New York's Worst Hurricane Fears Confirmed in New Study

NEW YORK, New York, October 26, 2006 (ENS) The 2004 movie The Day After Tomorrow painted an apocalyptic vision of a New York City battered by hurricanes, tidal waves and floods induced by global warming. A new study being presented at a science meeting this week provides a detailed picture of sea level rise around New York by the 2050s and paints a scenario similar to that dramatized by the big budget blockbuster.

Rising sea levels combined with the storm surge of a category three hurricane would leave much of a 2050s New York underwater and the city's entire metropolitan transportation system shut down, say scientists Cynthia Rosenzweig and Vivien Gornitz.

Rosenzweig and Gornitz are part of a team at NASA's Goddard Institute for Space Studies and New York's Columbia University investigating future climate change impacts in the metropolitan area.


Lower Manhattan would be inundated by hurricanes combined with rising sea levels by 2050, new research suggests. (Photo courtesy
They have been working with New York City's Department of Environmental Protection since 2004, using computer models to simulate future climates and sea level rise. Recently, computer modeling studies have provided a more detailed picture of sea level rise around New York by the 2050s.

Gornitz is presenting the team's findings at the annual meeting of the Geological Society of America in Philadelphia this week.

Inhabited by more than eight million people, New York City has long been an area of concern during hurricane season, which usually runs from June 1 to November 30. It has been hit before.

A category four storm which made landfall in the Caribbean on September 3, 1821 led to a 13 foot storm surge causing widespread flooding in lower Manhattan.

The "Long Island Express" or "Great Hurricane of 1938," a category three, tracked across central Long Island and ripped into southern New England on September 21, 1938, killing nearly 700 people. The storm pushed a 35 foot high wall of water ahead of it, sweeping away protective barrier dunes and buildings.


Waves thrash a seawall along the Atlantic coast during the Great Hurricane of 1938. (Photo courtesy NOAA)
During most of the 20th century, sea levels around the world have been rising by 1.7 to 1.8 millimeters (0.07 inches) per year. That figure has increased to nearly 3 mm (0.12 in) per year within the last decade.

Warming of the world's oceans, melting of mountain glaciers and polar ice caps are thought to be responsible for the rising sea levels.

The 2001 report of the Intergovernmental Panel on Climate Change found that a global warming of 1.4 to 5.8 degrees Celsius (2.5 to 10.4 Fahrenheit) could lead to a sea level rise of 0.09 to 0.88 meters (four inches to 2.9 feet) by 2100.

"With sea level at these higher levels, flooding by major storms would inundate many low-lying neighborhoods and shut down the entire metropolitan transportation system with much greater frequency," said Gornitz.

As sea levels rise, so does the risk of a hurricane storm surge in New York City, Gornitz said.

Storm surge is an above normal rise in sea level accompanying a hurricane. Hurricanes are categorized on the Saffir-Simpson scale, from one to five, with five being the strongest and most destructive.

Rosenzweig and Gornitz's two year study used the Goddard Institute's Atmosphere-Ocean Model, a computer program that simulates the Earth's climate. Based on previous research by Columbia University scientists for the U.S. Global Change Research Program in 2001 and the Intergovernmental Panel on Climate Change, this model projects a sea level rise of 15 to 19 inches by the 2050s in New York City.

Adding as little as 1.5 feet of sea level rise by the 2050s to the surge for a category three hurricane on a worst-case track would cause extensive flooding in many parts of the city, said Gornitz.


Category 2 hurricane storm surge simulation at the Brooklyn Battery Tunnel in New York City. (Photo courtesy NOAA)
Areas potentially under water include Lower Manhattan, much of southern Brooklyn and Queens, portions of Long Island City, Astoria, Flushing Meadows-Corona Park, Queens, the Rockaways, Coney Island, and eastern Staten Island from Great Kills Harbor north to the Verrazano Bridge.

For perspective, Rosenzweig and Gornitz point to a 1995 study by the U.S. Army Corps of Engineers, which looked at what surge levels for hurricanes of categories one through four would do to the city.

According to the 1995 Metro New York Hurricane Transportation Study, a category three hurricane on a worst-case track could create a surge of up to 25 feet at JFK Airport, 21 feet at the Lincoln Tunnel entrance, 24 feet at the Battery, and 16 feet at La Guardia Airport. These figures do not include the effects of tides or the additional heights of waves on top of the surge.

The study used a computer model known as SLOSH - Sea, Lake and Overland Surges from Hurricanes. It is run by the National Hurricane Center to estimate storm surge heights resulting from historical, hypothetical, or predicted hurricanes by taking into account pressure; size, forward speed, track and hurricane winds.


Hurricane Floyd hit the Atlantic coast on September 15, 1999. Almost twice the size of typical Atlantic hurricanes, Floyd claimed 51 lives and left thousands homeless. (Photo courtesy NASA)
"This entire work is solutions oriented," said Rosenzweig of the study presented this week. "It's about helping NYC DEP and other New York City agencies make better preparations for climate extremes of today, and changing extremes of the future.

"The report will help us determine how can we do better job now, as well as in the future."

New York City officials are testing and refining preparedness plans and emergency response protocols, as well as strengthening coordination between emergency responders at the city, state and federal levels.

On Sunday, the New York City Office of Emergency Management, OEM, and the New York City Department of Homeless Services hosted HURREX, a multi-agency field exercise designed to test the city's response to a hurricane or large scale storm.

The third in a series of exercises designed to determine the effectiveness of the city's Coastal Storm Plan and to identify areas for improvement, HURREX was staged at New York City College of Technology and two other New York City Department of Education facilities in Brooklyn.

Over 800 people participated in HURREX. Coordinated by OEM, the seven-hour, real-time drill focused on the components of the City's Coastal Storm Plan that relate to the setup and operation of hurricane shelters for evacuees.

The drill, which involved the opening of an evacuation center and two hurricane shelters, was staffed by over 130 City employees from the 18 agencies that would participate in sheltering operations during a real coastal storm emergency.

"Good emergency management means being prepared for every eventuality, said Deputy Mayor for Administration Edward Skyler. "This exercise tested an incredibly comprehensive response plan, so that if the real thing ever happens, we are ready."