Rising sea levels combined with storm surges will put nearly 4 million people in 544 US coastal cities at risk of floodiing over the next 30 years, according to new research.
The cities with the most people living within 3 feet of high tide -- the projected sea level rise by the year 2100 made by many scientists and computer models -- are in Florida, Louisiana and New York, The Associated Press reported.
California and New Jersey are also particularly vulnerable, researchers found, although virtually the entire American coastline is at some degree of risk, the New York Times reported.
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"Southeast Florida is definitely the highest density of population that's really on low coastal land that's really most at risk," said lead author Ben Strauss, a scientist at Climate Central, a New Jersey-based group of scientists and journalists who research climate change.
The report, titled "Surging Seas," is based on two peer-reviewed studies, both published in the journal Environmental Research Letters, that used a new method examining the risk of rising seas, CNN reported.
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According to the research, the odds of once-in-100-years flooding hitting regions of the coastal U.S. have more than doubled, CNN reported.
To lessen the possibility of catastrophic flooding, the research 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.