According to a study published in Nature last week, sea levels could rise twice as much as previously anticipated by 2100 if carbon dioxide emissions remain unchecked. Current consensus projects that sea levels could rise by just under a meter by the end of the century; however, this figure does not factor in a substantial contribution from Antarctica. The new study, conducted by Rob DeConto of University of Massachusetts, Amherst and David Pollard of Pennsylvania State University, however, does account for the melting of ice on Greenland and Antarctica. Moreover, the study showed that the melting on Antarctica could cause sea levels to rise by more than 15 meters by 2500. DeConto and Pollard are drawing praise from colleagues for their computer models used to figure out how Antarctica had surrendered so much ice during two previous warm periods: the Eemian period (between 130,000 and 115,000 years ago) and the Pliocene (about 3 million years ago). Similar conditions in the future could lead to a rise in sea levels by nearly two meters by 2100.
Fellow scientists have also been wary of the study’s certainty, though. Eric Rignot, an Antarctica ice sheet expert and professor at the University of California, Irvine, cautioned that the dire consequences from the rise in sea level are not inevitable; rather, we are on track to head that way, considering the current rate of carbon dioxide emissions. Ben Strauss, the director of Climate Central’s program on sea level rise, warned of catastrophes in the next century unless greenhouse gas emissions are abated. Furthermore, coastal areas like South Florida, Bangladesh, Shanghai, Hampton Toads in Virginia, New Orleans, and Washington D.C. may experience significant problems in the nearer future. Although world leaders agreed to scale back greenhouse gas emissions in in Paris last year, Strauss believes that countries need to be more aggressive in reducing such emissions to save coastal cities. U.S. coastal cities like Boston and New York may be in particularly bad shape because of Antarctica’s gravity. It pulls the ocean toward it. When it loses significant mass, seas would surge back in opposite directions.