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. The Great Pacific Garbage Patch is mostly tiny bits of plastic. These small pieces are called microplastics. They cannot always be seen. Often, they just make the water look like a cloudy soup. Larger things, like fishing nets or shoes, are mixed into this soup.
It doesn't get any better beneath the surface of the water. The seafloor under the Great Pacific Garbage Patch is an underwater garbage heap. Over time, most marine debris sinks to the bottom.
A lot of the debris in the Great Pacific Garbage Patch comes from fishing boats. Some also comes from distant cities and towns. Plastics are the most common kind of marine debris. Most of this debris comes from plastic bags, bottle caps, plastic water bottles and Styrofoam cups. The sun breaks these plastics into smaller and smaller pieces.
Even if they can't be seen, they are still there. Marine debris can be very harmful to marine life. For example, turtles often mistake plastic bags for jellies, their favorite food. Albatrosses mistake plastic pellets for fish eggs. They then feed the pellets to their chicks. Often, the chicks die. Seals are also in danger. They can get tangled in plastic fishing nets. Seals often drown in these nets.
Marine debris is affecting the entire food chain. For example, algae are underwater plants. Plankton are tiny critters that eat algae to survive. Plankton get eaten by other animals, like whales.
But microplastics stop sunlight from reaching underwater algae. Without sunlight, the algae won't grow and spread. Without algae, plankton won't have enough food. And without plankton, whales won't have any food either. Plastics also contain harmful pollutants. These dangerous chemicals are poisoning the water. They are also making fish and marine mammals, such as whales and seals, very sick.
Cleaning up marine debris is not easy. Invasive species might find it difficult to adapt to new environments and potentially disrupt the ecosystem and the local food web. Despite how small microplastics are, they can have devastating effects on the marine ecosystem, too.
Mircoplastics could also stunt sea plant growth, and the reproduction rates of species like zooplankton. Cleaning up the Great Garbage Patch should be a shared global responsibility, as it is an accumulation of waste collected from all coasts of the world. And considering the fact that plastics could take upwards of years to decompose and break down, the patch would not be going anywhere anytime soon.
Likewise, it is near impossible to track microplastics accurately, especially in deep water layers and the seafloor. However, satellite imagery has improved over the years that have allowed for meter-sized debris items to be identified.
NASA technology , primarily used for analysing wind speeds for hurricanes, can also be used to detect and track how some microplastics move, aiding efforts to clean up the sea. Ultimately, the best way forward is to prevent plastic waste entering our oceans in the first place, and to place stricter regulations on commercial fishing, controlling the amount of fishing nets that get left behind in the ocean. Each Share makes a difference and potentially gets our article in front of many times the number without shares.
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