Coral reefs could be protecting hundreds of millions of people from the impact of rising sea levels and dangerous waves.
The researchers looked at 27 past studies on how coral reefs dissipate wave energy, a Stanford University news release reported.
The research team determined coral reefs reduce wave energy by about 97 percent. The reefs dissipated "disproportionally more wave energy" as the wave energy increased.
"It's obvious to the eye that waves inside a protected lagoon are much mellower than those crashing on the outer reef crest, but the extent and generality of the energy dissipation revealed by the data analysis for different locations and reef settings was surprising," study co-author Fiorenza Micheli, a professor of biological sciences at Stanford and Stanford's Hopkins Marine Station and affiliate of the Stanford Woods Institute for the Environment, said in the news release. "It is a huge reduction. The majority of wave energy is lost on the reef crest."
Human activities have taken a toll on the crucial coral reefs; at least two-thirds of the world's reefs are threatened or have already been damaged.
Between 100 million and 200 million people live 10 meters above sea level and within 50 kilometers of coral reefs. The United States has the seventh highest concentration of people living in this situation, there are estimated to be about seven million people at risk across " Florida, Hawaii, and other coastal and island areas," the news release reported.
Reducing local impacts such as pollution and coastal development or providing habitat restoration could prove to be cheaper and more effective than taking actions such as building seawalls to protect people living on the coasts.
"Reef restoration can also provide additional benefits," Micheli said. "While reducing risk, coral reefs also support biodiversity, improve water quality, and support fisheries and tourism."
