Greenland Ice Sheet apparently gains mass for the 2nd year in a row
Long-time WUWT reader Dave Burton writes:
I’ve seen no official pronouncement from DMI, but here are their graphs for Greenland Ice Sheet (GIS) surface mass balance (SMB), for the 2016-2017 glaciological year (Sept. 1 – Aug. 31), and for the 2017-2018 glaciological year. That’s the ice sheet mass balance before accounting for ice lost through glacier calving & submarine melting. (The fonts look a bit oddly stretched, because the two original graphs on the DMI site are scaled differently, and I resized them with IrfanView so that the two graphs would be the same size.)
DMI’s report on the 2016-2017 glaciological year says that,
“Greenland on average loses around 500 Gt of ice each year from calving and submarine melt processes. If we subtract this from our figure of 544 Gt for the SMB it would suggest Greenland gained a small amount of ice this year.”
From eyeballing the graph, it appears that the GIS ended this glaciological year (2017 – 2018) with a SMB of about +520 Gt. Subtracting 500 Gt for iceberg calving and submarine melt suggests a very small gain of about +20 Gt of ice.
That’s completely negligible with regards to global sea-level, since it takes 362 Gt of meltwater to raise the oceans by 1 millimeter. But if it were a loss of 20 Gt I’ll bet the press would report it as “22 cubic km of ice,” or “more than five cubic miles of ice,” or perhaps, “more than 8400 times the volume of the Great Pyramid of Giza.”
via Watts Up With That? https://ift.tt/1Viafi3