Coastal challengesVital Natural buffers against Climate Change Are Just Offshore
About 31 million people worldwide live in coastal regions that are “highly vulnerable” to future tropical storms and sea-level rise driven by climate change. But in some of those regions, powerful defenses are located just offshore. Of those 31 million people, about 8.5 million directly benefit from the severe weather-protection of mangroves and coral reefs, key buffers that could help cushion the blow against future tropical storms and rising waters.
A new study finds that about 31 million people worldwide live in coastal regions that are “highly vulnerable” to future tropical storms and sea-level rise driven by climate change. But in some of those regions, powerful defenses are located just offshore.
Of those 31 million people, about 8.5 million directly benefit from the severe weather-protection of mangroves and coral reefs, key buffers that could help cushion the blow against future tropical storms and rising waters, according to the study published May 29 in the peer-reviewed journal PLOS ONE.
Because the two “natural infrastructures” absorb wave energy, reduce wave heights and provide a host of other environmental benefits, the study findings underscore the need for worldwide conservation and restoration of these natural resources. A particular focus, the authors said, should be placed on the most vulnerable regions, which lack available resources for more expensive protective measures, such as construction of levees or sea walls.
“Simply put, it’s much cheaper to conserve a mangrove than to build a sea wall,” said Northern Illinois University scientist Holly Jones, the study’s lead author.
NIU notes that a100-meter-wide coastal strip of mangroves can reduce wave heights by as much as two-thirds, previous research has shown. Coral reefs meanwhile buffer wave energy by up to 97 percent in some contexts, significantly reducing erosion and cutting flood-damage costs in half annually.
“Coral reefs and mangroves serve as cost-efficient buffers against the adverse impacts of climate change, and they already play important roles in protecting human lives and livelihoods, while providing a multitude of biodiversity benefits,” said Jones, who holds a joint appointment at NIU in biological sciences and environmental studies.
Her co-authors on the research are Barry Nickel and Erika Zavaleta of the University of California, Santa Cruz; Tanja Srebotnjak of Harvey Mudd College in Claremont, California; and Will Turner, Mariano Gonzalez-Roglich and David G. Hole of Conservation International in Arlington, Virginia.
The “Most Vulnerable”
The study aimed to identify highly vulnerable coastal regions that would benefit most from “ecosystem-based adaptation,” or using conservation, restoration and sustainable management of existing ecosystems to address climate impacts.
