Unprecedented Warming at the Top of the World

If human societies don’t sharply curb emissions of greenhouse gases, Greenland’s rate of ice loss this century is likely to greatly outpace that of any century over the past 12,000 years, a new study concludes.

Led by University at Buffalo geologist Jason Briner and published in the journal Nature, the study employs ice sheet modeling to understand the past, present and future of the Greenland Ice Sheet. The findings put the ice sheet’s modern decline in historical context for the first time, highlighting just how extreme projected losses for the 21st century could be.

The multidisciplinary team behind the study included researchers from UB, NASA, the University of Washington, Columbia University, the University of Montana and the University of California, Irvine. They used a cutting-edge ice-sheet model to simulate changes to the southwestern sector of the Greenland Ice Sheet, starting from the beginning of the Holocene Epoch some 12,000 years ago and extrapolating forward to 2100.

Scientists tested the model’s accuracy by comparing results of the model’s simulations to historical evidence. The projections matched up well with data tied to actual measurements of the ice sheet made by satellites and aerial surveys in past decades, as well as the group’s own field studies to identify the ice sheet’s boundaries from thousands of years ago.

The study makes an important contribution by creating the first timeline of the past, present and future of the Greenland Ice Sheet, says Briner, who describes the results as “eye-opening.”

The study provides evidence that the rate of ice loss for this century is not a result of natural variability, as many climate change skeptics speculate. According to the findings, the current rate will exceed that for any single century over the last 12,000 years—up to four times the highest natural rate of loss—if the world stays on its current course.

Despite these sobering results, one vital takeaway from the model’s future projections is that it’s still possible for people and countries around the world to make an important difference by cutting emissions, Briner says. But one thing, he says, is clear: “Americans need to go on an energy diet.”