to use on the debris in the gyre.

Richard Sundance Owen, an American scuba instructor, founded the Environmental Cleanup Coalition and tasked engineer Jim Murosako with an ‘impossible project with an absurd timeframe’: to (quickly) design and deliver a system to clean up the gyre. Murosako’s solution, perhaps counter-intuitively, is to add more plastic to the gyre in the form of large pods in which plastic bits
can accumulate.

The Pelagic Pod (or P-Pod) is a barrel-shaped HDPE construction that will be anchored to allow the gyre’s currents to push the plastics into the container. Murosako explains: “There’s a sort of clover-leaf system of turbulence and stagnation and where it’s stagnant, the plastic’s naturally allowed to float up into chambers and ultimately into the containment section of the pod.”

Rather than being brought back to land for reprocessing, the plastic will be left in the sea because, as Murosako puts it: “If you have plastic in a container and have it still interacting with water, but reduce or eliminate interaction with marine life, the plastic that is absorbing hydrophobic chemicals becomes a chemical scrubber and cleans up the ocean. Also, these pods will naturally start to accumulate biomasss – algae, barnacles – which will protect the structure from degradation, naturally sequester carbon dioxide and increase the base of the marine food chain.” As for the harmful chemicals plastics release, Murosako claims: “In subsequent development, we’ll incorporate whatever is required to reduce the out gassing of those chemicals.”

Though the launch of the prototype has just been delayed until next spring, Owen and Murosako envisage a time when “there are tens of thousands to hundreds of thousands of self-propelled, autonomous pods out there creating an organic oasis in the desert that is the centre of the gyre.” It is not yet clear where funding will come from, but Owen is optimistic: “We are on the edge of worldwide recognition, and funding from countries and large corporations will be forthcoming soon.”

The Bureau of International Recycling, meanwhile, has already backed an expedition to the gyre by another group, Project Kaisei. Doug Woodrig, cofounder of the project, believes a successful cleanup mission must be driven by both environmental and commercial motives. Two Project Kaisei ships recently journeyed to the gyre to study debris and assess potential retrieval and processing techniques for different kinds of rubbish.

For ‘ghost nets’ (clumps of derelict fishing gear), Woodrig says: “You just need a crane to get those onto a boat and, ideally, someone will put a bounty on them so fishermen can be paid to bring them in… We’ve sent some to Korea to be melted down and rewoven into clothing material.” As for the large, intact plastic products like buoys, Woodrig says: “We’re looking at different netting methods, sea-anchored systems that wouldn’t use a lot of energy. Debris doesn’t move, so you can have very large, fence-like systems that don’t enclose anything until you go along and pick things up.” The collected plastic could be then turned into fuel or otherwise recycled.

Woodrig admits the smaller pieces of photodegraded plastic pose a bigger problem, but claims: “We’re working on some devices where the water will lap over something and the marine life can escape, but the little plastic bits will just float into a different holding area.”

Once captured, these bits can also be converted to fuel: Plastics expert Ed Kosior has developed a system to turn ocean-based plastic waste into a liquid diesel fuel. The system uses low heat and no oxygen and, Kosior says, can be used very successfully on different polymers, regardless of their condition. He adds: “Initially, this would be done on a land-based system and when the volumes are justified, you could then see if you could do it on a ship-based system.” Kosior cautions, however, that collecting this material “is going to be very difficult and very expensive and have a huge carbon footprint”.

Project Kaisei will shortly release a white paper of scientific findings and, Woodrig says, is “planning to go on another expedition next summer to work on some of our catch techniques so we can expand them and scale them up.”

Most of the rubbish accumulating in the North Pacific Subtropical Gyre originated in the US and Japan, so it is perhaps tempting – from a European perspective – to think of it as someone else’s mess. However, the North Pacific Subtropical Gyre is just one of five major oceanic gyres, the others of which could likewise create vortexes for rubbish. So it seems a new Age of Discovery may well be upon us, but humans, as creators of the problem, must ensure that any revelation of further oceanic ‘garbage patches’ is matched by inventions of systems to both clean and, more importantly, prevent contamination.