A recent study from the Center for Coastal Climate Resilience at UC Santa Cruz has revealed that mangroves provide $855 billion in flood protection services globally. This research, led by Pelayo Menendez and Michael W. Beck, is highlighted in the World Bank’s 2024 edition of The Changing Wealth of Nations.
The study, titled Building Coastal Resilience with Mangroves: The Contribution of Natural Flood Defenses to the Changing Wealth of Nations, emphasizes the vital function that mangroves serve in shielding coastal areas from floods, storm surges, and erosion. This protection not only benefits local populations but also supports national economies significantly. As climate change increases the intensity and frequency of storms, the demand for robust coastal defenses has never been more pressing. Traditionally, governments have relied on hard infrastructure like seawalls and levees to prevent flooding. However, the research indicates that natural ecosystems, particularly mangroves, can offer equally or even more effective coastal protections while also delivering extra environmental advantages.
Initially recognized as coastal protection assets in the 2021 edition of The Changing Wealth of Nations, this new research builds on that foundation by utilizing updated global data from 2020, which gives a clearer understanding of the enduring protective value of mangroves. The researchers, Menendez and Beck, examined mangrove forests across 121 countries, encompassing 700,000 kilometers of subtropical coastlines using sophisticated flood risk models.
The findings reveal that the worth of mangroves in reducing flood risks is soaring, primarily due to rising populations, economic growth, and increasing storm activity along coastlines around the globe. From 1996 to 2010, the estimated value of mangroves for flood-risk reduction grew by $130 billion, and from 2010 to 2020, their long-term benefits surged by an additional $502 billion. Although there has been some reduction in mangrove areas due to shrimp farming and coastal development, their value as protective barriers has increased as more communities and infrastructure depend on them.
“The evidence is unmistakable: Mangroves are essential for mitigating flood risks and must be recognized as significant natural assets,” stated Menendez. “They provide affordable protection for coastal populations and enhance national wealth by safeguarding lives, livelihoods, and infrastructure.”
This research highlights not only the environmental significance of mangroves but also their economic value as natural capital. The $855 billion reflects the anticipated worth of mangroves’ flood protection services over the next century. Countries that benefit the most from these services include China, Vietnam, Australia, the United States, and India each year.
Interestingly, although mangrove loss continued from 2010 to 2020, the pace of decline has significantly slowed to merely 0.66 percent. During this same timeframe, the protective value of mangroves increased at a rate faster than the overall flood risks. This shift indicates that in 2020, mangroves were responsible for protecting 61 percent more people and securing 109 percent more capital assets from floods compared to ten years earlier.
Countries such as Vietnam, Bangladesh, India, China, and Cameroon have gained substantially from this progress, with mangroves providing protection to hundreds of thousands of individuals annually. Conversely, nations like Malaysia, Myanmar, and Taiwan experienced a drop in mangrove benefits, signifying the urgent need for greater conservation efforts in these areas.
The timing of these findings is crucial, as countries worldwide seek sustainable solutions to mitigate rising climate risks. Mangroves present a natural, cost-efficient approach to flood protection, solidifying their place as an integral part of any climate adaptation strategy.
As policymakers plan for the future, this study argues strongly for the importance of investing in mangrove conservation and restoration. “Protecting and restoring mangroves is not just an environmental imperative; it’s an economically wise decision,” asserted Beck. “These ecosystems provide essential services that bolster resilience to the escalating challenges of climate change.”
The Center for Coastal Climate Resilience has also shared these results and data through the Coastal Resilience Explorer decision-support tool.
