Antarctica's Ice Discharge will be Major Contributor to Sea Level Rise
Antarctica's ice discharge could become a major contributor to the global sea level rise within this century, adding up to an extra 37 centimeters, which is more so than previously thought, according to a new study.
"If greenhouse gases continue to rise as before, ice discharge from Antarctica could raise the global ocean by an additional one to 37 centimeters in this century already," lead author Anders Levermann, of the Potsdam Institute for Climate Impact Research, said in a statement. "Now this is a big range - which is exactly why we call it a risk: Science needs to be clear about the uncertainty, so that decision makers at the coast and in coastal megacities like Shanghai or New York can consider the potential implications in their planning processes," he added.
Combining state-of-the-art climate models and observational data with various ice models, scientists for the first time provided a comprehensive estimate on the full range of Antarctica's potential contribution to global sea level rise.
They analyzed how rising global mean temperatures resulted in a warming of the ocean around Antarctica, thus influencing the melting of the Antarctic ice shelves. Currently, Antarctica only contributes less than 10 percent to global sea level rise and is therefore a minor contributor. Right now warming oceans and melting mountain glaciers are the number one threats to rising sea levels.
But this study shows that Antarctica, along with Greenland ice sheets, have the potential to elevate sea level by several meters - over several centuries.
In accordance with the latest projections released by the International Panel on Climate Change (IPCC), Antarctica will add 0 to 23 centimeters to global sea level rise - and that's being generous, believing that countries in the United Nations will reach their target of limiting temperature rise to 2 degrees Celsius (36 Fahrenheit).
If sea levels were to rise by as much as this report indicates, people living along the coast especially are in deep trouble.
"Rising sea level is widely regarded as a current and ongoing result of climate change that directly affects hundreds of millions of coastal dwellers around the world and indirectly affects billions more that share its financial costs," said co-author Robert Bindschadler from the NASA Goddard Space Flight Center.
Earlier research may have shown that Antarctica will play a role in global sea level rise, but this study shows that it "could become the dominant cause of sea level rise much sooner," according to Levermann.
The study's findings were published in the journal Earth System Dynamics.