As the Earth’s climate changes, the worst inundations from hurricanes and tropical storms could become far more common in low-lying coastal areas, a study from Princeton and the Massachusetts Institute of Technology (MIT) suggests. The study found that regions such as the New York City metropolitan area that currently experience a disastrous flood every century could instead become submerged every one or two decades.
The researchers reported in the journal Nature Climate Change in February 2012 that projected increases in sea level and storm intensity brought on by climate change would make devastating storm surges — the deadly and destructive mass of water pushed inland by large storms — more frequent. Using various global climate models, the team developed a simulation tool that can predict the severity of future flooding an area can expect.
The researchers used New York City as a test case and found that with fiercer storms and a 3-foot rise in sea level due to climate change, “100-year floods” — a depth of roughly 5.7 feet above tide level that occurs roughly once a century — could more likely occur every three to 20 years. What today are New York City’s “500-year floods” — or waters that reach more than 9 feet deep — could, with climate change, occur every 25 to 240 years, the researchers wrote.
The research is not only the first to examine the future intensity of storm surges, but also the first to offer a tool for estimating an area’s vulnerability to future flooding, said co-author Michael Oppenheimer, the Albert G. Milbank Professor of Geosciences and International Affairs at Princeton.
“As the world warms, risks will increase across a variety of fronts, and the threat to coastal infrastructure in the face of an already-rising sea level and potentially stronger hurricanes could be one of the most costly unless we are able to anticipate and reduce vulnerability,” Oppenheimer said.
Lead author Ning Lin, an assistant professor of civil and environmental engineering, said that knowing the frequency of storm surges may help urban and coastal planners design seawalls and other protective structures. Lin, who received her Ph.D. from Princeton in 2010, began the project at Princeton then continued it as a postdoctoral fellow at MIT; the current report is based on her work at MIT. The study was funded by the National Oceanic and Atmospheric Administration and the Princeton Environmental Institute.