Extreme weather, rising sea levels and degraded coastal ecosystems place people and property at greater risk from ocean waters, which is why a group at Stanford University have put together a map of the nation depicting where natural habitats most effectively reduce the risk of storms like Hurricane Sandy.
"Our analyses deliver the first national map of risk reduction owing to natural habitats and indicates where conservation and restoration of reefs and vegetation have the greatest potential to protect coastal communities." the team wrote in their study.
Called InVEST (Integrated Valuation of Ecosystem Services and Trade-offs), the group used five sea-level-rise scenarios to calculate the hazard index for every 1 kilometer squared of the U.S. coastline. Once this index was determined, the researchers then used it to identify the most vulnerable regions.
In doing so, they found that the number of variables, including low-income families, elderly as well as the total value of residential property most exposed to hazards could be reduced by as much as half should existing coastal habitats remain fully intact.
Coastal habitats includes marshes, dunes, seagrass beds, mangrove and other coastal forests, kelp forests and coral reefs - all of which help to keep storm surge from flooding and eroding the coasts themselves. For example, according to the National Geographic, coral reefs alone can help reduce the energy of waves that hit the shore by as much as 85 percent.
All told, the researchers found that approximately two-thirds of the U.S. coast is currently protected by one or more of these natural habitats, with the greatest number of people and property value benefitting from them in Florida, New York and California, according to the study.
When the team modeled the coastlines without the natural protections, the team found that the amount of stretches of coastline now highly exposed to floods and storms would double, exposing an additional 1.4 million Americans to such threats.