Antarctica May Lift Sea Level Faster in Threat to Megacities

Antarctica glaciers melting because of global warming may push up sea levels faster than previously believed, potentially threatening megacities including New York and Shanghai, researchers in Germany said.

Antarctica’s ice discharge may raise sea levels as much as 37 centimeters (14.6 inches) this century if the output of greenhouse gases continues to grow, according to a study led by the Potsdam Institute for Climate Impact Research.  The increase may be as little as 1 centimeter, they said.

“This is a big range, which is exactly why we call it a risk,” Anders Levermann, the study’s lead author, said in a statement.  “Science needs to be clear about the uncertainty so that decision makers at the coast and in coastal megacities can consider the implications in their planning processes.  ”The Potsdam institute’s projections for this century’s sea level contribution are “significantly higher” than the latest upper-end projections from the Intergovernmental Panel on Climate Change, it said.

Even a scenario with ambitious climate policies to cap warming to 2 degrees Celsius (3.6 degrees Fahrenheit) since industrialization, the contribution of Antarctica to global sea level rise covers a range of 0 to 23 centimeters, it said.  The 2-degree threshold has been agreed as a target by 194 nations involved in climate treaty talks and compares with the current trajectory which the United Nations predicts will lead to warming of at least 3.7 degrees Celsius.

Antarctica May Lift Sea Level Faster in Threat to Megacities