Over the next two millennia, the melting of the Antarctic ice sheet is projected to contribute to half of all sea-level rise. (Photo: Rita Williaert/ cc/ Flickr)
"Greenhouse gases emitted today will cause sea level to rise for centuries to come," concluded a team of scientists behind a new
study published Monday in the
National Academy of Sciences.
The study, conducted by a group from Germany's
Pottsdam Institute for Climate Impact, found the sea levels may rise by as much as 2.3 meters (roughly 7.5 feet) with each degree Celsius that global temperatures increase.
"Sea-level rise might be slow on time scales on which we elect governments, but it is inevitable and therefore highly relevant for almost everything we build along our coastlines, for many generations to come,” cautioned Anders Levermann, lead author of the study.
The study is the first of its kind to combine evidence from climate history with computer simulations of contributing factors to long-term sea-level increases: thermal expansion of oceans, the melting of mountain glaciers and the melting of the Greenland and Antarctic ice sheets.
According to their findings, though thermal expansion and melting glaciers are thus far the greatest contributing factors to sea-level change, the melting of the ice sheets will be the dominant contributors within the next two millennia.
As Levermann explains, because of their enormous mass, the oceans and ice sheets are slow in responding to the global temperature increase. However, like a rolling stone, "once heated out of balance, they simply don’t stop."
“CO2, once emitted by burning fossil fuels, stays an awful long time in the atmosphere,” he adds. “Consequently, the warming it causes also persists.”
Scientists predict that as much as half of total sea-level rise will come from ice-loss in Antarctica, with Greenland melting contributing another 25 percent.
Describing the impact of the study's predictions, David Vaughan, head of the
ice2sea project,
told Reuters the most grave consequences will be seen in the frequency and severity of storms.
"It's not about chasing people up the beach or the changing shape of coastlines," he said. "The big issue is how the storms will damage our coasts and how often they occur. That'll increase even with small levels of sea rise in coming decades."
“Continuous sea-level rise is something we cannot avoid unless global temperatures go down again,” Levermann adds. “Thus we can be absolutely certain that we need to adapt.”
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