Plastic in our oceans: Scientifically recognised in the 1960s

This 2014 photo shows a black footed albatross chick with plastics in its stomach on Midway Atoll in the northwestern Hawaiian Islands.

The problem of ocean plastic was scientifically recognised in the 1960s after two scientists saw albatross carcasses littering the beaches of the northwest Hawaiian Islands in the northern Pacific.

Almost three in four albatross chicks, who died before they could fledge, had plastic in their stomachs.

Now, plastic debris is found in all major marine habitats around the world, in sizes ranging from nanometres to metres.

A small portion of this accumulates into giant floating "garbage patches", and the Pacific Ocean is famously home to the largest of them all.

Most plastic debris from land is transported into the ocean through rivers.

Just 20 rivers contribute two-thirds of the global plastic input into the sea, and 10 of these discharge into the northern Pacific Ocean.

Each year, for example, the Yangtze River in China – which flows through Shanghai – sends about 1.5 million metric tonnes of debris into the Pacific's Yellow Sea.

The Pacific Ocean is the deepest, largest ocean on Earth, covering about a third of the globe's surface.

An ocean that vast may seem invincible.

Yet across its reach – from Antarctica in the south to the Arctic in the north, and from Asia to Australia to the Americas – the Pacific Ocean's delicate ecology is under threat.

In most cases, human activity is to blame.

We have systematically pillaged the Pacific of fish.

We have used it as a rubbish tip – garbage has been found even in the deepest point on Earth, in the Mariana Trench 11,000 metres below sea level.

And as we pump carbon dioxide into the atmosphere, the Pacific, like other oceans, is becoming more acidic.

It means fish are losing their sense of sight and smell, and sea organisms are struggling to build their shells.

Oceans produce most of the oxygen we breathe.

They regulate the weather, provide food, and give an income to millions of people.

They are places of fun and recreation, solace and spiritual connection.

So, healthy, vibrant oceans benefit us all. And by better understanding the threats to the precious Pacific, we can start the long road to protecting it.

- Reprinted under Creative Commons licence.
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