West Antarctic melt rate has tripled

December 2, 2014
UCI and NASA glaciologists, including Isabella Velicogna and Tyler Sutterley, have discovered that the melt rate of glaciers in West Antarctica has tripled, with the loss of a Mt. Everest's worth of water weight every two years.

A comprehensive, 21-year analysis of the fastest-melting region of Antarctica has found that the melt rate of glaciers there has tripled during the last decade.

The glaciers in the Amundsen Sea Embayment in West Antarctica are hemorrhaging ice faster than any other part of Antarctica and are the most significant Antarctic contributors to . This study is the first to evaluate and reconcile observations from four different measurement techniques to produce an authoritative estimate of the amount and the rate of loss over the last two decades.

"The mass loss of these glaciers is increasing at an amazing rate," said scientist Isabella Velicogna, jointly of the UC Irvine and NASA's Jet Propulsion Laboratory. Velicogna is a coauthor of a paper on the results, which has been accepted for Dec. 5 publication in the journal Geophysical Research Letters.

Lead author Tyler Sutterley, a UCI doctoral candidate, and his team did the analysis to verify that the melting in this part of Antarctica is shifting into high gear. "Previous studies had suggested that this region is starting to change very dramatically since the 1990s, and we wanted to see how all the different techniques compared," Sutterley said. "The remarkable agreement among the techniques gave us confidence that we are getting this right."

The researchers reconciled measurements of the mass balance of glaciers flowing into the Amundsen Sea Embayment. Mass balance is a measure of how much ice the glaciers gain and lose over time from accumulating or melting snow, discharges of ice as icebergs, and other causes. Measurements from all four techniques were available from 2003 to 2009. Combined, the four data sets span the years 1992 to 2013.

The glaciers in the embayment lost mass throughout the entire period. The researchers calculated two separate quantities: the total amount of loss, and the changes in the rate of loss.

The total amount of loss averaged 83 gigatons per year (91.5 billion U.S. tons). By comparison, Mt. Everest weighs about 161 gigatons, meaning the Antarctic lost a Mt.-Everest's-worth amount of water weight every two years over the last 21 years.

The rate of loss accelerated an average of 6.1 gigatons (6.7 billion U.S. tons) per year since 1992.

From 2003 to 2009, when all four observational techniques overlapped, the melt rate increased an average of 16.3 gigatons per year—almost three times the rate of increase for the full 21-year period. The total amount of loss was close to the average at 84 gigatons.

The four sets of observations include NASA's Gravity Recovery and Climate Experiment (GRACE) satellites, laser altimetry from NASA's Operation IceBridge airborne campaign and earlier ICESat satellite, radar altimetry from the European Space Agency's Envisat satellite, and mass budget analyses using radars and the University of Utrecht's Regional Atmospheric Climate Model.

The scientists noted that glacier and ice sheet behavior worldwide is by far the greatest uncertainty in predicting future sea level. "We have an excellent observing network now. It's critical that we maintain this network to continue monitoring the changes," Velicogna said, "because the changes are proceeding very fast."

Explore further: Image: Glaciers and mountains in West Antarctica

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aksdad
2.2 / 5 (11) Dec 02, 2014
glacier and ice sheet behavior worldwide is by far the greatest uncertainty in predicting future sea level

Here's a thought: predict future sea level from current sea level trends. It's a lot easier.

Any acceleration in glacier loss in Western Antarctica has had so small an effect on global sea levels that you can't find it. Sea level rise isn't accelerating. See for yourself:

http://sealevel.colorado.edu/

Maybe it's because some of that loss is mitigated by the growth of the much larger Eastern Antarctic ice sheet.
Water_Prophet
2.1 / 5 (7) Dec 02, 2014
@aksdad,
really, that's all they seem to be measuring. You are certainly one odd fish. I bet you've got all sorts of interesting perspectives.

Ones, I bet I don't want to know, but I'll already give 'em 10/10 for interesting.

So if we can believe this article, it answers that question we all wanted to know: If surface area was increasing, was volume/mass.

Looks like it wasn't. Well Deniers, not that they say much at all, but I don't see any loopholes, you?
Maggnus
4.4 / 5 (14) Dec 02, 2014
askdad, at it again I see.

A red herring. No, the WA icesheet, by itself, will have little effect on global sea level,. But, and here's the thing so try to pay attention: ALL of the ice on the planet, except for a very small possible area in East Antarctica, and a small area in the Himalayas, is melting. As is the permafrost in Northern NA and Asia.

I love how you post to a site that discusses the amount of sea level rise they continue to measure. It suggests that you do not understand what the graphs are saying, given your propensity for denying science. Would you like runrig to take some time and explain it to you?

Her is some light reading for you: http://academics....tain.pdf

You know, maybe spend a few minutes and look at what is happening to Florida. Right there, in dem thar United States.

nick_c
1.6 / 5 (14) Dec 02, 2014
The melt is not caused by Global Warming, If you checked under the ice sheets there are a number of active volcanoes cause the ice to melt. Fact!
Water_Prophet
2 / 5 (8) Dec 02, 2014
@nik_c
Decent call, except the volcanoes have always been there...
Except Mona Loa and other volcanoes are increasing in activity, so good call.
Maggnus
4.4 / 5 (14) Dec 02, 2014
The melt is not caused by Global Warming, If you checked under the ice sheets there are a number of active volcanoes cause the ice to melt. Fact!


No, not fact, fantasy. There are volcanoes there - but they have been there a very long time. They are no more responsible for the melting ice on Antarctica then volcanoes under the Arctic are responsible for permafrost melt.
runrig
5 / 5 (11) Dec 03, 2014
Sea level rise isn't accelerating. See for yourself:

http://sealevel.colorado.edu/

Look at the long term trend and and consider the reasons likely to cause short-term sea-level variation..... like the dip seen 2001/12 when Warm waters (la Nina effect) in the W Pacific caused considerable rainfall over NE Ozz. It reduced it.
try looking at this graph - and see that it took 60 yrs at the start to rise 2mm at the end it's taken 30.
http://en.wikiped...EPA).png
Scroofinator
1 / 5 (7) Dec 03, 2014
It just depends on who you want to believe: the $22 Billion a year industry that has lost it's predictive power, or the scientists who call them out?

http://www.spacea...rise.pdf
runrig
5 / 5 (10) Dec 03, 2014
It just depends on who you want to believe: the $22 Billion a year industry that has lost it's predictive power, or the scientists who call them out?

http://www.spacea...rise.pdf


From the above's website:
" Space and Science Research Corporation (SSRC) is a leading independent US climate research company. It is the foremost institution in the United States dedicated to communicating the need to prepare for the new cold climate epoch. "

Ahem:
Any climate "organisation" worth the name looks at climate FULL STOP. And not for a coming "new cold climate epoch."
Scroofinator
1 / 5 (6) Dec 03, 2014
Any climate "organisation" worth the name looks at climate FULL STOP. And not for a coming "new cold climate epoch."


They are looking at everything (especially the Sun), which is why they are predicting we are heading into a new 'Maunder Min'.

Poor attempt at discrediting the work they've done...
runrig
5 / 5 (10) Dec 03, 2014
Any climate "organisation" worth the name looks at climate FULL STOP. And not for a coming "new cold climate epoch."


They are looking at everything (especially the Sun), which is why they are predicting we are heading into a new 'Maunder Min'. Poor attempt at discrediting the work they've done


They discredit themselves, as if you read "about us" they are convinced that we are "going into a cold epoch". This against all consensus science (and what is known of the Sun).
As I said, science doesn't start out to prove a premise. No matter what you think.
BTW: I too think it probable that a Maunder min is on the cards by 2030 - but it only reduces solar insolation by what we have at the 11 yr cycle min, (well I think one study says it may have been 0.2%).
It will affect the Stratosphere re O3 chemisty and reduce warming locally there, in turn causing tropospheric wind regimes to change (mainly NH winters). 1364W/M^2 instead of 1366W/M^2 will not cause great cooling.
imido
Dec 03, 2014
This comment has been removed by a moderator.
Water_Prophet
2.5 / 5 (4) Dec 03, 2014
Imido, not to dis. your theory, but dark matter is just cold matter un-illuminated by suns. It is Jupiters and Saturns wandering the galaxy alone.
Matter, is after all matter, and is conserved. It can't just spontaneously "arrive" and impact the environs.
Scroofinator
1 / 5 (2) Dec 04, 2014
science doesn't start out to prove a premise

The premise was only established after accounting for the Sun's solar cycles and the influence on the climate. The GHG argument was investigated and deemed to be inadequate. Is that not the scientific method?
I too think it probable that a Maunder min is on the cards by 2030 - but it only reduces solar insolation by what we have at the 11 yr cycle min, (well I think one study says it may have been 0.2%).
It will affect the Stratosphere re O3 chemisty and reduce warming locally there, in turn causing tropospheric wind regimes to change (mainly NH winters). 1364W/M^2 instead of 1366W/M^2 will not cause great cooling.

If a reduction in TSI is all you believe happens during a solar min, then why did the Maunder Min cause such drastic cold for decades?
runrig
5 / 5 (8) Dec 04, 2014
If a reduction in TSI is all you believe happens during a solar min, then why did the Maunder Min cause such drastic cold for decade?

It wasn't "drastic" save for more frequent local cold winters in the NH and other normal "weather" events. Thermodynamics wins and you will need to lose quite a few Watts to fit the "drastic" category. The accepted theory is the change of tropospheric wind regime due low UV impinging O3 in the Strat and consequent shifted ocean currents when this regime becomes chronic. Coupled with a prolonged period of volcanic ejections.
http://www.nature...040.html

Scroofinator
not rated yet Dec 04, 2014
The accepted theory is the change of tropospheric wind regime due low UV impinging O3 in the Strat and consequent shifted ocean currents when this regime becomes chronic.

So you're saying that a .2% change in TSI can cause all this to happen? Then why does it not happen every 11-22 years?
Maggnus
5 / 5 (7) Dec 04, 2014
Decent call, except the volcanoes have always been there...
Except Mona Loa and other volcanoes are increasing in activity, so good call.
In my dark matter theory the global warming is mostly of geothermal origin and the undersea volcanoes (which are otherwise hidden) will contribute to it too. We even have http://phys.org/n...oss.html instead from surface.


Crock!!!
Maggnus
5 / 5 (8) Dec 04, 2014
It will affect the Stratosphere re O3 chemisty and reduce warming locally there, in turn causing tropospheric wind regimes to change (mainly NH winters). 1364W/M^2 instead of 1366W/M^2 will not cause great cooling.
Correct, and even less now. If there is a silver lining to global warming, it is that our ancestors in a few thousand years won't have to deal with an ice age. The big "if" there is, will there be any ancestors to not deal with it?
runrig
5 / 5 (8) Dec 04, 2014
The accepted theory is the change of tropospheric wind regime due low UV impinging O3 in the Strat and consequent shifted ocean currents when this regime becomes chronic.

So you're saying that a .2% change in TSI can cause all this to happen? Then why does it not happen every 11-22 years?

Yes, but it soon returns to a Max solar output. Also even in the LIA not every winter was severe in W Europe and the E USA. There has to be other factors in the equation. This year we have an E'ly QBO (Quasi-Biennial Oscillation) and the OSI (October snow advance index ) for Eurasia is the highest on record + a weak El Nino ... so it's odds on for a SSW (stratospheric sudden warming) into the new year. A disruption of the PV (Polar vortex). Any one of those things missing may mean nothing happening. It's a finely judged dance of cause -effect. This is weather. Delineated into Climate by prolonged effects such as the MM.
Scroofinator
1 / 5 (1) Dec 04, 2014
Yes, but it soon returns to a Max solar output

Then why aren't there oceanic current changes every 11-22 years?
runrig
5 / 5 (8) Dec 05, 2014
Yes, but it soon returns to a Max solar output

Then why aren't there oceanic current changes every 11-22 years?

For the reason I just stated, because the minimum bit of the cycle is only around 1 to 4 years and oceans will take a good bit longer than that to respond, and even if they did would return to normal. I can imagine a min that lasts ~100 yrs having an effect on currents and the primary effect will be seen in winter in the N Atlantic with a much more -ve NAO (low pressure near Iceland replaced by high) and so the Gulf Stream will not be forced up through the Norwegian sea.
Mike_Massen
4.4 / 5 (7) Dec 06, 2014
imido claimed
In my dark matter theory the global warming is mostly of geothermal origin and the undersea volcanoes (which are otherwise hidden) will contribute to it too.
1.Therefore you must claim geothermal has NOT already been accounted for, where is evidence for this ?
2. U worked out from your model heat in Joules & over what region ?
3. U accounted for glacial ice mass loss due to heat flow re 2.?
4. U factored in specific heat of water ?
5. Nuclear equation - which radionucleotides; K, Th, Cs, which species ?
6. Can u point to decay chain products re 5. & evidence ?

imido claimed
We even have direct evidence for this in warm circumpolar underwater currents, which erode the Antarctic ice from bottom up instead from surface.
Really, where ?
Any journals, not others comments u have referenced on other threads ?

Is your evidence really DIRECT - another claim ?

imido has this anything to do with your god that punished eve, is that why we have AGW ?
Mike_Massen
4.5 / 5 (8) Dec 06, 2014
Scroofinator asked
Then why aren't there oceanic current changes every 11-22 years?
Because & further to runrig's post, despite the solar minima/maxima insolation is remarkably stable, Eg

http://www.skepti...asic.gif

When you do the physics eg specific heat of water you discover the oceans have IMMENSE thermal inertia and due to the large specific heat ~4000x that of atmosphere that any even slight rise in ocean temps is an indication of large heat being absorbed & obviously if this trend continues oceans will be less habitable for some fish species and/or patterns will change this disrupts food sources from the oceans. Add to that decreased ocean salinity & increased acidification means we have a lot to deal with if we do want to have a sustained food source from the sea & allowing for higher sea levels also from coastal areas.

But, hey u already knew this didnt u re specific heat, r u the other who claimed a physics degree ?
OZGuy
5 / 5 (7) Dec 06, 2014
imido states "In my dark matter theory..."

A scientific theory is a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. Such fact-supported theories are not "guesses" but reliable accounts of the real world.

Does your dark matter theory stand up to that simple definition or is it merely an opinion/belief/fantasy? If it does then show us the evidence and once proven we'll all applaud, if not then stop pretending it's a scientific theory.

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