THEREare five major gyres in the oceans worldwide,three of which come in close proximity to the African continent.
A gyre is alarge system of slowrotatingocean currents - almost like a whirlpool - whichcircles large areas of stationary water, this is where the extent of the massive pollution problem becomes apparent.Debris picked up by the currentsdrifts into these stationaryareas and, due to the lackof movement in the water, canaccumulatefor years.
These areas are called garbage patches.The Indian Ocean, North Atlantic Ocean, and North Pacific Ocean all havesignificantgarbage patches. Unfortunately, according to the 5 Gyres ResearchInstitute,about 90%of the debris in all thegarbage patches is plastic.
The word patch in reference to these gigantic areas of devastating pollution doesnt do justice to the sheer size of the problem.
To put their mass into perspective one ofAfricas closest garbage patches is theIndian Ocean garbage patch,discovered in 2010byMarcus Eriksen - a marine scientist and founder of the5 Gyres Institute - andhis crew. Itcomprises an area ofat least five million square kilometres in size, but with no clear boundaries. Thats larger than South Africa and Ethiopia combined.
Eventually, the debris which has become trapped at the centre of the gyre, breaks down into a kind of plastic soup because in the ocean, sunlight and waves cause floating plastics to break into increasingly smaller particles, but theynever completely disappear or biodegrade.
These tinyplastic particles are as small as the algae and plankton that form the basis of the entire ocean food web. Species such as shrimp, birds, and fish consume these micro-plastics, which will often kill them. The plastic chemicals can also be absorbed by predators of these species and work their way into human diets sincetheconcentration of these chemicals increases through eachtrophic level of the food chain. The effects are toxic with health effects ranging fromcancer tomalformation and impaired reproductive ability.
These garbage patches have already haddevastating impacts onthe fishing and tourismindustries in many parts of the world which are affected economically by plasticentering nets, damaging propellers and other equipment, and washing up onbeaches.
In this image, scuba divers are removing an agglomeration of nets from a reef, a debris pile that was swept together in the North Pacific Gyre.(Photo/NOAA/NMFS/OPR/Flickr).
Fixing the problem
Garbage patches generally accumulate far fromany countrys coastline meaning, it is nearly impossible to track where it came from, and thereforefewnations have accepted theresponsibilityof cleaning them up.
The tiny plastic particles that make up most of the souppatches arealso very difficult andexpensivetodetectand remove.
Fortunately there is hope.
21-year-oldBoyan Slat is a Dutch entrepreneur and inventor who has created the worlds first ocean cleaning system whose pilot programme will be deployed in 2016 in Japan - specifically, atTsushima Island.
Instead of going after the plastic, Boyandevised a system through which, driven by the ocean currents, the plastic would concentrate itself, reducing the theoretical cleanup time from millennia to years.
The system, which involves a static platform that passively collects plastics when wind and ocean currents push debris to the 2000-meter booms, will be the longest floating structure ever deployed in the ocean. The plastic is then picked up by ships using a conveyor belt and there are plans underway torecycleit into biofuel.