New report: Sea levels on US coasts are rising sharply

The seas along the Atlantic coast rose at their fastest rate in 2000 years in the 20th century. A new report now makes it clear: Areas will be flooded where there were previously no floods.

Over the next 30 years, sea levels on the American coast will rise at the rate they did in the entire 20th century. Costly flooding regularly hits major East Coast cities, even on sunny days, warns a government report now released by NOAA and six other federal agencies.

The sea level will then rise by 0.25 to 0.3 meters, and in parts of the US states of Louisiana and Texas by as much as 0.45 meters. “Sea level rise is here,” said Nicole LeBoeuf, director of NOAA. The projected increase is particularly alarming given that seas along the Atlantic coast have risen at their fastest rate in 2,000 years in the 20th century.

“Whole new level of flooding”

40 percent of the American population lives on the coast. However, the worst of long-term sea-level rise from melting ice sheets in Antarctica and Greenland will likely not occur until after 2100, said oceanographer William Sweet, the report’s lead author.

“The coastal flooding that we’re seeing now in the United States will be on a whole new scale in a couple of decades,” said University of Wisconsin-Madison geoscientist Andrea Dutton, a sea-level rise specialist who does not predict was involved in the federal report. “We can see this freight train coming from more than a mile away. The question is, will we continue to slide houses into the sea.”

increase of one meter by the end of the century

By mid-century, “moderate” flooding will replace smaller floods that are already regular in some areas, the researchers warn. “There will be flooding in areas that have not previously experienced flooding,” said William Sweet. “Many of our major metropolitan areas on the East Coast will be increasingly at risk.”

And that’s only until 2050. The report predicts an average sea level rise of about three feet in the United States – more in the east, less in the west – by the end of the century.