Coastal blue carbon refers to the greenhouse gasses sequestered, stored, and emitted by coastal wetlands, such as salt marshes, mangrove forests, and seagrass beds, helping to mitigate the effects of climate change.

More simply, coastal blue carbon is a tool for defense against climate change that can only come from estuary and coastal habitats.

In fact, tidal wetland ecosystems can capture and store atmospheric carbon at 10x the rate of a mature tropical forest, per NOAA.

Coastal wetlands store nearly 3 billion tons of carbon dioxide in the continental United States.

Blue carbon ecosystems also play a myriad of other roles for estuaries and bays. They’re important habitats for birds, fish, and crustaceans. They also provide defense against storms, absorbing flood waters and deferring wave energy. Coastal ecosystems are an economic force for coastal communities – both in terms of the money they bring in from tourism and recreation as well as the funds they save by protecting infrastructure.

Check out blue carbon science in action in the Snohomish Estuary in Puget Sound, WA. This film was created with RAE member group,EarthCorps


According to a  2021 report from RAE, the 37,000 hectares of blue carbon ecosystems in Pamlico Sound in North Carolina store more than 10.8 million tons of carbon – the equivalent to the annual emissions of 2 million cars. Additionally, the natural infrastructure of this same area is valued to range between $48.8 and $109.9 million in damages over a 100-year period.

Unfortunately, the contiguous U.S. has lost more than 53% of its coastal wetlands in the last 200 years, per the U.S. Fish and Wildlife Service. As cities creep coastward, wetlands are drained and developed to create space for growing populations, agricultural land, and other economic opportunities. Not only does this development lessen our defenses and stress fish and wildlife, but it also  emits 3.5 million tons of carbon dioxide every year, according to the U.S. Environmental Protection Agency.

The good news is that we have solutions available to us. Restoration and protection of coastal habitats restores our natural defenses and  RAE has been leading the effort on this for some time. The bad news is that we may be running out of time. According to a  recent report from the Intergovernmental Panel on Climate Change (IPCC), we may be passing the threshold where adaptation can save us from the worst effects of climate change without a reduction in emissions.

To further the protection of coastal blue carbon ecosystems, RAE has been working with lawmakers, partner organizations, and federal agencies to institute blue carbon science into new and existing policy. Legislation from 2021 such as the  Blue Carbon for Our Planet Act and the Blue Carbon Protection Act made strides to continue incorporating blue carbon into mainstream conversation at the federal level and proves bipartisan support for coastal environments. Additionally, in 2022 we drafted a National Blue Carbon Action Plan that calls for an all of government approach to include blue carbon research and implementation into the fold at every level.