Rising sea levels combined with storm surges will put more than 5 million people on U.S. coastlines at risk of flooding during the next 30 years, according to new research.
The combination could raise sea levels during storms to 4 feet above the high-tide line, threatening property that contains 2.6 million homes on 3 million acres of land, according to the report released Wednesday by Climate Central, a nonprofit research and journalism organization based in New Jersey.
“Escalating floods from sea level rise will affect millions of people, and threaten countless billions of dollars of damage to buildings and infrastructure,” Climate Central's Ben Strauss, the lead author of the report, said in a statement.
The report, titled "Surging Seas," is based on two new peer-reviewed studies, both published in the journal Environmental Research Letters. Climate Central calls it "the first major national analysis of sea level rise in 20 years."
It says the odds of once-in-100-years flooding hitting regions of the coastal U.S. have more than doubled.
“Just a small amount of sea level rise, including what we may well see within the next 20 years, can turn yesterday’s manageable flood into tomorrow’s potential disaster," Strauss said in a statement.
The report takes flood analysis down to the local level. In 285 coastal cities and towns, half the population lives below that 4-foot mark, it says. Florida faces the biggest threat from the coastal flooding, according to the researchers.
"A preliminary independent analysis suggests about $30 billion in taxable property is vulnerable below the 3-foot line in just three counties in southeast Florida, not including the county with the most homes at risk in the state and the nation, Miami-Dade," a summary of the report says.
Other states facing substantial risk are Louisiana, New Jersey, North Carolina, Maryland, New York and Virginia, the report says. The report includes interactive maps showing how the rising seas could hit local areas.
To lessen the possibility of catastrophic flooding, the report calls for action to fight global climate change.
"The United States must work to slow sea level rise by reducing emissions of heat-trapping gases, and work to diminish the remaining danger by preparing for higher seas in coastal cities and counties everywhere," it says.