Within this century, ice melting in the Antarctic alone could cause the global sea level to rise up to three times as much as it did in the entire last century, the Potsdam Institute of Climate Impact Research (PIK) announced on Friday.
“While we saw about 19 centimeters of sea-level rise in the past 100 years, Antarctic ice-loss could lead to up to 58 centimeters within this century,” said lead-author of the study Anders Levermann from the PIK and Columbia University’s Lamont-Doherty Earth Observatory (LDEO) in New York.
According to the PIK, other factors that would lead to a further rise of the sea level were the thermal expansion of the ocean water under global warming and the melting of mountain glaciers which had caused most of the sea level rise so far.
The scientists believe that the Antarctic would now become the biggest factor in sea level rise, according to the study published in the journal Earth System Dynamics of the European Geosciences Union (EGU) on Friday.
“The Antarctica factor turns out to be the greatest risk, and also the greatest uncertainty, for sea-levels around the globe,” said Levermann.
Assuming a scenario with constant greenhouse gas emissions, a “very likely” range of sea level rise in this century caused by Antarctic ice melting would be between 6 and 58 centimeters.
If greenhouse gas emissions were to be “reduced rapidly”, the range would only be between 4 and 37 centimeters, according to the study.
The Antarctic ice sheet has the potential to raise global sea levels by tens of meters. “What we know for certain,” said Levermann, “is that not stopping the burning of coal, oil and gas will drive up the risks for coastal metropolises from New York to Mumbai, Hamburg or Shanghai.”