Great Pacific Garbage Patch

The Great Pacific Garbage Patch is often portrayed as a giant floating landmass in the middle of the ocean. But a better analogy would be to say the Great Pacific Garbage Patch is like a huge soup of microplastic pieces swirling throughout the ocean gyre. Or if you compare it to air pollution, it is like a plastic smog of tiny plastic particles.

The North Pacific garbage patch was discovered by Captain Charles Moore in 1997. After sailing through the area he noticed increasing amounts of floating plastic. He founded the Algalita Research Institute and returned with a research vessel over subsequent years to study and raise international awareness of the ‘Garbage Patch’.  His boat is outfitted with various trawling devices that sampled the sea surface waters, at varying depths, to collect and analyse the often invisible microplastics that permeate the water alongside the obvious larger pieces.


Plastic Free Seas was actually conceived in the Great Pacific Garbage Patch!

The founder – Tracey Read was on a plastic pollution research expedition lead by 5 Gyres and Algalita in 2012 sailing from Japan to Hawaii when she decided to start the charity on her return to Hong Kong!

Read more about Tracey’s travels through the Great Pacific Garbage Patch from the Journey to the Plastic Ocean blog.

What is a Gyre?

A gyre is a natural oceanic phenomenon of slow moving circular currents. Currents are driven by wind, tides, water temperature and salinity.

There are 5 main gyres located in the ocean: the North and South Pacific Gyres, the North and South Atlantic Gyres, and the Indian Ocean Gyre. The Great Pacific Garbage Patch is located in the North Pacific Ocean between Japan and the USA.

Garbage Patches and Gyres

Garbage patches are formed as non-natural debris from the land, fishing gear and any other rubbish floating in the ocean is ‘grabbed’ by these slow moving circular currents. The rubbish accumulates inside these gyres, and the rubbish load is denser in the centre of the patch than it is in the outer edges. The Great Pacific Garbage Patch in the North Pacific Gyre is the most well-known, although it is really made up of two gyres, the eastern and the western patches.

Why are there no photos of these giant floating landfills?

Microplastics, pieces of plastic 5mm or less, make up the majority of the plastic in the gyres which is why there are no photographs from planes or satellites of these giant floating garbage patches. As a result of the combination of sunlight which causes photodegradation, making the plastic brittle, and wave action, the larger plastic breaks into smaller microplastics.

This is the Great Pacific Garbage Patch!

Despite the fact that you don’t see any rubbish in this picture from the middle of the Great Pacific Garbage Patch, there are millions of plastic objects, nets and microplastic pieces floating throughout the ocean systems. It is not feasible to remove every piece of plastic from the ocean. To remove microplastics on a large scale will result in harm to the essential workers of the ocean – phyto and zooplankton. 

The focus should be on stopping the flow of plastics into the ocean at source. Prevention strategies are needed to reduce land and sea dumping as well as strict management of the plastics that are in use.

How do you sample plastic in the ocean?

Fine mesh nets (335micron) are dragged alongside vessels for predetermined lengths of times. Samples are collected and sorted by scientists to determine quantity, size, shape and type of plastic, and the marine life collected may also be quantifed.

How much plastic is in the Great Pacific Garbage Patch?

According to research undertaken by The Ocean Cleanup in 2018, microplastics make up 94% of the estimated 1.8 trillion pieces of plastic in the Great Pacific Garbage Patch. But that only amounts to 8% of the total weight. Of the 79,000 metric tons of plastic floating in the patch, 46% of the weight comes from abandoned fishing gear and 20% is debris that came from the Japanese tsunami in 2011.

The items featured below were found in the Great Pacific Garbage Patch during another research trip – the 2012 Tsunami Debris Research Expedition.

Small piece of a foamed cup with Japanese writing on it.

Tatami mat presumed tsunami debris.

Hair comb with nylon string and fish eggs.

Balloon remnant with plastic attachment.

Small piece of a foamed cup with Japanese writing on it.

Plastic toothbrush still in perfectly usable condition.

Foam fishing buoy with fishing line entangled.

An old glass fishing buoy wrapped with hemp rope.

Did You Know?

Lanternfish live deep in the depths of the oceans and every night they swim to the surface waters to feed on plankton. This gives them the honour of having the planet’s biggest daily migration!

Did You Know?

Laysan Albatross mate and nest on Midway Island. The adult birds can fly 1000 kilometres a month to feed from the surface of the Pacific Ocean. Much of the food they bring back to regurgitate for their chicks is plastic.

Did You Know?

In 2012, 5 Gyres worked with scientists to establish the world’s first Global Estimate of Marine Plastic Pollution. They determined that there were 269,000 metric tons and 5.25 trillion particles on the ocean’s surface.

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