The Wrack

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What is "Blue Carbon"?

Posted by | December 4, 2014 | Filed under: Opinion

It sounds cool: Blue carbon. Have you heard of it? What does it make you think?

This is an Apple mouse with a carbon fiber wrap in blue. Ah, blue carbon."I have no idea."


"Blue makes me think sky. Something to do with clear skies?"

"Sounds like a gun thing. Makes me think of guns."

"Is it a greenhouse emission?"

Okay, we're all over the place here. No doubt we need a clearer definition. Let's ask a Wells Reserve staffer.

"It's salt marshes sequestering carbon."

Yes! Annie FTW!

What is Blue Carbon?

The kind of blue carbon we have in mind has been defined in many ways — as a process, as a product, as an ability, as an ecosystem service, as a climate change mitigation benefit — but regardless of the definer's angle, they are all talking about oceans and coasts. And lately, more often than not, they're talking about salt marshes, seagrass meadows, and mangrove forests.

I'll run through a series of definitions below, but this relatively simple one from The Blue Carbon Initiative is a reasonable place to start:

Blue carbon is carbon in coastal ecosystems such as mangrove forests, seagrass meadows, and salt marshes. These ecosystems create vast carbon reservoirs by sequestering atmospheric CO2 through plant growth, then storing carbon in soil.

Straightforward and digestible, that. But the world of blue carbon science and policy expands broadly beyond the quick bite. That's one reason we're co-hosting a workshop here tomorrow, inviting experts from around the region to coordinate efforts and plan a menu of activities that will let us all be effective researchers, planners, policymakers, and advocates for the growing blue carbon movement.

Who is Involved with Blue Carbon?

Far from comprehensive and subject to change, this list will set you on a path to understanding where your interests in blue carbon might best be explored. When you're done scanning this list, I recommend "For Peat's Sake" for your next snack, followed by a sprinkling of #bluecarbon.

Restore America's Estuaries

Restore America's Estuaries (RAE) is a national nonprofit established in 1995 as an alliance of eleven community-based conservation organizations. Its mission is to preserve the nation's network of estuaries by protecting and restoring the lands and waters essential to the richness and diversity of coastal life. RAE is leading the U.S. effort to advance blue carbon, which it defines this way:

Blue carbon is the ability of tidal wetlands and seagrass habitats to sequester and store carbon dioxide and other greenhouse gases from the atmosphere, helping to mitigate the effects of climate change.

The RAE website has a section dedicated to blue carbon, with these sections (and more!):

In the first study of its kind, RAE and its partners produced a report that determined the climate mitigation benefits of estuary restoration: Coastal Blue Carbon Opportunity Assessment for the Snohomish Estuary: The Climate Benefits of Estuary Restoration.

Waquoit Bay National Estuarine Research Reserve

A project led by the Waquoit Bay Reserve received a $1.3 million grant to generate science and management tools with the potential to bring coastal wetlands into international carbon markets and incentivize investment in tidal wetland restoration and preservation. The 3-year "Bringing Wetlands to Market" project (2012-2014) examined the relationship between salt marshes, climate change, and nitrogen pollution. Some key products of the project include:

NOAA Habitat Conservation

NOAA is raising awareness about the value of mangroves, salt marshes, and seagrasses in carbon sequestration and storage to encourage conservation of these valuable habitats.

NOAA National Ocean Service

The NOAA Ocean Media Center produces the podcast "Making Waves," which focused on coastal blue carbon during one episode: "A NOAA environmental scientist explains how certain small coastal areas play an outsized role in reducing climate change."

Blue Carbon Initiative

The Blue Carbon Initiative is a global program working to mitigate climate change through the restoration and sustainable use of coastal and marine ecosystems. It brings together governments, research institutions, non-governmental organizations, and communities from around the world. The Initiative is coordinated by Conservation International, the International Union for Conservation of Nature, and the Intergovernmental Oceanographic Commission of the United Nations Educational, Scientific, and Cultural Organization.

From the Blue Carbon Initiative:

Blue carbon is a term that recognizes the role of coastal wetlands in the global carbon cycle. Tidal marshes, tidal forested wetlands, and seagrasses sequester carbon dioxide from the atmosphere continuously over thousands of years, building stocks of carbon in organic-rich soils. When coastal wetlands are drained and converted to terrestrial land uses, carbon is rapidly released back to the atmosphere in the form of carbon dioxide. Restoring coastal wetlands stops the drainage-induced releases of carbon and reactivates carbon sequestration.
In November 2012 the Verified Carbon Standard recognized Wetland Restoration and Conservation as an eligible project activity for carbon finance. In December 2013 the first global Methodology for Tidal Wetlands and Seagrass Restoration was submitted to the Verified Carbon Standard for review. Once approved, there will be mechanisms for coastal wetlands restoration projects in the U.S. and internationally to apply for carbon financing.

UNESCO Blue Carbon Scientific Working Group

The "Blue Carbon" International Scientific Working Group of the Intergovernmental Oceanographic Commission (IOC) of the UN Educational, Scientific, and Cultural Organization (UNESCO) met from 15-17 February 2011, at UNESCO headquarters in Paris, France, to discuss the implications of using coastal "blue" carbon as a conservation and management tool contributing to climate change mitigation and the development of associated conservation financing mechanisms.

These presentation slides are available to download from the working group website:

  • Coastal “Blue” Carbon Working Group Meeting
  • Global Carbon Cycle Overview
  • Mangroves
  • Carbon Sequestration & Storage in Salt Marshes
  • Seagrass Meadows as Natural Carbon Sinks
  • Methodologies for Carbon Accounting in Project Activities
  • Blue Forests: Developing Carbon Accounting Methodologies and Ecosystem Services Valuation GEF Project Development

Blue Carbon Portal

The Blue Carbon Portal was crea­ted to pro­vi­de a central on­line com­mu­ni­ty re­sour­ce and pro­fes­sio­nal net­wor­king tool to in­crea­se ac­cess to in­for­ma­ti­on and trans­pa­ren­cy in this emer­ging concept. It was developed for the international blue carbon community and is co-managed by GRID-Arendal, UNEP, and other partners.

Yale Environment 360

In his report "Why Restoring Wetlands Is More Critical Than Ever," Bruce Stutz writes:

Sea grass beds, salt marshes, and mangroves sequester and store far more carbon than equal areas of tropical forest. And because most of this 'blue carbon' is stored in submerged soil, it is released far more slowly than carbon stored in forest vegetation.… The wetland’s store of sequestered carbon will be secured for thousands of years to come.

NSF Science 360

In this NSF video, "Plum Island Estuary: Studying how marshes respond to sea-level rise," biogeochemist Anne Giblin says, "There's a lot of interest now in trying to get a quantitative handle on how much carbon is being stored in coastal areas such as salt marshes and sea grass beds. It's called blue carbon."

The Blue Carbon Project

The Blue Carbon Fund is an organization for offsetting carbon emissions through the conservation and restoration of coastal vegetation in developing countries. The problem as stated on the Blue Carbon Project website is:

The growing emission of carbon dioxide from a wide range of human activities is causing unprecedented changes to the land and sea. Identifying effective, efficient and politically acceptable approaches to reduce the atmospheric concentration of CO2 is one of society’s most pressing goals.

The solution is said to be conserving mangroves, seagrasses, and salt marsh grasses, because carbon offsets based on the protection and restoration of coastal vegetation could be far more cost effective than current approaches focused on trees.

Additional Resources

Of course, there's always more to learn…

Recognition of the C sequestration value of vegetated coastal ecosystems provides a strong argument for their protection and restoration; however, it is necessary to improve scientific understanding of the underlying mechanisms that control C sequestration.

From "A blueprint for blue carbon: toward an improved understanding of the role of vegetated coastal habitats in sequestering CO2," by Elizabeth Mcleod and 8 others, published in Frontiers in Ecology in 2011.


Victor Rivera-Monroy of Louisiana State University says “Wetlands are like a black box: We know that carbon goes in, but we don’t know what goes on once it’s in the soil.” Read more on Global Green.

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