Understanding the specifics of how global climate change will affect any one specific region is tricky, but two researchers have tackled the issue of what will happen to Greenland over the next century, and the news is not encouraging.
“We put Greenland under a microscope to see what accounts for melting and for ice mass changes in different regions,” said Dr. Marco Tedesco, associate professor of earth and atmospheric sciences at The City College of New York, who worked in collaboration with Xavier Fettweis of the University of Liege, Belgium.
Tedesco and Fettweis used a regional climate model and the output of three separate global climate models to produce a fine-scale mode that gave them a high-resolution picture of Greenland’s future.
They thrust their simulated Greenland into two future carbon dioxide scenarios: a concentration of carbon dioxide in the atmosphere projected for the end of the century of 850 parts per million which approximates our current rate of increase, versus a more aggressive projection of 1370 parts per million.
In both scenarios the Greenland ice sheet lost more ice and snow to melting than it could acquire.
Basins on the southwest and north coasts both suffered the greatest losses, with temperatures needing only to increase by 0.6 to 2.16 degrees Celsius (1.8-3.9 ° F) to push us over the edge where there is more loss than gain.
While a dramatic demonstration of what might happen to one location, the research has it’s limits.
“They don’t take into account progressive effects of the changing elevations and topography and the acceleration of ice sheet movement,” Tedesco said.
So while we know that Greenland is likely to melt in a warming world, the direct affect it has on nearby ocean circulation and salinity, or the impact such a melt will have on speeding further melting is unknown.
“Some areas will be 400 meters below the current elevation just because of melting. This might very well impact the speed and amount of ice that is flowing to the ocean. It would increase the rate of melting, because conditions get warmer at lower elevations” he noted. “Imagine an ice cream that is melting much faster in one area. This will change the shape of the ice mass over Greenland.”