2015-12-16. Greenland has lost a staggering amount of ice — and it’s only getting worse.

posted Dec 19, 2015, 6:51 PM by Alan Gould
By Chris Mooney, Washington Post. For GSS Climate Change chapter 8. Excerpt: A massive new study by 16 authors has calculated just how much ice the Greenland ice sheet has lost since the year 1900. And the number, says the paper just out in the journal Nature, is astounding: 9,103 gigatons (a gigaton is a billion metric tons). ...the rate of loss has been increasing, the research finds, with a doubling of annual loss in the period 2003 to 2010 compared with what it was throughout the 20th century. The study was led by Kristian K. Kjeldsen of the Natural History Museum of Denmark at the University of Copenhagen.  ... “It’s the first observational based study that shows where Greenland has lost its mass over the last 110 years,” said Kurt H. Kjær, the paper’s senior author and also of the Natural History Museum of Denmark at the University of Copenhagen. ...Ice loss from Greenland today occurs through two key mechanisms — melting on the surface of the ice sheet followed by runoff into the ocean, and large calving events at marine based glaciers, which are followed by more flow of ice outward from behind them. ...The new research also suggests that Greenland was a major player in the global sea level budget throughout the last century, and accounts for much sea level rise that the U.N.’s Intergovernmental Panel on Climate Change had previously not attributed to the Greenland. ...Greenland would have contributed about 2.5 centimeters of sea level rise over the period — roughly an inch. That may not sound like much, but it’s enough water to submerge the entire U.S. interstate highway system 98 feet deep — and to do so 63 times over, says Jason Box, a professor with the Geological Survey of Denmark and Greenland. Taken in total, a melting of the entire Greenland ice sheet would lead to roughly 20 feet of sea level rise. ...The world’s recent Paris goal of keeping warming well below 2 degrees Celsius (or even better, 1.5 degrees Celsius), if achieved, may just be enough to prevent a scenario in which a total melt occurs over time. “The ice sheets are doomed in plus 3 Celsius world,” says Box....  https://www.washingtonpost.com/news/energy-environment/wp/2015/12/16/greenland-has-lost-a-staggering-amount-of-ice-and-its-only-getting-worse/