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Antarctica Is Losing Ice Faster Every Year (qz.com)
A survey of satellite data published in the journal Cryosphere confirms what scientists have suspected for a while now: ice loss from the critical region of Antarctica is happening at an increasingly fast pace. Quartz reports: In total, researchers found that Antarctica lost roughly 1,929 gigatons of ice in 2015, which amounts to an increase of roughly 36 gigatons per year every year since 2008. (A gigaton is one billion tons.) Nearly 90% of that increase in loss occurred in West Antarctica, "probably in response to ocean warming," according to NASA. The new data analysis mostly confirms other recent research, but does so with a higher degree of precision by using a new technique that can process a larger amount of satellite data than was possible before.
West Antarctica has been losing a lot of ice in recent years, and at an ever-growing pace, while East Antarctica is losing ice more steadily. The West Antarctic ice sheet is of particular concern because, like a building that stands on an uneven foundation, it is inherently unstable, making it especially vulnerable to the warming climate. If the entire ice sheet were destabilized and melted into the sea, researchers estimate it would lead to 3 meters (9 feet) of sea level rise globally. Models suggest that under a low-emissions scenario, where the world commits to "peaking" and then steadily reducing emissions in the near future, complete destabilization of the West Antarctic ice sheet is possible to avoid. But under medium- or high-emissions scenarios, the loss of the ice sheet becomes inevitable.
West Antarctica has been losing a lot of ice in recent years, and at an ever-growing pace, while East Antarctica is losing ice more steadily. The West Antarctic ice sheet is of particular concern because, like a building that stands on an uneven foundation, it is inherently unstable, making it especially vulnerable to the warming climate. If the entire ice sheet were destabilized and melted into the sea, researchers estimate it would lead to 3 meters (9 feet) of sea level rise globally. Models suggest that under a low-emissions scenario, where the world commits to "peaking" and then steadily reducing emissions in the near future, complete destabilization of the West Antarctic ice sheet is possible to avoid. But under medium- or high-emissions scenarios, the loss of the ice sheet becomes inevitable.
Even when the ice melt has destroyed cities, creating new borders for nations with lands near sea level, there will still be deniers claiming a population of 7 billion humans had nothing to do with it... despite the historic release of sequestered carbon associated with our species' selfish, expected level of comfort.
Happiness in intelligent people is the rarest thing I know.
Ernest Hemingway
And why would that be? Science isn't religion. Anyone with any sense will admit that they could be wrong.
World sea levels go up three meters? A quick computation shows that is "probably" very very wrong.
Kindly share your "quick computation." And explain why it disproves the conclusions of the paper linked in TFS.
If it weren't for deadlines, nothing would be late.
The article uses "probably", scientists use "likely".
FYI the word count in the PDF:
probably:0
likely:13
Likely has an actual meaning in scientific language, and it's not the same as general English.
What I cringe at is feckless assholes that use every excuse they can to suck wind through their teeth and suggest doubt where there is none.
Since when is one foot = 0.75 of a mile?
And a better approach would be the surface area of a sphere, 4 pi r ^ 2.
4 * pi * 6378 * 6378 = 500,000,000 km^2 according to my trusty slide rule.
Volume of 1 m coverage is 500,000,000,000,000 m^2 or 500,000 giga tonnes of water if I have not slipped a few zeros.
HiThere pointed out:
The thing is, it's questionable how much of the change is already committed. There are a lot of lags in various feedback cycles, and if, say, the permafrost methane is already inevitable, then that may mean that a much greater temperature rise is already inevitable. Methane may have a half life of 50 years (?? not that long??) but it's a much stronger greenhouse gas than CO2, and when it degrades, it degrades to CO2. Nobody's quite sure how much methane is locked up in the permafrost...but it's already starting to melt, so it may well be too late to stabilize things. How much mitigation we can do is uncertain. And the sun is now hotter than it was the last time all that CO2 was in the atmosphere (see carboniferous period http://www.ucmp.berkeley.edu/c...), so nobody's quite certain what will happen. There are models, but anyone who believes them needs their head examined.
FWIW, methane's half-life as an atmospheric gas is about 12 years - but, to your point, its effects on atmospheric warming persist for as long as a century. C02 hangs around for up to 50,000 years, so its effects on warming are more critical in the longer term. Other gases and aerosols also contribute to global warming (and thus climate change) to various degrees, and with varying amounts of persistence. It's a complex set of interactions.
What nobody seems to be taking into account is the rapidly-mounting evidence that glaciers and icecaps are complex, unstable systems, the continued existence of which depends on relative stability in base climate conditions (aka "chaotic systems"). Every year for the past decade, glaciologists studying the Greenland icecap have observed that melting there is proceeding - and increasing - far faster than their models predict. It's an asymptotic trend that leads to what I think is the inevitable conclusion that Greenland's ice sheet (which is three miles thick in the center) is going to collapse within no more than a few hundred years.
That's way, WAY faster than even recently-revised models predict - but those models are predicated on the notion that miles-thick icecaps are essentially reservoirs of cold that will preserve their integrity for millenia. The problem is that all the current evidence is that those assumptions are unwarranted. They certainly don't account for the staggering rate of surface melt, or for the destablilzing effect of all that meltwater eroding the integrity of the ice sheet beneath the surface as it drains, via moulins, all the way to bedrock.
The instability of the icecap surface (its so-called "rottenness") has led the government of Greenland to altogether ban scientists from setting foot on it during the warm season, for safety reasons. They're now forced to deploy and recover automated weather stations and other instrument packages from helicopters hovering above the ice, in order to comply with that prohibition. In fact, it's getting harder for glaciologists and climatologists to collect reliable, long-term, automated data from Greenland in general, because their instrument packages and weather stations keep disappearing into the moulins that unpredictably open underneath them.
The current climate change situation reeks to me of the Permian/Triassic catastrophe. That event was produced by natural causes (although exactly what triggered it initially is still not definitively settled) whereas this one was unquestionably precipitated by global carbon emissions resulting from the age of industrialization, particularly in the developed world.
We, as a species, can be forgiven for not realizing the consequences of causing such enormous increases in CO2 emissions back in the 19th century and the first ... let's be generous and say "eight
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