So what is the Great Pacific Garbage Patch?
The Great Pacific Garbage Patch (GPGP) is the largest of the five offshore plastic accumulation zones in the world’s oceans. It is located halfway between Hawaii and California. The term was coined by Charles J. Moore, returning home through the North Pacific Gyre after competing in the Transpac sailing race in 1997.
Plastic Accumulation
It is estimated that 1.15 to 2.41 million tonnes of plastic are entering the ocean each year from rivers. More than half of this plastic is less dense than the water, meaning that it will not sink once it encounters the sea. The stronger, more buoyant plastics show resiliency in the marine environment, allowing them to be transported over extended distances. They persist at the sea surface as they make their way offshore, transported by converging currents and finally accumulating in the patch.
Once these plastics enter the gyre, they are unlikely to leave the area until they degrade into smaller microplastics under the effects of sun, waves and marine life. As more and more plastics are discarded into the environment, microplastic concentration in the Great Pacific Garbage Patch will only continue to increase.
At the time of sampling there were more than 1.8 trillion pieces of plastic in the patch that weigh an estimated 80,000 tonnes.
Why Large Debris Matter
Because the plastics have bene shown to persist in this region, they will break down into smaller plastics while floating in the Great Pacific Garbage Patch. This deterioration in to microplastic is usually the result of sun exposure, waves, marine life and temperature changes. Mircoplastics have been discovered floating within the water surface layers, but also in the water column or as far down as the ocean floor. Once they become this small, microplastics are very difficult to remove and are often mistaken for food by marine animals.