Within our oceans lie sprawling, swirling masses of plastic waste, threatening marine life and our planet’s health. There are five of these so-called “garbage patches,” each an unsettling symbol of our environmental impact. The Pacific and Atlantic Oceans contain two patches each (North and South) and there’s one in the Indian Ocean as well. The largest and most well-known, is the Great Pacific Garbage Patch. It is found in the North Pacific Subtropical Gyre, between Hawai’i and California.
What exactly are gyres?
Formed by rotating ocean currents, debris is pulled in and collects in a whirlpool-like manner, creating large garbage vortexes. The term ‘patch’ may conjure up a floating island of plastic, but these debris areas are actually spread across the ocean’s surface, and even reach down to the ocean floor.
Much of the 94% of the 1.8 trillion pieces in the Great Pacific Garbage Patch are tiny microplastic pieces smaller than 5 mm in length. Contrary to what a lot of people imagine is a mountain of trash in the water, garbage patches are more akin to a peppered soupy mixture of varying debris sizes. In the words of the founder of Greenseas Trust, Fazilette Khan, “Having sailed through it myself, you would not know it was there!”
This makes measuring the area incredibly difficult, because the pieces of garbage are moving with the changing currents and winds. A 2018 study reported that the Great Pacific Garbage Patch spans 1.6 million square-kilometres of the ocean, which is three times the size of France and between four and sixteen times larger than was previously estimated.
The Great Garbage Patch
Captain Charles Moore discovered the Great Pacific Garbage Patch in 1997. When he sampled the ocean’s surface, he found six times more plastic than plankton. So why is so much marine debris made of plastic? Because of its low cost, plastic is used in an overwhelming amount of consumer products and is all around us, even in our chewing gum! Additionally, plastic is not biodegradable; instead it photodegrades into smaller and smaller pieces, becoming the microplastics previously mentioned.
They may be small, but microplastics have big negative impacts! When they accumulate on the ocean’s surface, they prevent sunlight from getting to the autotrophic organisms which need it, such as phytoplankton and algae. Without sunlight, these nutrient producers can’t survive, which has a knock-on effect throughout the entire marine food web.
Larger pieces of debris cause marine animal to get entangled, or they mistake plastics for food, both of which can be detrimental to their survival. Moreover, marine wildlife can get transported on/with the swirling, travelling debris as an invasive species where they can disrupt local ecosystems.
Prevention is better than clean-up
Prevention is the key to remedying the garbage patch quandary. If the bath were overflowing, the first course of action would be to turn the tap off. Similarly, we can stop plastics entering our waterways and seas by reducing the amount of plastic waste we produce globally. There are also a number of small switches we can all make that can help. Amongst them are; reducing our personal single-use plastic consumption, reusing, recycling and avoiding littering. Finally, we can join a coastal or river clean-up to remove plastics before they have a chance to break down and wreak havoc in the ocean.