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Hank tells us about the enormous concentrations of plastic debris floating around in the Pacific Ocean, why they're there and why they're a problem.

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You know those plastic stickers that they put on apples?  What do you do with that sticker; do you always walk it over to a trash can, or do you just kind of flick it off onto the floor of your car where it ends up stuck to your shoe, and then tracked onto the street, and then maybe when it rains it finds its way down the sewer grate and onto a stream and then a river, and then the ocean, where it bobs along until it meets all its little plastic brothers and sisters, at the Great Pacific garbage patch.
Well now, hopefully you feel sufficiently guilty and will watch the rest of this episode.

A lot of our trash hangs out in the North Pacific, in an area called the North Pacific Gyre.  A gyre is a big system of ocean currents that collide to form a kind of vortex.  The North Pacific Gyre is one of the biggest, and it's also considered one of the world's largest ecosystems, because A) it's twenty million square kilometers, and B) because living things congregate there, some because they literally can't swim out of it, and others because the gyre's where all the action is, it's like a giant ocean corral.

But not only does it corral plants and animals, it also corrals trash.  The North Pacific Gyre bears the illustrious distinction of also being the world's largest landfill, except that it's not on land.

Now, whenever I talk to people about the garbage patch they seem to imagine it as like a giant Texas-sized floating island of trash.  But that's not what it is.  If it were, it would be a lot easier to study, and a lot easier to clean up.  Instead, the patch is actually two huge areas with high concentrations of trash suspended in the water on the East and West sides of the gyre.

The size of the area and the changing nature of the ocean makes it really hard to study, but there's at least 100 million tons of trash in the Gyre.  And that number can literally only increase.  See, a lot of our garbage these days is not biodegradable, meaning that microbes that break down other kinds of refuse can't eat it.

The plastics make their way out into the North Pacific, and then they start to photodegrade, as the sunlight weakens the bonds in the plastic polymers, breaking them into smaller and smaller bits and leaching chemicals like Bisphenol A into the water.  But though the energy of the sun is good at breaking stuff down, the stuff never disappears entirely.  So we end up with microscopic bits of it suspended in the water column, over hundreds and hundreds of miles of ocean.

About 80% of this trash comes from land via powerful ocean currents that act as trash super highways, but the rest comes from offshore oil rigs and commercial fishing and cargo ships.  In fact, about 10% of the trash in the North Pacific is just free-floating fishing nets.  Because what happens when you got a bunch of fishing nets floating around on the high seas?  This.  And this makes me very sad.  Turns out that the combination of one of the largest ecosystems on Earth and a bunch of floating trash is not awesome; sea turtles and other animals get entangled in the nets, dead birds are being found with bellies full of gaskets and apple stickers.  Plus, chemicals in the plastics make their way into the food chain and cause all kinds of problems for marine life.

So yeah, not ideal.  As for what you can do, start out by, like, putting your trash in the trash, even if it's just an apple sticker.
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