Featured Seawords Article

Features Seawords Article April 2018

The Great Pacific Garbage Patch

While imagining the vast expanses of the open ocean of the Pacific, hundreds of miles away from any land, it can be easy, and perhaps right, to picture it as an unsullied environment, a vast unbroken landscape of blue waves, and possibly the most pristine one can get on our human-run Earth. Unfortunately, such an assumption does not reflect reality, and even some of the most barren stretches of open sea can be the ones most affected by human activity.

Such is the case of the Great Pacific Garbage Patch, an enormous stretch of ocean that was found to be overrun by plastics and other human refuse. While scientists had predicted the existence of such a “trash vortex” for many years, it wasn’t until activist Charles Moore discovered it in 1997 during a yachting race that took him through the region. Since then, the collection of human garbage has been monitored, and many scientists are trying to figure out how to fix the problem.

This patch, nicknamed “trash island” (which is actually not accurate, as in some areas the garbage has been broken down enough to be more of a plasticy “soup”) formed thanks to currents swirling around the majority of space of the Pacific Ocean, forming an area of calmer water in the middle called a gyre. This acts a bit like an enormous, slow-moving drain, where anything caught within the currents are eventually gathered into the center, in some cases taking as long as seven years. This leaves giant collections of discarded human garbage to slowly gather and grow. While the Pacific patch is the largest of these trash vortexes, with some estimates placing it at twice the size of Texas (which, again, is hard to determine, thanks to the more “soupy” texture and indiscriminate boundaries of some parts), similar patches have been found growing in the Indian and Atlantic Oceans, as well as smaller bodies of water such as the North Sea.

The Great Pacific Garbage Patch is a little bit of a misnomer, as there are actually two main patches in the Pacific, the Eastern Patch (which is between California and Hawai'i) and the Western Patch (which is off the coast of Japan). A band of water above Hawaiʻi where warmer southern water and cooler northern water meet, called the “North Pacific Subtropical Convergence Zone,” connects the two patches with a near-constant collection of trash itself. These two main patches, and the garbage-filled bridge connecting them, collectively form the Great Pacific Garbage Patch.

While anything from tennis shoes to Legos can be found in the vortexes, 80% of the garbage is plastics. This is because A) plastic is easy to make and cheap to use, and B) is not biodegradable, meaning that microbes that can break down other trash do not recognize plastic as food, therefore leaving any plastic refuse to theoretically lay untouched forever. Plastic is photodegradable, meaning that the sun will eventually break it into smaller pieces. Unfortunately, this does not actually convert the plastic to a less problematic form, and instead just makes them small enough to be considered “microplastics,” which form the aforementioned soupy or cloudy looking waters in the patch. These microplastics can have an even worse effect on their environment than when in a large form, as the film they cause over the surface of the water stops sunlight from fully penetrating the sea, not allowing any photosynthetic organisms to grow. This disrupts the entire food web, affecting herbivorous animals, to their large predators, all the way up the trophic ladder until the human fishing industry is disrupted. Possibly worse, microplastics are now small enough to be considered food to small animals and plankton, meaning that any toxins that plastics naturally have (BPA) or absorb from their environment (pollution like PCBs) are entered in the food web as well. In short, more microplastics means less seafood will be available, food that is available will be at a higher price, and the food will be toxic to eat. All in all, a poor combination for us and animals affected.

Researchers have spent years trying to figure out a way to clean the garbage patch, and have had poor luck due to the sheer scale of the endeavor - NOAA estimates that it would take 67 ships one year to clean up less than one percent of the surface trash. However, a new solution has recently been proposed. “The Ocean Cleanup” is a Netherlands organization working to get rid of marine plastics, and have proposed an ocean cleanup system meant to collect much of the refuse at the surface of the sea, in the garbage vortex or elsewhere. Their mechanism has undergone numerous redesigns to better efficiency and has had field tests in the Netherlands. Now, the program has leased an old naval station near San Francisco and will be using this location as a home base of sorts as they try to clean the Eastern Garbage Patch. Models and test runs have been positive, and now they hope to officially launch their first attempt at cleanup in mid-2018. The apparatus, which will be nearly two kilometers when fully constructed, consists of large, strong floating “arms” that act as a buoy for large solid sheets hanging for several dozen feet underneath, which when together form a vague U-shape. The plan is for the apparatus to essentially mimic plastic behavior, floating with the same currents and conditions as the trash already in the gyre. However, as deeper water tends to move slower than surface water, large anchors will be suspended from the floaters as well, allowing the entire construct to move with plastics but at a slower rate, essentially trapping surface and sub-surface plastics in an enormous U-shaped traffic jam. The organization believes this can clean up 50 percent of the patch’s garbage within the first five years of use. This method also averts criticisms of previously-mentioned solutions - for instance, while dredging the patch with nets would catch and kill any animal caught, the Ocean Cleanup method uses solid sheets to catch plastic, so animals do not run a risk of getting tangled, and to get past can simply dive underneath. Furthermore, this is a passive instead of active solution - using up less energy, time, and money - and any electronic parts that do need energy will get this via solar panels. What’s more, any plastic caught will be recycled and reconstituted to be sold for other purposes, allowing the project to basically fund itself.

While it still remains to be seen just how successful this project will be, trials seems promising and we can only hope that this attempt ends in success. However, all researchers trying to solve this issue agree: the best way to stop the patch is to change our behavior and prevent such refuse from gathering entirely.

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