Ice loss from Antarctica has sextupled since the 1970s, new research finds

Chris Mooney is at his usual pulpit below making a muckle out of a mickle. He quotes some big numbers but fails to mention that the ice loss claimed is the tiniest fraction of the whole. Someone has calculated that at that rate of ice loss  the last ice will melt in the year 3079

But let us forget Mooney and look at the underlying journal article headed by that long-time warmist Eric Rignot. Abstract below Mooney's lucubrations.

It is a joke of an article.  It is heavily dependent on modelling and completely ignores the well-known influence of subsurface vulcanism in West Antarctica, including the peninsula. We have known about melting ice there for a long time.

The one innovation is that curly-haired Eric has implicated East Antarctica in the melting.  How confident we should be in that finding can be judged by Eric's own words on the matter in his conclusions: "we posit that a similar situation is taking place in Wilkes Land, where novel and sustained oceanographic data are critically needed." Sounds like the data he already has is pretty punk.

Antarctic glaciers have been melting at an accelerating pace over the past four decades thanks to an influx of warm ocean water — a startling new finding that researchers say could mean sea levels are poised to rise more quickly than predicted in coming decades.

The Antarctic lost 40 billion tons of melting ice to the ocean each year from 1979 to 1989. That figure rose to 252 billion tons lost per year beginning in 2009, according to a study published Monday in the Proceedings of the National Academy of Sciences. That means the region is losing six times as much ice as it was four decades ago, an unprecedented pace in the era of modern measurements. (It takes about 360 billion tons of ice to produce one millimeter of global sea-level rise.)


Four decades of Antarctic Ice Sheet mass balance from 1979–2017

Eric Rignot et al.


We use updated drainage inventory, ice thickness, and ice velocity data to calculate the grounding line ice discharge of 176 basins draining the Antarctic Ice Sheet from 1979 to 2017. We compare the results with a surface mass balance model to deduce the ice sheet mass balance. The total mass loss increased from 40 ± 9 Gt/y in 1979–1990 to 50 ± 14 Gt/y in 1989–2000, 166 ± 18 Gt/y in 1999–2009, and 252 ± 26 Gt/y in 2009–2017. In 2009–2017, the mass loss was dominated by the Amundsen/Bellingshausen Sea sectors, in West Antarctica (159 ± 8 Gt/y), Wilkes Land, in East Antarctica (51 ± 13 Gt/y), and West and Northeast Peninsula (42 ± 5 Gt/y). The contribution to sea-level rise from Antarctica averaged 3.6 ± 0.5 mm per decade with a cumulative 14.0 ± 2.0 mm since 1979, including 6.9 ± 0.6 mm from West Antarctica, 4.4 ± 0.9 mm from East Antarctica, and 2.5 ± 0.4 mm from the Peninsula (i.e., East Antarctica is a major participant in the mass loss). During the entire period, the mass loss concentrated in areas closest to warm, salty, subsurface, circumpolar deep water (CDW), that is, consistent with enhanced polar westerlies pushing CDW toward Antarctica to melt its floating ice shelves, destabilize the glaciers, and raise sea level.

PNAS published ahead of print January 14, 2019.">SOURCE

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