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Place 06 · The North Pacific Garbage Patch · Wrap-up
Everybody’s Ocean
Nobody owns the water the patch floats in, and yet it is made of everybody’s stuff. Here is how the whole thing fits together, and who is trying to do something about it.
About 20 minutes · 1 video · a full practice review of the whole garbage patch
Look back
Seven chapters ago you did not know this
You can now
Find the soup
The patch is not an island: about 1.8 trillion pieces, 94% of them microplastics, over an estimated 1.6 million km². By weight, lost fishing nets are at least 46% of it.
You can now
Climb the hill
Trade winds and westerlies push surface water 90° to the right, into the middle of the gyre, building a hill up to about a meter high. Geostrophic flow carries the water around it, and floating things stay trapped on top.
You can now
Ride the loop
The Kuroshio is the fast, narrow western side; the California Current the slow, wide eastern one. Bath toys, sneakers and tsunami debris showed where the loop goes.
You can now
Fill the tub
Residence time is amount ÷ rate. Plastic does not go away: sunlight makes it brittle and waves break it into ever smaller pieces, and nobody really knows how long a bottle lasts.
You can now
Mind the net
Mesh size, tow depth, wind and where you draw the edge all change the answer. The patch is both twice the size of Texas and less than one piece per square meter.
You can now
Check the menu
Small fish, albatrosses and turtles eat plastic, while neuston animals and coastal rafters from Japan live on it. The same currents gather them all.
You can now
Read the map
Territorial sea to 12 nautical miles, EEZ to 200, high seas beyond. MARPOL bans dumping from ships, the High Seas Treaty took effect in 2026, and a plastics treaty is still being negotiated.
Photos: Alfo Medeiros, Richard REVEL, Oleksiy Yeshtokyn,🌻🇺🇦🌻, Erik Mclean, Mike van Schoonderwalt, Demian Tejeda-Benitez, Lea Guerette / Pexels
One more thing
Who decides what happens next?
National Geographic — How We Can Keep Plastics Out of Our Ocean. Three minutes on turning down the faucet instead of just mopping the floor.
The patch by the numbers
- 1.6 million km² — estimated area of the Great Pacific Garbage Patch (Lebreton et al. 2018), holding at least 79,000 tonnes of plastic
- 1988 — year MARPOL Annex V took effect, banning ships from dumping plastic anywhere at sea
- January 2026 — the High Seas Treaty took effect, covering the ocean beyond every country’s 200-nautical-mile zone
- 1,000+ — rivers that together carry about 80% of the plastic rivers deliver to the ocean (Meijer et al. 2021)
Nobody owns the high seas, but they are not lawless. Since 1988, MARPOL Annex V has banned ships from dumping plastic anywhere at sea. The High Seas Treaty took effect in January 2026, giving countries their first way to create protected areas out there, although it is not a plastics law, and talks on a global plastics treaty that began in 2022 are still going as of September 2026. Meanwhile, The Ocean Cleanup tows barriers through the patch and estimates a full cleanup would cost about $7.5 billion over ten years, while many scientists point out that the faster fix is upstream: more than 1,000 rivers carry 80% of the plastic that rivers bring to the sea, and fishing gear makes up most of the patch’s larger plastic. The patch took decades to build, and it will take decades to shrink. That is residence time, not doom.
Figures: Lebreton et al. 2018 (The Ocean Cleanup), International Maritime Organization, United Nations and NOAA Marine Debris Program.
Two pictures to take with you
What we pull out, and where it all fits
Put it all together
Garbage Patch Review
Seven chapters, one garbage patch. This review walks the whole place, from the wind that builds the hill to the treaties on the high seas, with a few questions that tie it back to the places before it. Retry as often as you like. If one trips you up, the feedback names the chapter to revisit, and every chapter has its own eight-question practice set at the bottom of the page.
Practice
Garbage Patch Review: the whole place
Twenty questions: two from every chapter, three about who decides what happens next, and three that tie the chapters, and the earlier places, together. Retry as often as you like; the feedback is where the learning is.
Where we go next
Next stop: The Northeast Coast
One place left, and it is the closest to home. The Gulf Stream, the Kuroshio’s Atlantic twin, races north past the coast from Delaware Bay to Maine and runs into cold water coming down from Labrador. That collision feeds cod, lobsters and right whales, and the rivers that drain New York push fresh water out to meet the salt. It has also turned the Gulf of Maine into one of the fastest-warming patches of ocean on Earth. Bring the gyre with you; you will need it.
Photo credits (Pexels): Zelch Csaba, Nhi Tran, Amar Preciado.
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