MICHELE NORRIS, host:
From NPR News, this is ALL THINGS CONSIDERED. I'm Michele Norris.
Climate negotiators are meeting in Copenhagen to talk solutions on a global level. Meanwhile, people around the U.S. are pondering the impact climate change could have on the places where they live. Florida is one of the most vulnerable parts of the country when it comes to a rise in sea level.
As NPR's Greg Allen reports, officials are beginning to plan how to cope with that.
GREG ALLEN: Scientists say the sea level has been rising since the end of the last ice age. The concern now is how fast it's rising, and whether cities and natural ecosystems can adapt fast enough to avoid being devastated.
Mr. CHRIS BERG (Nature Conservancy): When you hear predictions of up to three or four feet over the next century, it really makes you nervous for the future of this place.
ALLEN: Chris Berg is with the Nature Conservancy in the Florida Keys. With an average elevation of just three or four feet, there are few places in America where the rising sea level is a bigger threat. We are on Big Pine Key, one of the chain's largest and most environmentally diverse islands. It's a place that's already been changed by the accelerating sea level rise. Berg takes me to a spot not far from the island's coast that used to be pine forest. Now, it's tidal wetlands � home to a few salt-tolerant plant species and the desiccated remnants of the old forest.
Mr. BERG: This stump is a pine tree � was a pine tree. Now, it's an old weathered pine stump. And it's literally 100 feet or more away from the nearest living live pine. At one time, pines could live out here in what is now a mangrove marsh.
ALLEN: At risk are more than a few pines. The Keys are home to many plants and animals that are found nowhere else in the world. The Nature Conservancy is working to develop special elevation maps for the Keys and other sensitive areas in Florida that will show what spots are most vulnerable and where action is needed to buy time for endangered ecosystems. It's becoming increasingly clear in Florida that more than just a few islands will be affected by the rising sea level.
Mr. FRANK ACKERMAN (Senior Economist, Stockholm Environment Institute): It's like our map of the area vulnerable to 27 inches of sea level rise looks like someone took a razor to the state right above Miami and sliced off everything below that.
ALLEN: Frank Ackerman is a senior economist at the Stockholm Institute who has studied what impact climate change and sea level rise will have on Florida. His model calls for a sea level rise of just over two feet by 2060. Under that scenario, Ackerman says Florida stands to lose almost 10 percent of its land area and the homes of 1.5 million people.
Mr. ACKERMAN: The vulnerable zone that's vulnerable to 27 inches turns out to include a whole lot of buildings that people would probably rather save. There's residential real estate worth $130 billion in that, half of Florida's beaches, two nuclear reactors, three prisons, 37 nursing homes, and on and on.
ALLEN: Ackerman has added up the impact more powerful hurricanes, higher average temperatures and declining tourism will have on Florida. He says the cost of inaction � doing nothing to slow climate change and sea level rise � would add up to $345 billion, or five percent of Florida's total income, by 2100.
In South Florida, Miami-Dade County set up a task force to look at the issue. It's adopted some recommendations, requiring greater use of hybrids, for example, but so far, it's shied away from tough decisions on zoning and development. And that worries Hal Wanless. He's chair of the geological sciences department at the University of Miami and an adviser to the county on sea level rise. In his office at the university, he brings up a map on his computer showing the impact a five-foot sea level rise would have on South Florida. Miami Beach and nearly all of the Keys are gone. Most of Miami-Dade County and much of Broward are underwater.
Mr. HAL WANLESS (Chairman, Geological Sciences, University of Miami): And it's going to just become increasingly risky to live in a place like Florida. Our roads are going to have to be elevated.
ALLEN: On this map, basically, Miami is an island now, from the rest�
Mr. WANLESS: It absolutely is.
ALLEN: In South Florida, keeping the sea at bay through the use of levees and pumps, along the lines of New Orleans or the Netherlands, is not really an option. This is a metropolitan region built on porous limestone that readily allows rainwater to soak in. Conversely, Wanless says, it also readily allows a rising water table to percolate up to the surface.
Mr. WANLESS: If we have rise in sea level, it will come right up through. I remember Hurricane Betsy, in the lower areas where the storm surge came right up through the ground. It didn't necessarily just wash across the surface, it came right up through. There's no way to put a levee around South Florida and really keep the water out.
ALLEN: Representatives of South Florida's four counties recently met and agreed to work together on strategies to cope with climate change and sea level rise. Miami-Dade County Commissioner Katy Sorenson says so far, communities have mostly focused on what they can do to stop contributing to global warming. Now, she says, it's time to begin thinking about how cities will adapt to the coming changes.
Ms. KATY SORENSON (County Commissioner, Miami-Dad): Part of the adaptation is going to mean actually doing building codes requiring people to have a higher foundation, because if we're going to have sea level rise, we're going to have to have communities that are built - literally built up. Flooding is going to become a commonplace phenomenon. It's common enough now. But just as California is fighting wildfires now almost year-round, we're going to be fighting flooding year-round. And we're going to have to adapt to that as well.
ALLEN: And the concerns are not just in South Florida. The Army Corps of Engineers recently published guidance for its staff, directing them to consider the impact a rise in sea level will have on all corps projects nationwide.
Greg Allen, NPR News, Miami.
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