One aspect of climate change that's already affecting people in various parts of the world is the slow but steady rise in sea level (via YaleE360):

Pacific and Indian Ocean atoll nations are already being abandoned because of the direct and indirect effects of sea level rise, such as saltwater intrusion into groundwater. In the Marshall Islands, some crops are being grown in abandoned 55-gallon oil drums because the ground is now too salty for planting. New Zealand is accepting, on a gradual basis, all of the inhabitants of the Tuvalu atolls. Inhabitants of Carteret Atoll have all moved to Papua, New Guinea.

Orrin Pilkey and Rob Young, authors of the book The Rising Sea observe that mainstream climate-change reports like the IPCC's have vastly underestimated the amount of sea-level rise we're likely to see this century. That's because most climate models don't account for the contributions from the melting of two of Earth's largest ice sheets in Greenland and Antarctica. Newer estimates, say the authors, suggest we're likely to see at least a three-feet rise—and should prepare for up to seven feet. (Bear in mind that a seven-foot vertical rise in sea level would translate into thousands of square miles of coastal land inundated, as any land below that elevation will be underwater.)

It's not as if U.S. government entities are ignoring the problem entirely, though they too are underestimating it—Rhode Island, California and Florida have all put out reports anticipating a three to five foot rise by 2100. The problem is that no one is bothering to change laws that would alter development practices:

Miami tops the list of most endangered cities in the world, as measured by the value of property that would be threatened by a three-foot rise. This would flood all of Miami Beach and leave downtown Miami sitting as an island of water, disconnected from the rest of Florida. Other threatened U.S. cities include New York/Newark, New Orleans, Boston, Washington, Philadelphia, Tampa-St Petersburg, and San Francisco... [M]ost coastal states continue to allow massive, irresponsible development of the low-lying coast. ...

Ironically, low-elevation Florida is probably the least prepared of all coastal states. Hundreds of miles of high rises line the state’s shoreline, and more are built every year. The state pours subsidies into coastal development through state-run insurance and funding for coastal protection. If a portion of those funds were spent adapting to sea level rise rather than ignoring it, Florida might be ready to meet the challenge of the next century.

This doesn't include the impacts on the Gulf Coast and the Mississippi River Delta, which will be devastated as well. Pilkey and Young recommend that the United States put a ban on construction in areas subject to inundation by future sea-level rise, relocate critical but threatened infrastructure, end government support for post-disaster coastal redevelopment, and take responsibility for addressing sea-level rise away from the Army Corps of Engineers, which has a "we can fix it" methodology.

But it's hard to see Congress stepping up to this challenge, mostly because it would require acknowledgement from all parties that climate change is real and altering the planet in significant ways. This may prove even harder than addressing carbon emissions, since you can't justify a ban on coastal development as boosting "energy independence." The deniers and skeptics will no doubt claim that addressing sea-level rise is ludicrous. In all likelihood, the West Antarctic ice shelf may have to collapse (something that could happen sooner than we think), before state and federal governments do more than publish reports.

(Flickr photo credit: jaeWALK)

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