Ocean As Carbon Sink

Ocean as Carbon Sink

The ocean is one of the Earth's most significant carbon sinks, playing a critical role in the global carbon cycle and climate regulation as it absorbs and stores large amounts of carbon dioxide (CO2) from the atmosphere.Oceans have been and are a vital buffer against the impacts of climate change.

WHAT IS A CARBON SINK?

Essentially any large-scale natural system that absorbs more carbon than it releases is considers a carbon sink.

This process, known as carbon sequestration, is critical in mitigating the effects of climate change by reducing the amount of CO2 in the atmosphere.

Natural carbon sinks absorb roughly half of the human-produced carbon emissions which are driving the climate emergency.

ARE THERE OTHER CARBON SINKS BESIDES THE OCEAN?

Yes, other major carbon sinks include forests, soil, grasslands, and certain types of vegetation which also absorb CO2 from the atmosphere through photosynthesis and store it in their biomass and root systems. 

HOW MUCH IS THE OCEAN RESPONSIBLE FOR ABSORBING?

Up to now, oceans have absorbed between 25-30% of carbon emissions and about 90% of the excess heat and energy released from rising greenhouse gas emissions trapped in the Earth’s system. 

WHAT AIDS THE OCEAN IN ITS ABILITY TO ABSORB CARBON?

The efficiency of the ocean as a carbon sink is influenced by various factors, including temperature, salinity, and biological productivity. Climate change and human activities, such as pollution and overfishing, can disrupt these delicate processes.

What are carbon sinks? | Sustainability for all - ACCIONA

CREDIT: ACCIONA

CURRENT NEWS

The world’s biggest carbon sink may start emitting CO2 after net zero

By Alec Luhn 09/10/26
The Southern Ocean draws down more carbon than any other single region, absorbing about 10 per cent of human emissions. But if the world reaches net-zero emissions and atmospheric carbon dioxide concentrations fall, the ocean…
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Mangrove Forests Fight Climate Change—But Climate Change Is Fighting Back

By Kiley Price 06/05/26
Mangrove forests have adapted over tens of millions of years to survive in harsh flooding from salty seas, while locking away vast stores of climate-warming carbon and protecting the world’s coastlines from storm surge.
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BBC

Mangrove forests are healing after decades of human destruction

By Matt McGrath and Esme Stallard 06/05/26
The world's coastal mangrove forests, which protect millions of people from storms - and soak up vast amounts of planet-warming gases - are staging an unexpected comeback, scientists find.
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What floats and what sinks when it comes to ocean-based climate solutions?

By Christina Richardson 06/03/26
The oceans store an incredible share, nearly one quarter, of the carbon emitted by humans. Climate solutions that enhance this ability or cut emissions are now receiving growing attention, given their potential to scale to…
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EPA approves ocean carbon removal test, without mentioning climate

By Corbin Hiar 04/02/26
EPA is allowing a first-of-its-kind marine carbon dioxide project to move forward, even as the agency strips from its website mentions of how oceans can help mitigate climate change.
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First marine CDR focused Bill introduced in Congress

02/25/26
Congress is now considering the first-ever bill dedicated exclusively to marine carbon dioxide removal (mCDR). Introduced by Senators Murkowski (R-AK) and Schatz (D-HI), and Representatives Bonamici (D-OR-01) and Carter (R-GA-01), the Removing and Sequestering Carbon…
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How Safe is Ocean Fertilization?

By Peter Fiekowsky 02/09/26
If you Google “risks of ocean iron fertilization,” you’ll find hundreds of papers warning about toxic algal blooms, oxygen-depleted dead zones, and disrupted ecosystems. Reading them, you’d think scientists are planning to dump iron across…
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How Climate Engineering Would Alter the Oceans, Reshaping Marine Life

By Kelsey Roberts and Others 01/27/26
Climate change is already fueling dangerous heat waves, raising sea levels and transforming the oceans. Even if countries meet their pledges to reduce the greenhouse gas emissions that are driving climate change, global warming will…
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CNN

Scientists mapped what happens if a crucial system of ocean currents collapses. The weather impact would be extreme

By Laura Paddlson 06/11/25
The collapse of a crucial network of Atlantic Ocean currents could push parts of the world into a deep freeze, with winter temperatures plunging to around minus 55 degrees Fahrenheit in some cities, bringing “profound…
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Oceans Get Overlooked at COPs

By Todd Woody 11/21/24
As the world’s largest carbon sink, the ocean is a crucial bulwark against runaway global warming, yet marine issues usually receive scant consideration at the annual United Nations climate summit. While observers don’t expect a…
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They’ve Got a Plan to Fight Global Warming. It Could Alter the Oceans.

By Brad Plumer and Raymond Zhong 09/23/24
In a quiet patch of forest in Nova Scotia, a company is building a machine designed to help slow global warming by transforming Earth’s rivers and oceans into giant sponges that absorb carbon dioxide from…
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The vast, invisible effects of ocean warming

By David Wallace-Wells 06/26/24
The world’s longest-living vertebrate is not the friendly giant tortoise, the breathtaking blue whale or the saltwater crocodile, which can terrorize the imagination of toddlers and centenarians alike. It’s the shuddersome, floppy Greenland shark, which…
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KEY RESOURCES

Quantifying the Ocean Carbon Sink

08/26/22
A vital component of Earth’s atmosphere, carbon dioxide (CO2) is released through natural processes, like the breath of animals, and through human activities, like burning fossil fuels and deforestation. Since the middle of the 20th…

What is a carbon sink?

05/23/22
A carbon sink is anything that absorbs more carbon from the atmosphere than it releases – for example, plants, the ocean and soil. In contrast, a carbon source is anything that releases more carbon into…

Carbon sink

05/23/22
A carbon sink is anything, natural or otherwise, that accumulates and stores some carbon-containing chemical compound for an indefinite period and thereby removes carbon dioxide (CO2) from the atmosphere. Globally, the two most important carbon…

The Ocean, a carbon sink

05/23/22
A carbon sink is a natural or artificial reservoir that absorbs and stores the atmosphere’s carbon with physical and biological mechanisms. Coal, oil, natural gases, methane hydrate and limestone are all examples of carbon sinks.…

Carbon conservation and sequestration in ocean

11/06/21
Many coastal blue carbon ecosystems have been recently lost or badly degraded. There is a need to improve protection and consider restoration wherever practicable, through the design of novel and smart, cross-sectorial and multi-regulatory responses.

MORE NEWS

What is Coastal Blue Carbon?

06/25/24  
Healthy coastal habitat is not only important for seafood and recreation, it also plays an important role in reducing climate change. Salt marshes, mangroves, and seagrass beds absorb large quantities of the greenhouse gas carbon…
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BBC

Hurricanes, heatwaves and rising seas: The impacts of record ocean heat

By India Bourke   05/09/24  
Record ocean temperatures suggest the seas are warming faster than expected, and the impacts will be felt from polar ice shelves to coastal cities across the globe. The world's oceans are like a planet-sized battery:…
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What You Need to Know About Blue Carbon

11/21/23  
Blue Carbon is the term coined for carbon dioxide (CO2) stored in the world’s coastal and marine ecosystems such as mangroves, saltmarshes, and seagrasses. It’s called “Blue” Carbon because of its proximity to the ocean:…
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TCD

These giant, manta ray-shaped robots are designed to solve a major ocean problem: ‘Roomba meets Pac-Man’

By Wes Stenzel   10/28/23  
Climate tech startup Seaweed Generation has developed robots that look like manta rays that can sink seaweed to the bottom of the ocean to help absorb carbon.
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What This Year’s ‘Astonishing’ Ocean Heat Means for the Planet

By Elena Shao   08/03/23  
Brutal heat waves have baked the world this summer and they haven’t been contained to land. Earth’s oceans are the hottest they have been in modern history, by an unusually wide margin. The planet’s average…
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What is blue carbon?

07/26/23  
It plays an important role in absorbing and radiating heat to keep temperatures on Earth stable. But carbon dioxide levels have been steadily rising, due mainly to the burning of fossil fuels, trapping more heat…
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Warming Could Push the Atlantic Past a ‘Tipping Point’ This Century

By Raymond Zhong   07/25/23  
The last time there was a major slowdown in the mighty network of ocean currents that shapes the climate around the North Atlantic, it seems to have plunged Europe into a deep cold for over…
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Vanishing Corals: NASA Data Helps Track Coral Reefs

By Angela Colbert   06/22/23  
Coral reefs, nicknamed the rainforests of the sea, are colorful, majestic underwater worlds teeming with life. However, their future is in jeopardy due to climate change, water pollution, and other human activities. Let’s explore why…
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3 Tragic Consequences of Global Warming on Ocean Biodiversity

By Dr. Erlijn van Genuchten   06/06/23  
Currently, our planet is suffering from the tragic consequences of three crises at the same time: the climate change, pollution, and biodiversity crisis. Biodiversity refers to the different plants and animals living in a certain…
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Slowdown of the Motion of the Ocean

By Angela Colbert   06/05/23  
Dynamic and powerful, the ocean plays a vital role in Earth’s climate. It helps regulate Earth’s temperature, absorbs carbon dioxide (CO2) from the atmosphere, and fuels the water cycle. One of the most important functions…
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The off-the-charts rise of global sea surface temperature this spring has been eye-popping

By David Wallace-Wells   06/01/23  
There are a lot of unsettling signals coming from the world’s oceans right now. Even for those of us who watch things like temperature anomalies and extreme weather events as likely portents of the climate…
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Could removing carbon from the ocean be a climate change solution?

By Rosanna Xia   04/13/23  
The ocean, after all, has long been a silent hero when it comes to climate change. It has absorbed almost one-third of the carbon dioxide released by humans since the Industrial Revolution — and more…
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Why helping whales to flourish can help fight climate change

By Corinne Purtill   02/07/23  
The ocean is one of the planet’s great carbon sinks, absorbing nearly a third of the atmosphere’s greenhouse gas emissions. Swimming in its depths are the great whales, a population whose sheer physical mass allows…
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The hidden underwater forests that could help tackle the climate crisis

By Lucy Sherriff   01/02/23  
Kelp absorbs carbon dioxide and has high nutritional value, but it is under threat from rising temperatures, pollution and invasive speciesBubbles stream furiously behind Frank Hurd as he gently parts the curtains of giant kelp.…
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Oceans are warming faster than ever. Here’s what could come next.

By Brady Dennis   10/19/22  
The world’s oceans have been warming for generations, a trend that is accelerating and threatens to fuel more supercharged storms, devastate marine ecosystems and upend the lives and livelihoods of millions of people, according to…
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The ocean – the world’s greatest ally against climate change

06/03/22  
The ocean generates 50 percent of the oxygen we need, absorbs 25 percent of all carbon dioxide emissions and captures 90 percent of the excess heat generated by these emissions. It is not just ‘the…
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Kelp Is Weirdly Great at Sucking Carbon Out of the Sky

By Robinson Meyer   05/25/22  
Last month, somewhere off the coast of Maine, a small group of researchers and engineers released a series of tiny, floating objects into the water. The team called them “buoys,” but they looked more like…
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The Biggest Carbon Sink of All

By Mark Harris   05/19/22  
One of the brightest hopes for sequestering carbon lies in the darkest place on earth: the abyssal depths of the deep ocean. For millennia, dead plants and animals have sunk to the bottom of the…
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EOS

The Ocean Is Still Sucking Up Carbon—Maybe More Than We Think

By Nancy Averett   05/03/22  
The ocean plays a critical role in carbon sequestration. Phytoplankton, which live on the warm, light-filled surface, suck carbon dioxide out of the atmosphere for food. They also need nutrients such as phosphorus and nitrogen…
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The scientists fighting to save the ocean’s most important carbon capture system

By Lucy Sherriff   07/05/21  
Frank Hurd gently parted the curtains of giant kelp that reached upward through the cold waters of the North Pacific, looking for signs of life. Kelp forests cover a quarter of the world’s coastlines, stretching…
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Can Farming Seaweed Put the Brakes on Climate Change?

By Heather Smith   06/28/21  
Seaweed has been removing carbon dioxide from the atmosphere for at least 500 million years. Recent studies suggest that wild seaweed continues to do humanity a solid by sequestering 173 million metric tons annually. The…
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Saving the Ocean’s Invisible Forests

By Istu Septania   06/01/21  
The ocean is at the front line of mitigating the climate crisis. Making up over 70% of the Earth’s surface, the ocean plays a crucial role in controlling the global climate system through, among other…
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These tiny plants and giant animals are helping to store vast amounts of CO2 in our oceans

By Katharine Rooney   05/19/21  
Some of the tiniest life forms in the sea are playing a mighty role in protecting life on Earth. Scientists have discovered that microscopic plants called diatoms absorb 10-20 billion tonnes of carbon dioxide (CO2)…
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NPR

‘Run The Oil Industry In Reverse’: Fighting Climate Change By Farming Kelp

By Fred Bever   03/01/21  
In the race to stall or even reverse global warming, new efforts are in the works to pull carbon dioxide out of the air and put it somewhere safe. One startup in Maine has a…
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Blue Carbon and Green Kelp: Kelp forests could reduce carbon emissions

By Elisabeth Lang   10/09/20  
You’re probably familiar with carbon in all different forms, from pencils to diamonds, but have you heard of blue carbon? Blue carbon refers to carbon stored in marine ecosystems and is what many environmental managers…
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The oceans are absorbing more carbon than previously thought

By Dr Jamie Shutler and Prof Andy Watson   09/28/20  
The oceans cover over 70% of the Earth’s surface and play a crucial role in taking up CO2 from the atmosphere.  Estimates suggest that around a quarter of CO2 emissions that human activity generates each…
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Turning the Tide: Ocean-Based Solutions Could Close Emission Gap by 21%

By Ove Hoegh-Guldberg and Others   09/23/19  
The release of the IPCC Special Report on global warming of 1.5 degrees C (2.7 degrees F) last year urged us all to take rapid action on reducing greenhouse gas (GHG) emissions or face catastrophic…
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What are Phytoplankton?

By Rebecca Lindsey and Michon Scott   07/13/10  
Derived from the Greek words phyto (plant) and plankton (made to wander or drift), phytoplankton are microscopic organisms that live in watery environments, both salty and fresh.
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The Ocean’s Carbon Balance

By Holli Riebeek   07/01/08  
The idea seemed simple enough: the more carbon dioxide that people pumped into the atmosphere by burning fossil fuels, the more the oceans would absorb. The ocean would continue to soak up more and more…
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