By Noelia Almanzar, Alliance Intern from Rutgers University ‘26
With sea level rise, ecosystem destruction and climate changing more than ever, our efforts to reduce greenhouse gasses must intensify. Carbon dioxide, a major contributor of global warming, has been the focus of reduction strategies through policy but, what if the key to combating climate change has been hidden beneath the waves this whole time? “Blue carbon” is gaining traction as one of the most effective ways to decrease atmospheric CO2 — we just need to invest in the restoration and preservation of vital coastal ecosystems.
NOAA defines blue carbon as the carbon dioxide that is absorbed from the air and stored in the ocean. “Blue” relates to the water aspect of this storage. The majority of carbon is dissolved directly into the ocean, but intricate ecosystems such as wetlands and salt marshes have the potential to sequester large amounts of carbon and act as carbon sinks or places that naturally absorb CO2. Current studies suggest that coastal ecosystems sequester 10x more carbon annually than mature tropical forests, according to the National Ocean Service.
The Power of Blue Carbon to Fight Climate Change
Blue carbon is emerging as a powerful tool in the fight against climate change. But what makes it so important? Blue carbon has the potential to reduce greenhouse gasses in the atmosphere through coastal ecosystems. Coastal wetlands can store nearly 3 billion tons of carbon dioxide in the continental US, says estuaries.org. That’s equivalent to 6 million gas powered cars and 30 million acres of US forest in a year, according to EPA Equivalencies.
Now that the carbon-sequestering potential of blue carbon ecosystems is finally being recognized, scientists worldwide are exploring ways to restore coastal habitats and combat climate change. With the power to slow global warming, coastal restoration projects also have the potential for wetland-rich countries to meet their national climate goals, according to forestnews. Nations, as well as communities, can harness these natural solutions to create a more sustainable future.
The Science Behind Blue Carbon
But how does blue carbon work? To fully grasp this concept, we must understand the carbon cycle and how carbon dioxide moves through the atmosphere. In basic terms, CO2 is released into the atmosphere through breathing by people, animals and plants, as well as the burning of fossil fuels by factories, power plants and cars. Aquatic and terrestrial plants and trees then absorb CO2 during photosynthesis, converting it into oxygen and biomass. Ideally, this creates a balanced exchange between the release and absorption of CO2.
Trees sequester significant amounts of carbon within their trunks as they grow, so you hear the phrase “Plant the Trees!” to combat global warming. However, if trees are burned or removed and left to decompose in large quantities, they can become huge sources of CO2 emissions. In the same way, ecosystem destruction and other human activities expedite the release of greenhouse gases in ways that throw off the net zero balance.
Extreme environmental events, such as volcanism and increasingly frequent wildfires, also contribute to the rise in atmospheric CO2 levels. Despite these challenges, many natural carbon sinks can help mitigate this effect. These include forests and grasslands and importantly, coastal ecosystems like wetlands, mangroves and estuarine forests.
Coastal ecosystems play a crucial role in carbon sequestration, but they do so differently from forests. In these ecosystems, carbon is sequestered in both the plants and the soil, rather than in large woody trees. This is where blue carbon comes in, as it is highly effective in providing significant carbon storage. However, due to climate-caused rise of sea levels and devastating tropical storms, plus wetland dredging, carbon dioxide is being expelled from the microbially rich soils at a rate that significantly reduces their natural carbon storage capacity.
The Social and Economic Benefits of Coastal Restoration
There is no question for scientists that coastal ecosystems “represent one of the highest values of carbon stocks,” according to ScienceDirect. Coastal ecosystems, like mangroves, hold a significant amount of carbon, making them incredibly valuable.
Restoring these areas can be financially rewarding through carbon-trading programs that establish a price for carbon, which is supposed to be based on all of the environmental and social costs from global warming carbon. Having to pay for the carbon they emit creates a financial incentive for companies to reduce their emissions while providing important funding to projects that remove carbon from the atmosphere, such as coastal restoration.
Scientists measure how much carbon these ecosystems capture, including what’s stored in plants and soil. They then assign a monetary value to this carbon, creating what are known as carbon offsets.
An analysis of three US federally-funded projects reveals that investing in well-designed coastal restoration can be highly cost-effective and return significantly more than the cost of the restoration project. Each dollar invested by taxpayers returns more than $15 in net economic benefits.
The National Oceanic and Atmospheric Administration found that $1 million invested in coastal restoration creates 17.1 jobs on average compared to only 5.2 jobs from industrial coastal activities, such as oil and gas development.
My Experience with Blue Carbon Ecosystems
In my home state of New Jersey, our iconic shores are no stranger to increasingly extreme weather events and sea level rise. In Long Beach Island (LBI), a large portion of the estuarine marsh is disappearing at alarming rates. The Bay Island Restoration Project aims to restore the shoreline off the coast of LBI, as well as a group of bay islands aptly named Clam Cove to protect and increase community resilience.
I had the pleasure to see the Clam Cove coastal restoration project up close. Alongside other volunteers and the wonderful Angela Andersen, Field Station Manager for the LBI Marine Field Station, I helped bag oyster shells to place at the base of an eroded island that had once been part of a connected marsh. The oyster shells, sourced from various nearby restaurants, are being used to minimize marshland loss and enhance carbon sequestration. The shells also act as a natural oyster reef breakwater that protects the community.
Much easier than it looks, one can shovel the oyster shells into the hollow, blue cylinders that help funnel the shells into a net. Then, when it’s almost full, you can slip the cylinder out the top, leaving the net full of oyster shells at the bottom. To my surprise, the shells were much heavier than I thought but, with some elbow grease, I made it work.
What’s even better about this opportunity is that others can do this, too — that means YOU! There are many ways people can get involved with coastal restoration, from bagging shells to creating habitats for local turtles as they nest. Anyone can make a difference in their community.
Learning more about restoration projects made coastal rehabilitation feel much more attainable. I felt like I was really making a difference! The oyster shells will play a crucial role in stabilizing and restoring the coastal wetlands in the Barnegat Bay watershed.
Blue Carbon as a Tangible Solution for Climate Change
Blue carbon is not just a scientific concept — it’s a tangible solution that showcases the power of natural ecosystems. By preserving and restoring coastal habitats rich in blue carbon, we can effectively sequester CO2 from the atmosphere. From my own experience, I see that protecting coastal ecosystems helps increase biodiversity and protect coastal communities from the impacts of climate change.