A new study has suggested that global
warming is expected to cause the sea level along the north-eastern U.S. coast to rise almost twice as fast as
global sea levels during this century.
This would put New York City at greater risk for damage from
hurricanes and winter storm surge.
The study was led by Jianjun Yin, a climate
modeler at the Center for Ocean-Atmospheric Prediction Studies (COAPS) at Florida State University, US.
According to Yin, there is a better than 90 percent chance
that the sea level rise along this heavily populated coast will exceed the mean
global sea level rise by the year 2100.
The rising waters in this region, perhaps by as much as 18
inches or more, can be attributed to thermal expansion and the slowing of the North Atlantic Ocean circulation because of warmer ocean
Yin and colleagues Michael Schlesinger of the University of Illinois
at Urbana-Champaign and Ronald Stouffer of Geophysical Fluid Dynamics
Laboratory at Princeton
University are the first
to reach that conclusion after analyzing data from 10 state-of-the-art climate
models, which have been used for the Intergovernmental Panel on Climate Change
(IPCC) Fourth Assessment Report.
"The northeast coast of the United States
is among the most vulnerable regions to future changes in sea level and ocean
circulation, especially when considering its population density and the
potential socioeconomic consequences of such changes," Yin said.
"The most populous states and cities of the
and centers of economy, politics, culture and education are located along that
coast," he added.
The researchers found that the rapid sea-level rise
occurred in all climate models whether they depicted low, medium or high rates
of greenhouse-gas emissions.
In a medium greenhouse-gas emission scenario, the New York City coastal
area would see an additional rise of about 8.3 inches above the mean sea level
rise that is expected around the globe because of human-induced climate change.
Thermal expansion and the melting of land
ice, such as the Greenland ice sheet, are
expected to cause the global sea-level rise.
The researchers projected the global
sea-level rise of 10.2 inches based on thermal expansion alone.
"Considering that much of the metropolitan
region of New York City is less than 16 feet above the mean sea level, with
some parts of lower Manhattan only about 5 feet above the mean sea level, a
rise of 8.3 inches in addition to the global mean rise would pose a threat to
this region, especially if a hurricane or winter storm surge occurs," Yin said.