The Greenland Ice Sheet is the second-largest body of ice on Earth. It covers an area about five times the size of New York State and Kansas combined, and if it melts completely, oceans could rise by 20 feet. Coastal communities from Florida to Bangladesh would suffer extensive damage.
Now, a new study is revealing just how little we understand this northern behemoth.
Led by geophysicist Beata Csatho, UB associate professor of geology, the research provides what the authors think is the first comprehensive picture of how Greenland’s ice is vanishing. It suggests that current ice sheet modeling studies are too simplistic to accurately predict future sea level rise, and that Greenland may lose ice more rapidly in the near future than previously thought.
“The great importance of our data is that for the first time, we have a comprehensive picture of how all of Greenland’s glaciers have changed over the past decade,” Csatho says.
“This information is crucial for developing and validating numerical models that predict how the ice sheet may change and contribute to global sea level over the next few hundred years,” says Cornelis J. van der Veen, professor in the Department of Geography at the University of Kansas, who played a key role in interpreting glaciological changes.
The project was a massive undertaking, using satellite and aerial data from NASA’s ICESat spacecraft and Operation IceBridge field campaign to reconstruct how the height of the Greenland Ice Sheet changed at nearly 100,000 locations from 1993 to 2012.
Ice loss takes place in a complex manner, with the ice sheet both melting and calving ice into the ocean.
The study had two major findings:
- Scientists were able to provide new estimates of annual ice loss at high spatial resolution (see below).
- The research revealed that current models fail to accurately capture how the entire Greenland Ice Sheet is changing and contributing to rising oceans.
The second point is crucial to climate change modelers.
Today’s simulations use the activity of four well-studied glaciers — Jakobshavn, Helheim, Kangerlussuaq and Petermann — to forecast how the entire ice sheet will dump ice into the oceans.
But the new research shows activity at these four locations may not be representative of what is happening with glaciers across the ice sheet. In fact, glaciers undergo patterns of thinning and thickening that current climate change simulations fail to address, Csatho says.
Continue reading at the University of Buffalo.
Greenland image via Shutterstock.