Greenland Ice Loss: 8,000 Tons/Second, Every Minute, Every Hour, Every Day - Far Worse Than Thought
New research reveals that within the Greenland ice sheet there is a recently formed layer of ice that has been found where it should not be. It is this ice layer that will cause even greater rates of sea level rise than had previously been thought. Greenland is a moist environment and until recently most surface meltwater would percolate into the tightly packed snow on the surface absorbing vast quantities of water. But the discovery of this new ice layer, which formed during a very warm melt season in 2012, shows that the massive ice sheet can no longer absorb meltwater in some areas.
John R. Platt has a must read piece in Take Part that summarizes the recent research titled “Greenland meltwater storage in firn limited by near-surface ice formation” that was recently published in the journal Nature. (Firn is defined by the Free Dictionary as “Granular, partially consolidated snow that has passed through one summer melt season but is not yet glacial ice. Also called old snow.”)
Colgan said the “lion’s share” of that loss—about 5,000 tons per second—comes in the form of meltwater. The ice sheet, like a sponge, used to be able to absorb most of what melted each year because the uppermost layers are composed of tightly packed but permeable snow, as opposed to the impermeable layers of ice much farther below. That porous surface, called “firn,” normally would allow meltwater to sink downward, where it would refreeze and stay within the glacier.
A well-respected group of scientists noted that the percolation of meltwater through the firn began to change about 10 years ago. It was hard not to note that massive meltwater rivers had formed on the ice sheet and the meltwater that did not descend to the bedrock via a moulin (a vertical conduit that channels water downwards) became rushing torrents to the sea from distances of up to 30 miles. The study’s authors note that rivers had always been a part of the hydrology of Greenland, but they only were known to have traveled 15 miles. One of the study authors, William Colgan of York University in Toronto, noted: “That led us to speculate that the downward motion was being blocked somehow.” It all stems from an extreme melt that took place in 2012. When that melted snow refroze, it formed a layer of ice several meters thick in the middle of the firn. Now melting water hits that thick ice layer and can sink no farther. Since it can’t go down, it goes sideways. “The rivers go downhill from the high interior of the ice sheet toward the coast,” Colgan said.
EDIT
http://www.dailykos.com/stories/2016/2/24/1488167/-Greenland-Ice-sheet-is-now-losing-about-8-000-tons-every-second-year-round-day-in-and-day-out
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The stupid, greedy DENIAL of reality by the Republican party is the great tragedy of our era.
Water can no longer penetrate, only run off.
Wonderful.
and bring in some nonsense about how gullible us dumb liberals are. 
I am saddened that I fear I wont live long enough to see deniers suffer the consequences of their asinine attitudes.
To be clear I wish no physical harm on them, only property damage. Maybe their flat screen on Super Bowl Sunday 