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The deepest parts of our sea are seen as unreachable as outer space, but plastic might be more determined to explore the farthest reaches of our planet than even people.

“It’s very lunar,” James Cameron said about the seafloor of Mariana Trench, the deepest part of the ocean. “You don’t expect a profusion of life.” Only three people have ever reached the bottom of the 36,000 foot deep trench, but in 2018, it was discovered that in 1998 ROV KAIKO observed a single-use plastic bag in Mariana Trench. Tons (literally) of plastic are put into the ocean every year, confusing animals searching for prey and introducing foreign chemicals into the ecosystem. On the surface, plastic floats and accumulates in ocean gyres in garbage patches—the largest patch in the Pacific Ocean being twice the size of Texas. Over time though, larger macroplastic breaks down into smaller and smaller pieces, microplastic, and accumulates throughout the water column and eventually sinks to the seafloor.

  • How do you think plastic ended up so deep in the ocean?
  • How does plastic impact marine life and ecosystem function?
  • What steps can you take as an individual to reduce plastic waste?
  • What can we do as a nation or as an international community?

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Human Transportation

Though 80% of ocean plastic is sourced from land, 20% is caused by direct dumping from transport vessels. This dataset shows different types of human transportation, including ship travel in blue.

Marine Debris

This short film shows the sources and eventual terminus for manmade pollution in gyres known as garbage patches the ocean.

Ocean Drain (with gray bathymetry)

This dataset shows the depth of the ocean floor through a modeled "drain" of the ocean. The Mariana Trench is the deepest point of the world's oceans, southeast of Japan next to the Philippine Sea. Seeing that plastic has reached even the deepest part of the ocean—so deep that you could put Mount Everest in it—students get a sense of the scope of ocean pollution that adds complexity to the sea surface pollution described in the previous videos.