Marine debris concentrates in various regions of the North Pacific, not just in one area. The exact size, content, and location of the "garbage patches" are difficult to accurately predict. The name "Pacific Garbage Patch" has led many to believe that this area is a large and continuous patch of easily visible marine debris items such as bottles and other litter—akin to a literal island of trash that should be visible with satellite or aerial photographs.
This is not the case. While higher concentrations of litter items can be found in this area, much of the debris is actually small pieces of floating plastic that are not immediately evident to the naked eye.
Ocean debris is continuously mixed by wind and wave action and widely dispersed both over huge surface areas and throughout the top portion of the water column. It is possible to sail through "garbage patch" areas in the Pacific and see very little or no debris on the water's surface. 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.
In reality, these patches are almost entirely made up of tiny bits of plastic, called microplastics. 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. While oceanographers and climatologists predicted the existence of the Great Pacific Garbage Patch, it was a racing boat captain by the name of Charles Moore who actually discovered the trash vortex.
Moore was sailing from Hawaii to California after competing in a yachting race. Crossing the North Pacific Subtropical Gyre, Moore and his crew noticed millions of pieces of plastic surrounding his ship. 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 of the trash floats on the surface.
These percentages vary by region, however. A study found that synthetic fishing nets made up nearly half the mass of the Great Pacific Garbage Patch, due largely to ocean current dynamics and increased fishing activity in the Pacific Ocean. While many different types of trash enter the ocean, plastics make up the majority of marine debris for two reasons. Second, plastic goods do not biodegrade but instead, break down into smaller pieces. In the ocean, the sun breaks down these plastics into tinier and tinier pieces, a process known as photodegradation.
Most of this debris comes from plastic bags, bottle caps, plastic water bottles, and Styrofoam cups. 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. Seals and other marine mammals are especially at risk. They can get entangled in abandoned plastic fishing nets, which are being discarded largely due to inclement weather and illegal fishing.
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 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.
These dangers are compounded by the fact that plastics both leach out and absorb harmful pollutants. As plastics break down through photodegradation, they leach out colorants and chemicals, such as bisphenol A BPA , that have been linked to environmental and health problems. Conversely, plastics can also absorb pollutants, such as PCBs, from the seawater. These chemicals can then enter the food chain when consumed by marine life.
Many individuals and international organizations, however, are dedicated to preventing the patch from growing. Cleaning up marine debris is not as easy as it sounds. Many microplastics are the same size as small sea animals, so nets designed to scoop up trash would catch these creatures as well. Even if we could design nets that would just catch garbage, the size of the oceans makes this job far too time-consuming to consider. Many expeditions have traveled through the Great Pacific Garbage Patch.
Charles Moore, who discovered the patch in , continues to raise awareness through his own environmental organization, the Algalita Marine Research Foundation. During a expedition , Moore and his team used aerial drones, to assess from above the extent of the trash below. The drones determined that there is times more plastic by weight than previously measured. The team also discovered more permanent plastic features, or islands, some over 15 meters 50 feet in length. Scientists and explorers agree that limiting or eliminating our use of disposable plastics and increasing our use of biodegradable resources will be the best way to clean up the Great Pacific Garbage Patch.
Organizations such as the Plastic Pollution Coalition and the Plastic Oceans Foundation are using social media and direct action campaigns to support individuals, manufacturers, and businesses in their transition from toxic , disposable plastics to biodegradable or reusable materials.
This file is licensed under the Creative Commons Attribution 2. Quotable Captain "So on the way back to our home port in Long Beach, California, we decided to take a shortcut through the gyre, which few seafarers ever cross.
Fishermen shun it because its waters lack the nutrients to support an abundant catch. Sailors dodge it because it lacks the wind to propel their sailboats. In the week it took to cross the subtropical high, no matter what time of day I looked, plastic debris was floating everywhere: bottles, bottle caps, wrappers, fragments. Months later, after I discussed what I had seen with the oceanographer Curtis Ebbesmeyer, perhaps the world's leading expert on flotsam, he began referring to the area as the 'eastern garbage patch.
Strange Cargo When ships are caught in storms, they often lose cargo to the oceans. The following are just a few of the strange items that have washed up on shores:. Also called an alpha predator or top predator.
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