Tuesday, August 7, 2012

Fast-rising seas demand new flood plans and smart zoning

Bloomberg View: A new analysis of worldwide temperatures over the past 60 years has found more evidence that global warming is already upon us, and is responsible for extreme heat waves -- such as the ones in Russia in 2010 and in Texas and Oklahoma last year.

Naturally, this refocuses attention on the current U.S. drought. Left out of the discussion, however, is another, equally serious and already pressing consequence of human- induced climate change: sea-level rise. On all coasts, we face a huge and building threat from too much water.

With oceans expanding from the heat and with glaciers large and small melting away, sea levels have climbed more than 8 inches since 1880, and the current rate is about an inch and a quarter every decade. Many scientists expect the water to rise at least 2 feet to 3 feet more by the end of this century.

This won’t happen evenly everywhere. One hot spot is the East Coast of the U.S., where the land is sinking and nearby ocean currents are slowing, causing the water to rise faster. From Cape Hatteras, North Carolina, up through Cape Cod, Massachusetts, in the past half century, the speed of increase in water level has been three to four times the global average. Yet the North Carolina Legislature has essentially banned relevant state agencies from taking projections of accelerating sea-level rises into account in policy making.

Such shortsightedness on the part of public officials is not only irrational, it’s foolish. By 2030, in many places on the U.S. coast, sea level rise due to global warming will have more than doubled the risk of floods 4 feet or more over high tide. Lands below this 4-foot mark are now home to 5 million Americans, as well as vital infrastructure such as power plants, bridge access ramps and railroads -- not to mention schools, hospitals, parks and countless seaside ice cream stands....

Race Point Beach on Cape Cod, shot by Daniel Schwen, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 2.5 Generic license

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