Nature - Greenland Ice Loss Since 1900 +/- 9 Trillion Tons; Melt Rate Doubled 2003-10 Vs. 20th Cent.
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). That’s over 9 trillion tons in total. And moreover, 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. The complex work involved inferring the loss of mass of the total ice sheet over a very large stretch of time using a merger of multiple information sources — the distinct marks left by retreating glaciers on the landscape, extensive aerial photography from 1978 through 1987, and — beginning in 1983 — satellite and aircraft observations.
All were merged to provide the new mass loss estimates. “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. The result is not only a better understanding of Greenland’s massive, centennial contribution to sea level rise, but also disturbing confirmation that its loss of mass is now accelerating.
“We find that 2003–2010 mass loss not only more than doubled relative to the 1983–2003 period, but also relative to the net mass loss rate throughout the twentieth century,” the study notes. It states that mass loss in this most recent period, ending in 2010, was 186 gigatons per year on average, though other estimates have put that number even higher for the most recent years. NASA currently states that Greenland is losing 287 billion tons of ice per year.
EDIT
https://www.washingtonpost.com/news/energy-environment/wp/2015/12/16/greenland-has-lost-a-staggering-amount-of-ice-and-its-only-getting-worse/