Facing long-term climate threats like rising seas and coastal erosion, communities in Guam and the Northern Mariana Islands are looking to their coastlines for solutions.
Not with concrete walls, but with mangrove roots and seagrass beds.
A recent regional webinar titled “Blue Carbon Ecosystems and Nature-based Solutions” brought together more than 100 participants from across the Pacific and Asia to talk about how nature-based solutions, particularly blue carbon ecosystems, could play a bigger role in national climate plans.
Blue carbon refers to the carbon stored in coastal ecosystems like mangroves, seagrasses and tidal marshes. These habitats not only absorb carbon dioxide but also protect coasts from flooding, support marine biodiversity and sustain local fisheries.
“This is the time to scale up blue carbon action,” said Juhi Bansal, a climate consultant who moderated the session. “It’s exciting to see people joining from countries where blue carbon ecosystems clearly matter.”
For Guam and the CNMI, where coastlines are already eroding and the risks of stronger typhoons loom large, the conversation hit home. These island communities are among the most vulnerable to the impacts of climate change, yet they also hold some of the most powerful tools for resilience — their natural ecosystems.
The region holds more than half the world’s mangrove forests, according to the United Nations Economic and Social Commission for Asia and the Pacific. That’s about 7.5 million hectares.
“These ecosystems provide an estimated US$1.5 trillion annually in services like storm protection and fisheries support,” said Aneta Nikolova, an environmental affairs officer with ESCAP.
But those ecosystems are shrinking. Nikolova said the region has lost 616 megatons of mangrove carbon while restoring only 314 megatons in recent years. Coral reefs and seagrass beds are also under threat.
Coastal ecosystems are part of Guam’s long-term climate resilience plans. The Guam Green Growth Initiative, led by the University of Guam’s Centre for Island Sustainability, is exploring blue economy strategies and has recently launched the GROW Corps to train residents in environmental restoration work.
The GROW Corps, made up of young adults from across the island, is working in partnership with government agencies and nonprofits to protect watersheds, replant native species and monitor marine health.
In the CNMI, local agencies and NOAA have tracked changes to coral and seagrass habitats. A 2023 survey found that while some areas are recovering, others are declining due to heat stress, pollution and development pressures. A separate study by the CNMI Bureau of Environmental and Coastal Quality recommends expanding seagrass monitoring and exploring nature-based adaptation to address climate vulnerability.
“Blue carbon ecosystems aren’t just carbon sinks,” Nikolova said. “They also support biodiversity, food security and protect our coasts.”
The webinar also introduced a four-part framework for regional ocean-based climate action: protect and restore blue carbon ecosystems, decarbonise shipping,promote ocean-based energy and build ocean resilience.
Manuel Castillo of ESCAP said the region has the political will but needs more action. He pointed to the UN Ocean Conference in France last month, where climate appeared 26 times in the final declaration. That’s a significant shift, he noted, from earlier years when marine ecosystems were often sidelined in climate discussions.
“Many marine protected areas exist only on paper,” Castillo said. “We need stronger enforcement, better data and real commitments to restoration.”
Kathryn Bimson of IUCN Asia said territories like Guam and the CNMI can align with global frameworks even if they are not UN member states. Tools like the Ramsar Convention and Global Biodiversity Framework offer ways to integrate wetlands and coastal protections into climate targets.
She also emphasised that local governments can lead by example — piloting projects, developing policy and engaging the public.
Restored mangroves alone offer over $60 billion in flood protection globally each year, according to conservation studies. These forests reduce wave heights, stabilise shorelines and create nursery grounds for fisheries.
But funding is a major hurdle. The NDC Partnership estimates that US$83 billion is needed worldwide to support coastal ecosystems, but only about a third of that has been secured. In many cases, island governments lack the capacity to apply for or manage international funding, creating an additional barrier.
To help close the gap, the NDC Partnership and Green Climate Fund released a new planning guide focused on blue carbon. It outlines how countries and jurisdictions can collect data, build policy frameworks and empower communities to manage coastal ecosystems. The guide stresses collaboration between sectors — environment, climate, finance and traditional leaders.
Deo Gabinete of the NDC Partnership said there are successful models already. Vietnam and Belize have used blue bonds to finance mangrove protection. Indonesia has included mangroves in its climate pledges and now has one of the largest mangrove restoration programs in the world.
“The knowledge already exists in communities,” Gabinete said. “The key is to bring in financial and technical support to scale those efforts.”
In the CNMI, local researchers are still mapping seagrass beds and coral reefs to better understand where to prioritize restoration. Citizen scientists and volunteers are helping track changes in seagrass near Laolao Bay and other critical habitats.
In Guam, watersheds and marine preserves, such as Piti and Sasa Bay, provide natural laboratories for understanding blue carbon in action. These ecosystems absorb carbon, protect against flooding and help marine life thrive. The Guam Coral Reef Initiative has also launched new projects to track coral bleaching and test strategies for reef recovery.
But seagrass remains largely unstudied in many parts of the Pacific. ESCAP estimates the region’s 14.9 million hectares of seagrass store around 2 gigatons of carbon. That’s equal to nearly 8 gigatons of carbon dioxide. Despite this, few countries include seagrass in their climate policies or biodiversity plans.
“We need more data on seagrass, especially in the Pacific,” Nikolova said.
