One would be close to the Verrazano-Narrows Bridge. (The Thames Barrier in London performs such a role in a more modest way.) But the cost would probably exceed $10 billion; a barrier in Venice cost $7 billion.
-- Another recommendation would be tougher regulations on where industrial and chemical plants can be situated, improving the design of buildings to make lower levels flood-proof (known as freeboard in the insurance industry) and "soft edges" that better break wave action.
-- Stronger and maybe higher sea walls around more vulnerable parts of Manhattan might also help.
The current sea walls are about 4 to 5 feet above the average sea level. Many were built at the beginning of the last century. A New York Times article from August 1901 marveled at "The Massive Sea Wall Which Will Encompass Manhattan."
"It will be many generations, perhaps centuries, before the wall ... will have to be rebuilt or will even require any extensive repairs," the Times reported then. That was before climate change became part of the lexicon. New York City's "Vision 2020" plan warned that sea walls and other shoreline structures are likely to need more frequent repair because of more damaging storms.
Will Sandy drive political debate about climate change?
According to a recent Pew Research Center poll, 67% of Americans believe the Earth is warming.
That number is up slightly since 2010, but it's 10 percentage points less than in 2006. Among both Democrats and Republicans, the percentage has declined, as has the number (now 64%) who say it's a serious problem.
The lack of debate about climate change in the presidential election campaign has been "unfortunate," said the Nature Conservancy's Marshall.
But Marshall said she believes Americans are getting to the point of recognizing what they see for what it is.
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