In 2016, the Ocean Cleanup foundation used a Hercules C-130 aircraft to conduct an aerial survey of the region to refine its data and count larger pieces of plastic (greater than 50 centimeters).
The researchers collected 1,136,145 pieces of debris that weighed a total of 668 kilograms and was 99.9% plastic.
From that, the researchers estimated the area had at least 1.8 trillion pieces of plastic in the water, weighing 79,000 metric tons — with more arriving every minute of every day.
They estimated that 1.7 trillion pieces were microplastics, between 0.05 and 0.5 centimeters, but that 92% of the total plastic mass came from larger pieces.
Shockingly, they also estimated that 46% of the plastic mass was from lost fishing nets known as "ghost nets" that drift through the sea, ensnaring creatures and breaking into smaller bits of plastic.
The team also thinks the 2011 tsunami that hit Tohoku, Japan, could have added significantly to the mass of plastic.
This may vastly underestimate the amount of plastic in the area, both because the researchers measured only within the boundaries of the "patch" — not the full gyre — and because many others think there are far more microplastics deeper in the water.
While the foundation wants to push for a plan to clean up the plastic in the patch, many researchers think our best bet is stopping pollution from making it into the ocean in the first place.
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