New York City was worried about sea level rise when it issued new recommendations this year that future buildings and other structures that are expected to last through the end of the century be raised 3 feet above current requirements. Credit: FEMA National Flood Hazard Layer
New York City is at increasing risk from storm surge flooding as sea level rises. Hurricane Sandy provided a preview of what the city could soon see more often.
Climate change is dramatically increasing the risk of severe flooding from hurricanes in New York City, to the extent that what was a once-in-500-years flood when the city was founded could be expected every five years within a couple of decades.
Throughout the century, of course, the risk of flooding increases as sea levels are expected to continue to rise.
These are the findings of a study published today that modeled how climate change may affect flooding from tropical cyclones in the city. The increased risk, the authors found, was largely due to sea level rise. While storms are expected to grow stronger as the planet warms, models project that they’ll turn farther out to sea, with fewer making direct hits on New York.
However, when sea level rise is added into the picture, “it becomes clear that flood heights will become much worse in the future,” said Andra J. Garner, a postdoctoral researcher at Rutgers University and the lead author of the study.
The paper, published in the Proceedings of the National Academy of Sciences, combines the high-emissions scenario from the Intergovernmental Panel on Climate Change with newer research that assumes more dramatic melting of Antarctic ice sheets to come up with a worst-case scenario for sea level rise. The projection shows waters surrounding New York rising anywhere from about 3 to 8 feet by 2100.