New research suggests climate change has greatly increased the risk storm-related flooding in New York City.
Hurricane Sandy caused major damage in NYC in the autumn of 2012, and this new research suggests similar events could occur in the future, Pennsylvania State University reported.
"We wanted to look at the impact of climate change on sea level and storm characteristics to see how that has affected the storm surge on the Atlantic coast, specifically in New York City," said Andra Reed, graduate student in meteorology, Penn State. "Hurricane Sandy was the motivating factor."
To make their findings, a team of researchers looked at a combination of models and paleoclimate data to outline the history of storm surges in the region. They used sediments and foraminifera (tiny marine organisms) to determine past changes in sea level. Using this data, the team created simulated tropical cyclone histories spanning the past 1,000 years, this model was then fed into a model of storm surges.
"In the pre-anthropogenic era, the return period for a storm producing a surge of 2.81 meters (9 feet) or greater like Sandy at the Battery would have been about 3,000 years," Reed said. "We found that, in the anthropogenic era, the return period for this same storm surge height has been reduced to about 130 years."
Before Hurricane Sandy, the largest recorded surge in New York City's Battery Park area was a 10 foot surge that occurred in 1938. During this surge only a half-inch of water breached the sea wall at Battery Park, during Hurricane Sandy so much water breached the sea wall that it flooded nearby subway systems.
The researchers believe factors behind the increased storm surge and flooding in the region included: the state of the tide and sea level; the strength of the surge; and the size of the storm.
"Sea level is rising because of climate change," said Michael Mann, distinguished professor of meteorology, Penn State. "But climate change also appears to be leading to larger and more intense tropical storms."
The findings were published in a recent edition of the journal Proceedings of the National Academy of Sciences.
