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8 months ago

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Hazmat Science and

Hazmat Science and Public Policy with George Lane Rising tide in the Gulf of Mexico, caused by the ice melting in Antarctica, is creating the first climate refugees in Louisiana By George Lane In January of this year, the United States Department of Housing and Urban Development announced a $48 million grant for Isle de Jean Charles located on the vulnerable southern coast of Louisiana: the first allocation of federal tax dollars to move an entire community struggling with the impacts of climate change. 1 The resettlement plan is one of the first of its kind in the world, a test of how to respond to climate change in the most dramatic circumstances without tearing communities apart. Under the terms of the federal grant, the island’s residents are to be resettled to drier land, a community that currently does not exist. Louisiana officials have been coping with some of the fastest rates of land loss in the world, an area the size of Delaware has disappeared from south Louisiana since the 1930s. Unless significant changes are made, Louisiana will have the first climate refugees in the world. Donald Boesch and Virginia Burkett, coastal researchers with Louisiana connections, are widely respected for their expertise on why Louisiana’s coast is rapidly being flooded by the Gulf of Mexico. 2 Both believe that recently released Unless significant changes are made, Louisiana will have the first climate refugees in the world. research could hold the key to the success of that effort or its rapid demise. However, the surprising new study doesn’t involve levees, sediment diversions, oil and gas canals or any of the other issues usually debated when Louisiana’s coastal plan is discussed. It blames Antarctica, thousands of miles south of the Louisiana coast. 30 The research presents evidence that the world and Louisiana face a stark choice. If global temperatures do not rise more than 2 degrees Celsius by 2100, sea-level rise could be manageable and Louisiana’s coastal plan might succeed. Otherwise a sudden, dramatic melting of ice on Antarctica will add another 3 feet to the current prediction of a 3.5-foot rise in sea level by 2100, swamping most of the southern third of Louisiana. 3 It holds a key to the future of the Louisiana coast. The rate of ice loss projected for Antarctica could result in the loss of Louisiana’s coastal systems as we know them. What happens in Antarctica could determine what happens here in Louisiana. We’re definitely linked. It’s hard to imagine two locations with less in common. Louisiana is subtropical, green and home

to pelicans and hurricanes while Antarctica is freezing, white, and home to penguins and blizzards. Yet as soon as science confirmed that seas are rising because human actions are warming the atmosphere, researchers knew Antarctica would be critical to the future of coastal communities, especially the already sinking coast of Louisiana. Atmospheric warming is raising sea levels in two ways. First, water expands as it is warmed, and the oceans have been increasing in volume because of that. Second, water stored as ice in glaciers and ice shelves is now pouring into the oceans, further increasing their volume. Antarctica holds 90 percent of the world’s ice. Suddenly an isolated, little-visited continent became very, very important to Louisiana, and the world. Stretched across the bottom of the planet, Antarctica is huge, covering an area roughly the size of the United States and Mexico combined. Heaped on top of that vast land mass is ice averaging 7,000 feet in depth. Imagine a vast container of water with a faucet at the bottom. If the faucet only drips, it won’t change ocean levels much. But if opened wider and fixed in that position for centuries, most coastlines would drown. If all the ice in Antarctica melts, those same models show the oceans rising 200 feet, meaning Baton Rouge, Louisiana, now 80 miles north of New Orleans, would be on what’s left of the coast. Evidence has long existed that past episodes of dramatic increases in sea level were accompanied by sudden, huge losses of Antarctic ice. But the new and rapidly evolving science focusing on the complex forces at work on that continent had yet to nail down reliable mechanisms for the progression of ice loss. While our planet has been warming, the floating ice fields surrounding Antarctica have been growing in size in recent years. 31 These floating fields, composed of relatively recent snows, serve as bumpers protecting the massive land-based ice shelves from the warming ocean. They were one reason the United Nations’ Intergovernmental Panel on Climate Change said Antarctica would contribute little to the group’s “worst case” rise of 3.2 feet by the end of the century. That was shaken in January with the publication of a study titled “Contribution of Antarctica to past and future sea level rise.” 4 Researchers Robert DeConto and David Pollard had been struggling for years to determine why their computer models could not reproduce the dramatic melting that occurred 125,000 years ago under