Advertisement
Governor Andrew M. Cuomo toured the Hugh L. Carey Tunnel (formerly known as the Brooklyn Battery Tunnel) on Oct. 30, 2012, with MTA Chairman and CEO Joseph J. Lhota and Jim Ferrara, President of MTA Bridges and Tunnels. The tunnel flooded during Hurricane Sandy. Photo: Metropolitan Transportation Authority / Patrick Cashin.

The good news: storm surges in New York City for the next two centuries remain fairly constant. The bad news: water levels will already be higher to begin with.

The same models of a globally changing climate predict that overall flooding in the Big Apple will be worse than ever, and so-called 500-year storm flooding will happen every five years by the mid-point of our century.

Those are the findings of a Rutgers University-led study published today by the Proceedings of the National Academy of Sciences – about a week before the fifth anniversary of the regional devastation wrought by Hurricane Sandy.

“(The models) indicate that there will be minimal change in storm-surge heights from 2010 to 2100 or 2300, because the predicted strengthening of the strongest storms will be compensated by storm tracks moving offshore at the latitude of New York City,” they write.

“However, projected sea-level rise causes overall flood heights associated with tropical cyclones in New York City in coming centuries to increase greatly compared with preindustrial or modern flood heights,” they add.

The sea-level rise was predicted by methodology established by one the authors, Robert Kopp, in a previous paper published in the open-access journal Earth’s Future in 2014.

The probabilistic outcomes of sea level at a global and local level are determined by the loss of ice in Greenland and Antarctica, as well as glaciers and ice caps worldwide. For these predictions, they used three coupled computer modeling systems in concert.

Although hurricanes may be stronger, and may take new tracks in a warming climate, New York City is unlikely to get a reprieve, they find. Overall sea-level rise is expected to disproportionately affect Manhattan (the focus of the study is at the Battery in NYC), they add.

“Sea level rise will greatly increase future flood risk for NYC, where sea level rise is project to be more rapid than the global mean,” they write. “Sea levels are expected to continue rising for at least the next several centuries, more than offsetting any potential decreases in storm-surge heights.”

Already, the 500-year storms occur every 25 years, the Rutgers team finds. But that frequency is likely to increase, bringing the same level of flooding every five years, they conclude.

Benjamin Horton, one of the authors of the current study, has previously published on the frequency of such storm levels with colleagues from other institutions. Previous Rutgers research, with similar models, has found that oceans are on track to potentially rise more than four feet by the end of this century, as reported early last year in the PNAS.

Advertisement
Advertisement