Where is the plastic in the ocean? And where exactly is it coming from?

Ocean plastic has, in a pretty short time, become a surprisingly potent international environmental movement.

For one, there’s more awareness now about the astounding quantity of plastic — between 4.7 and 12.8 million metric tons — floating around in the ocean. As the World Economic Forum put it, this volume is “equivalent to dumping the contents of one garbage truck into the ocean per minute.”

Garbage patches the size of small countries floating on the surface of the ocean have become another powerful image of the problem, as have photos and videos of marine life choking on and filled with plastic.

In the past couple of months, we’ve also seen a major mobilization around keeping plastic out of the ocean. “Beat Plastic Pollution” was the focus of UN World Environmental Day on June 5, inspiring hundreds of beach cleanup events around the world and a remarkable commitment from India to ban single-use plastics by 2022.