Great Pacific Garbage Patch is a collection of in the North Pacific Ocean. Marine debris is litter that ends up in oceans, seas, and other large bodies of water.
The Great Pacific Garbage Patch, also known as the Pacific trash vortex, spans waters from the West Coast of North America to Japan. The patch is actually comprised of the Western Garbage Patch, located near Japan, and the Eastern Garbage Patch, located between the U.S. states of Hawaii and California.
These areas of spinning debris are linked together by the North Pacific Subtropical Convergence Zone, located a few hundred kilometers north of Hawaii.
This convergence zone is where warm water from the South Pacific meets up with cooler water from the Arctic. The zone acts like a highway that moves debris from one patch to another.
The entire Great Pacific Garbage Patch is bounded by the North Pacific Subtropical Gyre. An ocean gyre is a system of circular ocean currents formed by the Earth’s wind patterns and the forces created by the rotation of the planet.
The North Pacific Subtropical Gyre is created by the interaction of the California, North Equatorial, Kuroshiro, and North Pacific currents. These four currents move in a clockwise direction around an area of 20 million square kilometers (7.7 million square miles).
The area in the center of a gyre tends to be very calm and stable. The circular motion of the gyre draws debris into this stable center, where it becomes trapped.
The amount of debris in the Great Pacific Garbage Patch accumulates because much of it is not biodegradable. Many plastics, for instance, do not wear down; they simply break into tinier and tinier pieces.
For many people, the idea of a “garbage patch” conjures up images of an island of trash floating on the ocean. In reality, these patches are almost entirely made up of tiny bits of plastic, called microplastics. Microplastics can’t always be seen by the naked eye.
Even satellite imagery doesn’t show a giant patch of garbage. The microplastics of the Great Pacific Garbage Patch can simply make the water look like a cloudy soup. This soup is intermixed with larger items, such as fishing gear and shoes.
The seafloor beneath the Great Pacific Garbage Patch may also be an underwater trash heap. Oceanographers and ecologists recently discovered that about 70% of marine debris actually sinks to the bottom of the ocean.
No one knows how much debris makes up the Great Pacific Garbage Patch. The North Pacific Subtropical Gyre is too large for scientists to trawl. In addition, not all trash floats on the surface.
Denser debris can sink centimeters or even several meters beneath the surface, making the vortex’s area nearly impossible to measure.
About 80% of the debris in the Great Pacific Garbage Patch comes from land-based activities in North America and Asia. Trash from the coast of North America takes about six years to reach the Great Pacific Garbage Patch, while trash from Japan and other Asian countries takes about a year.
The remaining 20% of debris in the Great Pacific Garbage Patch comes from boaters, offshore oil rigs, and large cargo ships that dump or lose debris directly into the water.
The majority of this debris—about 705,000 tons—is fishing nets. More unusual items, such as computer monitors and LEGOs, come from dropped shipping containers.
While many different types of trash enter the ocean, plastics make up the majority of marine debris for two reasons. First, plastic’s durability, low cost, and malleability mean that it’s being used in more and more consumer and industrial products. Second, plastic goods do not biodegrade but instead break down into smaller pieces.
Marine debris can be very harmful to marine life in the gyre. For instance, loggerhead sea turtles often mistake plastic bags for jellies, their favorite food.
Albatrosses mistake plastic resin pellets for fish eggs and feed them to chicks, which die of starvation or ruptured organs. Marine debris can also disturb marine food webs in the North Pacific Subtropical Gyre.
As microplastics and other trash collect on or near the surface of the ocean, they block sunlight from reaching plankton and algae below.
Algae and plankton are the most common autotrophs, or producers, in the marine food web. Autotrophs are organisms that can produce their own nutrients from oxygen, carbon, and sunlight.
If algae and plankton communities are threatened, the entire food web may change. Animals that feed on algae and plankton, such as fish and turtles, will have less food.
If populations of those animals decrease, there will be less food for apex predators such as tuna, sharks, and whales. Eventually, seafood becomes less available and more expensive for people.
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