10 interesting facts about the Great Pacific Garbage Patch

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Plastic Island, The Great Pacific Garbage Patch, Trash Island: whatever you call it, this massive accumulation of plastic debris located between Hawaii and California is growing bigger day-by-day.

But what is it made from? Where does it come from? And what can be done about it? For answers to these questions and more, keep reading…



1. It was discovered by oceanographer and boat captain Charles Moore

In 1997, Oceanographer and boat captain Charles Moore was sailing his boat home to California after completing the Los Angeles to Hawaii Transpac sailing race.

Charles Moore, oceanographer and discoverer of the Great Pacific Garbage Patch. Photo credit: Wikipedia

When Moore and his crew were sailing through the North Pacific Gyre, one of the most remote parts of the ocean, they observed large amounts of plastic debris floating in the ocean. Moore later wrote of his discovery:

As I gazed from the deck at the surface of what ought to have been a pristine ocean, I was confronted, as far as the eye could see, with the sight of plastic. It seemed unbelievable, but I never found a clear spot. 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.

A colleague of Moore’s dubbed the vast area of plastic debris the ‘Great Pacific Garbage Patch’, and the name has stuck ever since.

Charles Moore now works at the Algalita Marine Research and Education in California, an organisation dedicated to “giving young people the opportunity to take up the charge against plastic pollution.”

2. It is roughly three times the size of France

There’s a common misconception when it comes to the Great Pacific Garbage Patch: that it’s an actual island. This misconception probably comes from the fact that it is sometimes called ‘plastic island’. It is not an island, rather it is a huge patch of ocean that contains a high concentration of plastic debris.

The patch covers an estimated surface area of 1.6 million square kilometers. That’s twice the size of Texas, or three times the size of France. The patch cannot be seen from space, as is sometimes claimed.

Making things more complicated, the location of the patch can vary over time, depending on the time of year.

3. Fishing nets account for around 45% of the Great Pacific Garbage Patch

Almost half of the Great Pacific Garbage Patch is made up of abandoned or lost fishing nets. Credit: The Ocean Cleanup

When fishing gear becomes abandoned or lost, it becomes known as ‘ghost gear’. According to a recent study, 46% of the Great Pacific Garbage Patch is made up of fishing nets. Laurent Lebreton, the lead author of the study, explained to National Geographic:

“I knew there would be a lot of fishing gear, but 46 per cent was unexpectedly high. Initially, we thought fishing gear would be more in the 20 per cent range. That is the accepted number [for marine debris] globally—20 per cent from fishing sources and 80 per cent from land.”

One of the problems with ghost gear is that it can continue to catch marine animals long after being abandoned. When a piece of ghost gear captures an animal, it is known as a ‘ghost catch’.

Marine life that is unfortunate enough to enter the Great Pacific Garbage Patch, such as fish, sea turtles and dolphins, are at serious risk of becoming ensnared by a piece of ghost gear.

4. The Great Pacific Garbage Patch is just one of five similar patches

The Great Pacific Garbage Patch is found within the North Pacific Gyre, which is one of five major ocean gyres in the world.

The definition of an ocean gyre, as per Wikipedia, is: “any large system of circulating ocean currents, particularly those involved with large wind movements. Gyres are caused by the Coriolis effect; planetary vorticity along with horizontal and vertical friction”

The other major ocean gyres are The Indian Ocean Gyre, The North Atlantic Gyre, The South Atlantic Gyre and The South Pacific Gyre.

Although the Great Pacific Garbage Patch is the largest and most densely polluted ocean patch in the world, it is by no means the only garbage patch in the world. Every major ocean gyre has a garbage patch. For example, the North Atlantic Garbage Patch is estimated to be hundreds of miles across and contains over 200,000 pieces of plastic debris per square kilometer.

5. Once plastic enters the patch, it is unlikely to ever escape

No escape: the circular movement of ocean currents make it very difficult for plastic debris to ever escape the Great Pacific Garbage Patch

The reason why debris accumulates in these areas can be explained by looking at what an ocean gyre actually is. An ocean gyre acts as a huge circular conveyor belt. It means that once debris enters the gyre, it is very difficult for it to escape, due to the circular nature of the currents.

Ocean gyres are caused by the Coriolis Force (the rotation of the Earth) and the wind patterns. Gyres help circulate water around the globe, which is essential for regulating temperature, salinity and nutrient flow in the world’s oceans.

Ocean gyres have been circulating water around the world for millions of years. In recent years though, as well as circulating water around the globe, they have begun to act as trash vortexes, pulling in plastic debris and not allowing it to escape.

6. The Great Pacific Garbage Patch contains between 1.1 to 3.6 trillion pieces of plastic

When exposed to sunlight, plastic breaks into smaller and smaller pieces, until they are classed as microplastics.

The Great Pacific Garbage Patch contains a staggering number of pieces of plastic, estimated to be between 1.1 to 3.6 trillion. That’s roughly 200 pieces of plastic for every person on the planet.

To understand why there are so many, it’s important to understand the way in which plastic decays. It does not biodegrade in the same way that a piece of fruit would.

Rather, plastic undergoes a process called ‘photodegradation’, whereby it decays when exposed to sunlight. But rather than simply disappear, the plastic breaks into smaller and smaller pieces. This process repeats until you would need a microscope to even be able to see the plastic particles.

Once plastic particles are measured at 5 mm or under, they become classed as ‘microplastics’.

Scientists are unsure whether plastic truly ever disappears, or whether it just keeps breaking into ever smaller pieces.

What we do know is that microplastics are terrible news for marine life. Tiny particles of plastic can easily be mistaken for food, and end up being ingested by fish, sea turtles, and mammals.

7. The plastic does not just exist on the surface of the patch, but underwater as well

Plastic does not just exist on the surface of the ocean but extends all the way to the sea floor

Some types of plastic are more buoyant than others, and not all plastic floats.

Microplastics have been discovered inside the Great Pacific Garbage Patch at every level under the water level, all the way down to the ocean floor.

Scientists estimate that up to 70% of the plastic debris in the GPGP will sink to the bottom of the ocean.

A diagram showing the density of a range of plastics, and whether they will sink or float in seawater. Credit: http://www.grida.no/resources/6930

Plastic bottles tend to sink to the bottom quite quickly, whereas plastic bags will usually float on the surface of the water. Other types of plastic can be suspended, neither rising to the surface nor sinking to the sea floor.

8. Plastic will account for roughly 74% of the diet of sea turtles that enter the area

Because of the sheer volume of plastic within the Great Pacific Garbage Patch, it should come as no surprise that marine animals that venture into the area end up ingesting plastic. In fact, researchers discovered that around 74% of the diet of sea turtles within the GPGP consists of plastic debris.

A side-by-side comparison of a plastic bag and a jellyfish

Plastic bags can be particularly tempting to sea turtles, as they closely resemble a key part of the turtle’s diet: jellyfish. The picture above illustrates how similar they look when they are submerged in water.

A scientific study carried out by a team in Japan found that Loggerhead Turtles ate plastic 17% of the time they encountered it.

As well as ingesting it, sea turtles are also in danger of becoming entangled in plastic. Having their flippers wrapped in plastic can often result in death, as they lose the ability to swim and feed themselves.

9. It contains plastic that is decades old

In the grand scheme of things, plastic has only been around for a very short amount of time. It was only in the 1950s that plastic began to be mass produced.

Every piece of plastic that has ever been produced is still in existence today. A plastic toy you played with when you were a child is still out there somewhere – perhaps it now exists in a million tiny pieces, but the plastic is still plastic, and it’s not going away any time soon.

Scientists don’t even know if plastics will ever truly disappear. You’ll read estimates online of 500 years or 1000 years, but they are just that: estimates.

Photo credit: The Ocean Cleanup

This plastic crate was found in the Great Pacific Garbage Patch. It was found to have been manufactured in 1977.

It may be a little frayed and a little washed out, but it is still very much recognisable as a crate. It still looks strong.

Pieces from this crate have obviously broken off. These pieces will then break into smaller pieces, which will break into smaller pieces. And on and on this process will go, century after century.

10. The largest ocean cleanup in history is underway to try to remove plastic from the ocean

The Ocean Cleanup project aims to clean up 50% of the plastic in the GPGP within five years

The Ocean Cleanup is an initiative founded and lead by Boyan Slat. Slat became interested in the issue of plastic pollution as a 16-year-old boy scuba diving while on vacation in Greece. He was shocked by the amount of plastic he found while diving and set about working on a potential solution.

Showing incredible drive and ingenuity, in 2013 Slat founded the non-profit organisation ‘The Ocean Cleanup’.

Thanks to crowdfunding and donations from Silicon Valley entrepreneurs, The Ocean Cleanup raised over $31.5 million USD to launch the biggest ocean cleanup in history.

The Ocean Cleanup system consists of a 600-meter long floating boom, which collects plastic debris into a containment area.

Once the debris has been contained, it will then be picked up by a ship, which acts as a ‘garbage truck of the sea’.

The goal of the Ocean Cleanup is to remove 50% of the plastic within the Great Pacific Garbage Patch within five years before moving on to tackling the debris in the other ocean gyres.

The Ocean Cleanup commenced in October 2018. We’ll post more updates as they come in.

Learn more about the Ocean Cleanup on their official website.