Rising seas will affect major U.S. coastal cities by 2100: research

February 17, 2011 12:28 pm 

WASHINGTON, Feb. 17 — Rising sea levels could threaten an average of nine percent of the land within 180 U.S. coastal cities by 2100, according to a new research led by University of Arizona (UA) scientists.

The Gulf and southern Atlantic coasts could be particularly hard hit. Miami, New Orleans, Tampa and Virginia Beach could lose more than 10 percent of their land area by 2100, according to the research, which will be published online this week in Climatic Change Letters.

The latest scientific projections indicate that by 2100, the sea level will rise about one meter — or even more. At the current rate of global warming, sea level is projected to continue rising after 2100 by as much as one meter per century.

"According to the most recent sea-level-rise science, that's where we're heading," said lead researcher Jeremy Weiss, a senior research specialist in the UA's department of geosciences. " Impacts from sea-level rise could be erosion, temporary flooding and permanent inundation."

The coastal municipalities the team identified had 40.5 million people living in them, according to the 2000 U.S. Census. Twenty of those cities have more than 300,000 inhabitants. Using data from the U.S. Geological Survey, the scientists were able to calculate how much land area from the 180 municipalities could be affected by one to six meters of sea-level rise.

"With the current rate of greenhouse gas emissions, the projections are that the global average temperature will be eight degrees Fahrenheit warmer than present by 2100," said Weiss.

"That amount of warming will likely lock us into at least four to six meters of sea-level rise in subsequent centuries, because parts of the Greenland and Antarctic ice sheets will slowly melt away like a block of ice on the sidewalk in the summertime."

At three meters, on average more than 20 percent of land in those cities could be affected. Nine large cities, including Boston and New York, would have more than 10 percent of their current land area threatened. By six meters, about one-third of the land area in U.S. coastal cities could be affected.

"Our work should help people plan with more certainty and to make decisions about what level of sea-level rise, and by implication, what level of global warming, is acceptable to their communities and neighbors," said co-author Jonathan Overpeck, a UA professor of geosciences. (PNA/Xinhua)



Comments are closed.