(Reuters) – Greenland’s ice sheet lost a record mass last year, according to a study published on Thursday, a finding that could prompt scientists to redefine their worst-case scenario when assessing the effects of climate change .
FILE PHOTO: Crevasses form on top of the slippery slope of Helheim near Tasiilaq, Greenland, 19 June 2018. REUTERS / Lucas Jackson / File Photo
The rate of ice loss was slower over a two-year period amid cooler summers and higher snowfall in western Greenland through 2018. But last year, when warm air flowed north from lower latitudes, the frozen island experienced a record loss in its ice mass, geoscientist and glaciologist Ingo Sasgen of the Alfred Wegener Institute in Germany said.
That loss of 532 gigatons of ice – equivalent to about 66 tons of ice for every person on Earth – was 15% more than the previous record in 2012.
The ice melt from Greenland is of particular concern, as the old ice sheet contains enough water to raise sea levels by at least 6 meters (6 meters) when it melts away completely.
The study adds evidence that Greenland’s icy bulk is melting faster than expected amid global warming. Another study last week indicated that the island no longer received annual snowfall to replace ice lost after melting and chilling on the sides of glaciers.
“We are probably on the path to a faster sea level rise,” Sasgen told Reuters. “More melting of the ice sheet is not compensated by periods in which we have extreme snowfall.”
The study, published in the journal Communications Earth & Environment, used data collected by satellites to measure the gravity of the ice mass, which scientists can use to calculate how much snow and ice is trapped inside.
Other research has shown that melting is aided by water pooling above the ice and flowing through meltwater between the ice sheet and the subsurface.
These studies help scientists refine their projections on how climate change will affect the Arctic, and how quickly. Sasgen compared the sober process to getting annoying news from a doctor.
“It’s always depressing to see a new record,” Sasgen said.
But the studies provide insight into “where the problem is, and you also know to some extent what the treatment is,” Sasgen added.
“It’s hard to say if these (weather) patterns will be the new normal, and which pattern will occur at what frequency,” Sasgen said.
The Arctic has been warming at least twice as fast as the rest of the world over the past 30 years as the amount of greenhouse gases collected in the atmosphere continues to increase. That warming has also affected the ice in the Arctic Ocean, which shrank to its record low in 40 years in July.
As for the fate of Greenland, “I would argue that we’re a new normal of mass loss over the past few decades,” said Laura Andrews, a glaciologist at the NASA Goddard Space Flight Center not involved in the new study. “Greenland will continue to lose mass.”
If the rate of ice loss continues in 2019, the annual impact on sea levels could cause increasing coastal flooding affecting up to 30 million more people each year by the end of the century, said Andrew Shepherd, a polar scientist at the University of Leeds specializes in ice sheet observation. Shepherd was not involved in the new investigation.
The new findings underscore that “we need to prepare for an additional 10 centimeters (4 inches) global sea level rise with 2100 from Greenland alone,” Shepherd said. “We need to invent a new worst-case scenario for global warming, because Greenland is already following the current one.”
Report by Cassandra Garrison; Edited by Katy Daigle and Will Dunham
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