There are about 150 million metric tons of plastic in the oceans and a further 8 million metric tons are added to the oceans annually. Plastic is an important material to humans but its inability to decompose makes more destructive than initially anticipated. Once plastic has been manufactured, it cannot be destroyed but it can be recycled, transformed into another plastic product, or dumped into landfills and oceans. Even when they are dumped in landfills, plastics are swept into rivers and streams, and find their way into the oceans. Plastic does more harm to the ocean than on land because marine animals do not have the ability to differentiate between plastic and prey. There are about five trillion plastic pieces floating in the earth's oceans.
Which Ocean is the Cleanest?
The South Pacific and South Atlantic Oceans are the least polluted with 297 billion and 491 billion plastic pieces respectively. Both oceans have gyres but limited human activities makes them cleaner than the rest. Both oceans are also located in the Southern Hemisphere which is less inhabited than the Northern Hemisphere. The oceans are less traversed by ships and have less inhabited islands compared to the oceans in the Northern Hemisphere.
The North Atlantic Ocean holds about 930 billion pieces of plastic. The North Atlantic Gyre led to the formation of the North Atlantic garbage patch which accounts for a large number of the plastics. The ocean lies between the East Coast of the United States, Western Europe, Northeast South America, and West Africa. These regions are known to contribute significantly to the pollution of the ocean.
The Indian Ocean was thought to be the only ocean without a garbage patch until the India Ocean Patch was discovered in 2010. The Ganges and the Indus rivers account for a large percentage of the pollutants in the Indian Ocean. The two rivers are among of the ten rivers that account for 90% of the pollution in the oceans.
The most polluted ocean is the North Pacific. It holds about two trillion pieces representing a third of the total plastics in the ocean. It is also home to the Great Pacific Garbage Patch which is the largest floating garbage patch in the world. The North Pacific is located between Asia and the West Coast of the US. It is a major shipping route between Asia and North America, and a lot of waste is dumped by ocean vessels.
Causes of Ocean Pollution
Although plastics are the major pollutants of the oceans, there are other causes of ocean pollution. Oil and chemical tankers, and offshore drilling of oil and minerals pollute the oceans. Sunken ships carrying cargo also pollute the oceans. Pollutants are dumped along the coastline but they can be found thousands of miles in the oceans because of ocean gyres.