Imagine a tree that thrives where the land meets the sea, capable of surviving in brackish water and a variety of tidal conditions, uniquely adapted to excrete salt and produce seeds that germinate while still attached to its parent. This tree’s intricate lattice root system provides shelter for fish and other species and reduces the impact storms have on coastal communities. With waxy leaves that minimize water loss in hot, saline environments and special aerial roots, called pneumatophores, that extend out of the mud to allow oxygen flow, it is well-equipped to survive in harsh conditions.
Meet the mangrove, which grows in intertidal zones in the tropics, and which governments have a prime chance to protect and restore under their revised commitments, due this year, to the Paris Agreement—the landmark 2015 United Nations climate deal.
Every five years, parties to the Paris Agreement must revise their climate action plans—also known as nationally determined contributions, or NDCs—and increase their ambitions in meeting the global climate goals.
NDCs can include commitments to cut greenhouse gas emissions, actions that avoid emissions—such as protecting ecosystems that sequester and store carbon—and pledges to enhance a country’s ability to adapt to the effects of climate change. Mangroves can assist with each of these elements, and fortunately, governments have several avenues for including them in their NDCs.
The 70-plus species of mangroves, all of which thrive in specific salinity and tidal conditions, provide nurseries for thousands of fish species—including economically important ones—and play an important role in supporting food security and coastal economies. These forests also serve as nesting areas for coastal birds and habitat for a huge variety of other life.
By capturing and storing large amounts of carbon in both their biomass and coastal sediments, mangroves, if left undisturbed, can lock away the climate-warming greenhouse gas for millions of years. In fact, mangrove forests are one of the three marine ecosystems, along with seagrass meadows and tidal marshes, with globally agreed methods from the Intergovernmental Panel on Climate Change to measure the carbon sequestered and stored within their biomass and soils.
Further, healthy mangroves buffer coastlines in the face of storms, reducing flooding, wave energy, and associated property damage. Mangroves provide flood protection for over 15 million people globally per year, which highlights how critical mangrove conservation is for climate adaptation.
Yet, mangroves are some of the most threatened ecosystems on the planet. According to a 2024 analysis by the International Union for Conservation of Nature, more than half of the world’s mangrove ecosystems are at risk of collapse because of deforestation, development, and pollution. In addition, climate change-induced storms and sea-level rise threaten a third of all mangrove ecosystems.
When mangroves are degraded or lost, the benefits they provide diminish and the carbon they’ve stored for years is released back into the atmosphere. Mangrove destruction accounts for 10% of all global emissions linked to deforestation, even though mangroves cover only 0.7% of the world's tropical forest area. Coastal communities that lose their mangroves are at higher risk of flooding, erosion, and associated property losses, as well as reduced fisheries production and food security. Governments must act to protect and restore mangroves to maintain the services they provide to people, nature, and the climate.
The Mangrove Breakthrough—a global call to action to protect and restore mangroves and to finance that action—urges governments and nonstate actors to reverse the decline of these vital ecosystems. Revised NDCs are due to the U.N. in September, and to help countries include mangroves in those plans, the Mangrove Breakthrough NDC Task Force, co-led by The Pew Charitable Trusts, has developed four new policy briefs that provide concise and practical guidance:
Pew’s advancing coastal wetland conservation project has a history of working with governments and in-country partners to support the inclusion of mangroves and other coastal wetland ecosystems in NDCs. For example, in Costa Rica’s 2020 NDC, the country committed to protecting and conserving 100% of its coastal wetlands, including mangroves, in its National Wetlands Inventory by 2025. And in 2021, Belize committed to doubling its existing mangrove area protections by safeguarding 12,000 additional hectares (about 29,600 acres) by 2030.
Governments can learn from these and other examples—and from the new task force guidance—to inform their own mangrove NDC commitments.
Launched this week, the new resources are part of the Mangrove Breakthrough NDC Task Force’s initiative to provide technical policy, data, and knowledge-sharing guidance to help transform ambition into action for the 37 governments that have endorsed the Mangrove Breakthrough to date.
Anelise Zimmer works on The Pew Charitable Trusts’ advancing coastal wetlands conservation project.