Welcome to Oceans 21, a series focused on the sustainability of our oceans.

Five ocean profiles deep-dive into ancient trade networks across the Indian Ocean, the scourge of plastic pollution in the Pacific, light and life in the Arctic, Atlantic fisheries and the Southern Ocean's impact on the global climate.
We have one global ocean

Global warming, climate change, ocean acidification and overfishing are all having a major impact on the health and wealth of our oceans. And it is all connected. We are learning more every day about the complexity of the systems that drive life below the water. New research is revealing the extent of this damage, but also offering new ideas and solutions.

The world's ocean takes up more than 90% of the excess heat from burning fossil fuels and a third of the additional CO₂.

It produces most of our oxygen, helps shape the winds that influence our weather, and provides food and income for millions. The Arctic is warming faster than any other place on Earth, causing dramatic change in the coldest ocean.

Find out more about how we influence life in the ocean and what we must do to ensure its survival by exploring the articles below.

Arctic Ocean: climate change is flooding the remote north with light – and new species

"The effects of global warming are being felt around the world, but nowhere on Earth are they as dramatic as they are in the Arctic. The Arctic is warming two to three times faster than any other place on Earth, ushering in far-reaching changes to the Arctic Ocean, its ecosystems and the 4 million people who live in the Arctic."

Read more.
The Atlantic: the driving force behind ocean circulation and our taste for cod

"Much about the Atlantic remains to be discovered, especially in a changing climate ... What we do know is that the Atlantic's winds, currents and sea life are intricately connected, and disrupting them can have far-reaching effects."

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Exploring the Indian Ocean as a rich archive of history – above and below the water line

"The Indian Ocean is warming faster than any of the other oceans, holding more than 70% of all the heat absorbed by the upper ocean since 2003. Indian Ocean islands -- the Maldives being a well-known example -- are already being submerged by rising global sea levels."

Read more.
It might be the world’s biggest ocean, but the mighty Pacific is in peril

"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."

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An ocean like no other: the Southern Ocean's ecological richness and significance for global climate

"The Southern Ocean, south of 30°S, is estimated to store about 75% of the global oceanic uptake of excess heat and about 35% of the global uptake of excess carbon from the atmosphere. It is the primary storage of heat and carbon for the planet."

Read more.

All images © Shutterstock.

Hannah Hoag
Jack Marley
Nicole Hasham
Fidelis Satriastanti
Jennifer Weeks
Jennifer Gallé
Nontobeko Mtshali
Veronika Meduna
Jo Adetunji
Lucía Caballero

From The Conversation international team.