- Date: 25 September 2019
- Author: Lauren Spurrier, vice president, ocean conservation
A new UN report warns the world that as climate change heats up the oceans and ice sheets and glaciers melt, one billion people who live in low-lying coastal areas will be at risk rapid sea-level rise. But there is something we can do—spend money on saving mangroves. And it’s a smart investment.
A recent report by the Global Commission on Adaptation calculates mangroves yield $1 trillion in net benefit for climate adaptation, which would be gained by 2030 if we began investing in conservation soon.
Mangroves are natural providers for people
Mangrove trees serve as the interface between land and sea, providing a variety of benefits to both nature and people.
Mangrove forests provide more than $80 billion per year in avoided losses from coastal flooding, and they also protect 18 million people. In addition to other non-market benefits associated with fisheries, forestry, and recreation, the flood protection benefits from mangrove preservation and restoration are worth up to 10 times the costs.
Building natural resilience
Another benefit is that mangroves act as a nature-based solution for disaster risk reduction. There are a number of case studies around the globe showcasing how mangroves can attenuate storm surge, stabilize shorelines from erosion, buffer rising sea levels, and contribute to general flood control. As a model of ‘green’ infrastructure, mangroves can stand alone as a form of defense or be integrated with traditional, or ‘grey’ infrastructure, depending on local context and factors. Regardless, in many cases mangroves are essential for reducing the vulnerability of coastal communities to the impacts of climate change and increasingly intense and frequent extreme weather events.
Vulnerability to climate change
It is imperative to invest in mangrove protection now, because while these forests can help mitigate the impacts of climate change, they themselves are vulnerable to its effects.
Mangroves are directly affected by rising sea levels, increasing atmospheric carbon dioxide, warmer air and water temperatures, changing ocean currents, and the increasing variability and intensity of rainfall. How and whether mangroves survive in a future of increasing climatic change will be determined by whether they can migrate inland, where and how mangroves are situated, continued supplies of sediment, and whether migration inland can outpace the rate of sea-level rise.
The implications of the combined impacts of sea-level rise, changing salinity, extreme weather events, economic development, and infrastructure development should be understood to best determine how mangroves might contribute to risk reduction for people in long-term disaster risk reduction planning. At the same time, urgent action must be taken to reduce threats to existing mangroves and to enable mangroves to migrate inland and to new areas as sea levels rise.
Investing in bringing solutions to scale
No one community, government or organization can realize the $1 trillion return of saving mangroves on its own. This is an all-hands-on-deck moment.
WWF has helped found the Global Mangrove Alliance, which aims to increase mangrove coverage 20% by 2030. The Alliance brings together technical experts, civil society organizations, governments, local communities, businesses, funding agencies and foundations to accelerate a comprehensive, coordinated, global approach to mangrove conservation and restoration at a scale that matters.
The tide is turning on how we view our natural resources, especially in the face of a shifting climate, from a source of exploitation or removal to one of need for natural resilience. Mangrove forests could be considered the flagship habitat for this shift in thinking. It’s time to go all-in and put our collective investment in this natural climate solution.