Study finds 24% of West Antarctic ice is now unstable

American Geophysical Union

WASHINGTON–In only 25 years, ocean melting has caused ice thinning to spread across West Antarctica so rapidly that a quarter of its glacier ice is now affected, according to a new study.

Scientists at the Centre for Polar Observation and Modelling (CPOM), based at the University of Leeds in the United Kingdom, have combined 25 years of European Space Agency satellite altimeter measurements and a model of Antarctica’s regional climate to track changes in snow and ice cover across the continent.

A new study in the AGU journal Geophysical Research Letters finds Antarctica’s ice sheet has thinned by up to 122 meters in places, with the most rapid changes occurring in West Antarctica where ocean melting has triggered glacier imbalance.

This means the affected glaciers are unstable as they are losing more mass through melting and iceberg calving than they are gaining through snowfall.

The research team found the pattern of glacier thinning has not been static over time. Since 1992, the thinning has spread across 24 percent of West Antarctica and over the majority of its largest ice streams – the Pine Island and Thwaites Glaciers – which are now losing ice five times faster than they were at the start of the survey.

The study used over 800 million measurements of the Antarctic ice sheet height recorded by the ERS-1, ERS-2, Envisat, and CryoSat-2 satellite altimeter missions between 1992 and 2017 and simulations of snowfall over the same period produced by the RACMO regional climate model.

Together, these measurements allow changes in the ice sheet height to be separated into those due to weather patterns, such as less snowfall, and those due to longer term changes in climate, such as increasing ocean temperatures that eat away ice.

“In parts of Antarctica, the ice sheet has thinned by extraordinary amounts, and so we set out to show how much was due to changes in climate and how much was due to weather,” said Andy Shepherd, a polar scientist at the University of Leeds, director of CPOM and lead author of the new study.

To do this, the team compared the measured surface height change to the simulated changes in snowfall, and where the discrepancy was greater they attributed its origin to glacier imbalance.

They found that fluctuations in snowfall tend to drive small changes in height over large areas for a few years at a time, but the most pronounced changes in ice thickness are signals of glacier imbalance that have persisted for decades.

“Knowing how much snow has fallen has really helped us to detect the underlying change in glacier ice within the satellite record,” Shepherd said. “We can see clearly now that a wave of thinning has spread rapidly across some of Antarctica’s most vulnerable glaciers, and their losses are driving up sea levels around the planet.

Altogether, ice losses from East and West Antarctica have contributed 4.6 millimeters to global sea level rise since 1992, according to the study.

“This is an important demonstration of how satellite missions can help us to understand how our planet is changing,” said Marcus Engdahl, an Earth observation scientist at the European Space Agency and co-author of the new study. “The polar regions are hostile environments and are extremely difficult to access from the ground. Because of this, the view from space is an essential tool for tracking the effects of climate change.”

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Notes for Journalists

This paper is freely available through June 30. Journalists and public information officers (PIOs) can download a PDF copy of the article by clicking on this link:

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2019GL082182

Multimedia accompanying this press release can be downloaded at the following link:

https://aguorg.sharepoint.com/:f:/s/newsroom/Ev-FolVlRCRDsTHyaiAYaWgB4WEqqohtr7J7qBCHuivzSA?e=ae7GbI

Journalists and PIOs may also request a copy of the final paper by emailing Lauren Lipuma at llipuma@agu.org. Please provide your name, the name of your publication, and your phone number.

Neither this paper nor this press release is under embargo.

Paper Title

“Trends in Antarctic Ice Sheet Elevation and Mass”

Authors

Andrew Shepherd: Centre of Polar Observation and Modeling, School of Earth and Environment, University of Leeds, United Kingdom;

Lin Gilbert: Mullard Space Science Laboratory, Department of Space & Climate Physics, University College London, United Kingdom;

Alan S. Muir: Mullard Space Science Laboratory, Department of Space & Climate Physics, University College London, UK; and Centre for Polar Observation and Modeling, Department of Earth Sciences, University College London, United Kingdom;

Hannes Konrad, Malcolm McMillan, Thomas Slater, Kate H. Briggs, Aud V. Sundal, Anna E. Hogg: Centre of Polar Observation and Modeling, School of Earth and Environment, University of Leeds, United Kingdom;

Marcus Engdahl: ESA-ESRIN, Rome, Italy.

From EurekAlert!

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131 thoughts on “Study finds 24% of West Antarctic ice is now unstable

  1. A quick scan of the paper shows not even a single mention of volcanoes or vulcanism.

    Also, from what I remember from ERS-1 and ERS-2, their data would not seem to support the notions expressed in the paper.

    ===|==============/ Keith DeHavelle (@DeHavelle)

    • Yep. The volcano activity has been known for a long time.

      Some 30 years ago, a scientist at the University of Colorado Denver suggested that heat from a mantle plume under Marie Byrd Land might explain regional volcanic activity and a topographic dome feature. Very recent seismic imaging has supported this concept. When Hélène Seroussi of NASA’s Jet Propulsion Laboratory in Pasadena, California, first heard the idea, however, “I thought it was crazy,” she said. “I didn’t see how we could have that amount of heat and still have ice on top of it.WUWT

      Academics show a remarkable ability to not know things that everybody else seems to know.

    • From here: Evidence of an active volcanic heat source beneath the Pine Island Glacier https://www.nature.com/articles/s41467-018-04421-3

      “Despite the accumulation of evidence, definitive proof of contemporary subglacial volcanism in West Antarctica is still missing.”

      “This excess heat is small compared to the heat content of Circumpolar Deep Water (ca. 12 kJ kg−1), demonstrating that volcanic heat does not contribute significantly to the glacial melt observed in the ocean at the front of the ice shelf. ”

      I don’t think volcanoes are to blame.

      • There are several recent papers that indicate geothermal activity IS having an effect on the glaciers/ice sheet. They just never say how much. The frustration I feel is that no one tries to quantify the loss from this source compared to that from ocean waters. If their analysis is that X% is from geothermal and it’s a very minor actor, fine. But no attribution study has been done as far as I know. We are left guessing.
        I would also like to see a paper that shows the increase in OHC from 50 years ago to today at the specific location of the glaciers/ocean interface. Saying that global oceans have warmed by some amount doesn’t cut it. Again, no quantification in how much warmer the waters have become to create this loss. It’s usually just a reference to “warm” water rather than warmer by X degrees.

        Let’s see if the new IPCC even mentions geothermal as a potential source of thinning. I couldn’t find any reference to it in AR5.

      • The survey that mapped heat fluxes beneath Antarctica took 50 years. Volcanism is known to vary, so no one can definitively say what the fluxes are now. Plus those values are modeled and not directly measured as ocean current temps are, thus bringing their quantitative accuracy into question.

      • If a trace gas can be blamed for global temperature rise, I would think that a well placed source of Geothermal heat might be able to take the blame for a Glacial melt.

        It might not be enough heat to explain all the heat but it maybe a catalyst for the rest.

      • How to lie with statistics 101.

        Compare the heat generated in one, small area with the heat content of the entire Circumpolar Deep Water circulation.

        Nobody has ever claimed that these volcanoes are heating all of the water around Antarctica, heck the volcanoes aren’t even in the ocean.
        The claim is that the volcanoes under the ice, are melting the ice. Trying to claim that they aren’t big enough to warm all the waters around Antarctica irrelevant nonsense.

        • But they might affect the sub-glacial lubrication, affecting the stop-start nature of glacial flow.

          However, my understanding is that nothing at all is seriously affecting the actual melting of Antarctic ice.
          Ignoring the isostatic adjustment, which is often described as the biggest single unknown for the mass balance, and the fact that they ‘modeled’ the precipitation, the known erratic nature of glacial flows suggests that these authors are talking out of their puckered anus-holes. They just don’t know. Not even close to knowing. Trading on ignorance and large error bars.

          So, nothing new in the world of global-warming alarmism.

          • Yeah right, 120+ meters of thinning directly observed and you are worrying about “adjustments”.

          • Claimed 120 meters. First off check the validity of the means of measurement, then show that there is anything unusual about the changes that remain.

    • Not to mention the use of unvalidated (invalid?) computer models for half of their argument.

    • Lame results, in my view. Ignoring subterranean active vulcanism by these guys was the first thing I noticed, too. But then, if you’re trying to prove a point (and want more money), you ignore unwanted data as an inconvenient truth.

    • I was thinking the exact same thing. Funny how those volcanoes are always conveniently forgotten.

  2. The imminent collapse of the West Antarctic ice cap was a scare campaign when I was a child 50 years ago. Yawn-still waiting. This sort of chicken little stuff has been going on for decades. What remains the same is that the “cause” is still us. The “cure” is to hand over lots and lots of money.

    • Since then we’ve moved a lot closer to collapse you mention. When the grounding line retreats enough WAIS is toast.

      [??? .mod]

  3. “and their losses are driving up sea levels around the planet.”

    Really? Where? It must show as an acceleration of SLR if this were indeed true.

    Why do they think it is necessary to make such BS statements that can easily be proven wrong?
    Is it an unthinking need to genuflect to the alarmism rhetoric of CC, to show everyone in their sphere of influence that they are true believers in the scriptures?

    Then there is this:
    ““This is an important demonstration of how satellite missions can help us to understand how our planet is changing,” said Marcus Engdahl, an Earth observation scientist at the European Space Agency and co-author of the new study. “The polar regions are hostile environments and are extremely difficult to access from the ground. Because of this, the view from space is an essential tool for tracking the effects of climate change.”

    Translation:
    1. We hate the cold. We’d rather stay in jolly old England and drink at the local pub every night.
    2. We can’t afford to actually go there and record this ice sheet-glacier stuff with hard DGPS survey measurements. That’s really hard work. And it might not show us what we believe is happening.
    3. We’d rather just download satellite altimeter data from somewhere else, and run it through our computer models and number mashers. Then we’ll adjust it till we get the answer our grant masters want to see.
    4. Now please, show us the money. We’re thirsty and want to head off to the pub now.
    – The state of Climate Science in 2019.

    • In situ and airborne observations absolutely also show that WAIS is getting unstable.

      • What is “getting unstable”?

        We’re in an interglacial. You could make that valid claim for almost every glacier/ice sheet around the world for the past 18,000 years.
        The burden of evidence is on the claimant.

        Is it due to anthropogenic climate change? Or simply changine climate?

        • You must be old school scientist. Modern version is find a surrogate like AOC or Algore to run around browbeating everyone. Only requirements are medium IQ and no sense of shame.

          For grins, check out mini-AOC on youtube

    • “Why do they think it is necessary to make such BS statements that can easily be proven wrong?”

      I don’t know why they make such statements, but the bad part about it is there are a lot of people who don’t have the ability or expertise to put this in perspective. Unless they read something like WUWT where the weaknesses in the arguments are put on display by other experts.

      WUWT is invaluable for debunking the CAGW arguments, or at least putting the arguments in perspective.

      • Simple – the lie gets around the world before the truth gets its pants on.

        The truth doesn’t get reported.

        They do it because the CAN.

  4. Altogether, ice losses from East and West Antarctica have contributed 4.6 millimeters to global sea level rise since 1992, according to the study.

    That’s 0,17 mm/p.a. unless I am very much mistaken. Why does this not worry my at all? Mother Nature at work!

    • Well, as always, they go for effect and massage even their own statements made elsewhere in the article.

      “..Antarctica has contributed 4.6 +- 1.2 mm to global sea rise.”

      An honest, non-alarming, scientist would have stated in the headline then that 3.4 mm (4.6 – 1.2 min error bound) over 27 years and actually reported a number of 0.13 mm / yr as compared to the current average annual sea level rise (Goddard chart) of around 3.4 mm/yr, which is around 3% and well within the error bars of global sea level measurement capability.

      However, if you take a look at how their get their error estimate, that section is full of estimates upon estimates of combined data sets with interpolated areas, etc, etc, etc built from one model modelling another model, etc, etc, etc. Give this to Steve McIntyre and watch him rip it apart.

      It would seem that we are either talking about not honest scientists or not competent ones, but what the hell I am saying, this is AGW so neither truth nor competence matter.

      • Three largely independent methods from space plus in situ and airborne data confirms this is actually happening. Steve McIntyre can stay home.

        • Please let us know where to find such databases necessary to draw these conclusions.

        • Oh please. One error does not cancel another and boy are there errors. Using gravity measurements to predict ice mass loss is a highly accurate endeavor? Cryosat 2 was launched in 2010, so I guess it was a time machine and could measure back to 1992? Ice sat (laser) from 2003 to 2009. ERS1&2, envisat, etc, etc. So, yes, 800 million samples from multiple sources over various ages of their life.

          Combine all these data using various models of the ice balance along with (what we all know wink wink) are always accurate climate models.

          Throw a few bristlecone pines, some frog legs, and finally goblin eggs into the cauldron and we can have a real witch’s brew. How accurate is it all? What that is the real magic isn’t it?

          • I have huge doubts regarding the claim that we can measure the height of a satellite to a few millimeters.

          • Ok, using gravity measurements to predict ice mass changes has been bothering me for a long time. It is known that there are mulitple active volcanoes under the Antarctic, which implies subterranean flows of magma. How can they distiguish minute gravitational changes caused by the outflow of water (ice melting), versus minute gravitational change caused by outflows of magma? If magma is flowing from under WAIS and pooling under the main continent, wouldn’t this produce the same localized gravitational changes as the WAIS losing ice mass?

    • I get 1.8mm, near enough. So that is 10% of the rise in the long term average rate, and about 5% of the highest short term average rate. One twentieth.

      Obviously melting of the Western Ice is not the major source of seal level rise.

      I note that they do not claim the water in the Southern Ocean is warming, nor that the air is warming, “driving” this melting. The steady expansion of sea ice over the same period contradicts, at least conceptually.

      The precipitation model must have some uncertainty. What is it expressed in %? Is that uncertainty larger, or several times larger, than the net ice mass loss they are claiming to model?

      The total precipitation must have some order of magnitude. If the uncertainty is expressed in %, such as 5%, what is that absolute uncertainty in terms of total mass balance? Expressed in terms of sea level, [mm/year], what is the volume uncertainty translated into these units?

      The unexpected result from this work is that it contradicts the total mass of ice calculation which has been based on the same satellite measurements. It is claiming a net loss of ice mass in Antarctica, right? That is obvious in the claims because they have given us a sea level rise value.

      Let us suppose it is approximately true that the mass was dropping from 1992-2012, and now it is growing again. What impact will this have on their conclusions? After all, the total ice mass is presently increasing. If their modelled precipitation doesn’t roughly match the past 10 years of data, “Huston” has a problem.

      Maybe the message of the paper is tied to the meaning of “unstable”, defined as “changing, therefore scary”. Given that we are being presented with different ice mass estimates rooted in the same source data, it seems that “the message” is also unstable. I find this science unsettling.

    • Most alarmists are far beyond being unstable, they have had their tipping point a long time ago…

      • Ve2 had it correct. climate scientist != climate alarmist. While the 97% of climate scientists make up part of the larger body of climate alarmists, 3% of climate scientists are not climate alarmists and there are many climate alarmists who are not climate scientists.

    • If you carry a small retractable tape measure with millimeters and inches on it, you can easily show any Greenbeaner or CAGWer or Climate Alarmian exactly what a 3.4mm rise amounts to.

      Spread over the surface of a planet that is mostly water with a small amount of land space, the “rise” amounts to:
      a) nothing
      b) nearly nothing
      c) mostly hot air from cash-hungry researchers and attention-seeking news critters
      d) all of the above

        • Sea level rise is accelerating and is currently 3+ m per millennium. Before industrial era the sea-level was much more stable than that for millennia.

          [?? .mod]

          • I don’t have the references here but we know from paleo-studies that the sea-level was remarkably stable for millennia. The rise started in the 19th century and is currently accelerating.

          • Every study I’ve ever seen shows that the rate of sea level rise has been constant since the end of the little ice age, over 150 years ago.
            During the little ice age, sea levels fell.

          • My God, that’s 3km every million years. No wonder mammals had to evolve on land a few of million years ago, there were no oceans around to live in yet.

            I have no idea where you see an acceleration in the chart provide by David, but that “curve” has been linear for some time now. Your sea front property will be there for some time yet, but if you are worried then I’ll take those worries from you at 5 cents on the dollar.

          • Joe, find us tide gauges (say 5) that show an acceleration in sea level rise. If you can’t, then admit that either you are lying or your source is lying.

          • Currently, the sea level rise is 0 over the last 3 yrs, as indicated by David’s graph from JPL et al.

          • There are raised beaches in Sri Lanka that are 8 to 10 metres above present sea level. You can clearly see them on Google Earth in the northeast part of the country. They are presumed to have formed during the Holocene Optimum about 7,000 to 6,000 years ago:
            https://www.jstor.org/stable/3060299

            Sri Lanka was not affected by glaciation and there is no isostatic rebound assumed to have taken place there (unlike the raised beaches in northern countries, which are mainly the result of isostasy)

            “Stable for millenia” – what serious publication do you get that from?

            Note on terminology: we are no longer supposed to use the term “Holocene (Climatic) Optimum” because “optimum” implies that it was “the best climate”. Now it’s the Holocene (Climatic) Maximum because warmer climate must, by definition, be a BAD THING. Of course, we don’t see it much in climate science literature at all because it was before industry and fossil fuels, so the fact that global climate was a couple of degrees warmer than now must have been due to – oh no! – natural causes.

            I stumbled across this while looking at the glacial-era land bridge between India and Sri Lanka. It’s very shallow water now and there are a series of sand bars, possibly anchored on coral reefs that are at semi-regular intervals along the 20-km long ridge across the Palk Strait. On an earlier, low-resolution version of Google Earth satellite imagery that was taken at high tide, they looked rectangular, and this gave rise to weird theories that they were man-made structures supporting a bridge. Current satellite imagery, probably taken at low tide when they are exposed, clearly shows that they are sand bars, but the tidal currents are so strong through there that you have to suspect buried coral reefs holding them in place.

            Doing a search for “Adam’s Bridge” will suck you into a fantasy world of Hindu legends and unfettered speculation about what they really mean, an interesting way to spend an evening. But I do like the idea that the legend of Lord Rama might hide a real historical reference to encounters between humans and the last Neanderthals.

          • Which paleo studies are you talking about?
            Are you familiar with the problem of resolution?
            Are you capable of understanding what the problem is with trying to compare a study with a resolution of 100 to 1000 years, with yearly data?

        • The 2mm pearl also shows the relative size of a climate alarmist’s intellect, compared to that of a rational intellect, indicated by the 9mm pearl [maybe that’s being too generous].

        • The problem is satellite measurement of ocean level has been adjusted to show acceleration.

          As noted below in a Nature published study (see link below) using mass balance (high estimate of ice melting) and thermal expansion (high estimate of temperature change) is less than 1.2 mm/year.

          There is a controversy to get to 1.2 mm/yr. 3.2 mm/yr is fantasy. Tide gauges show an observed sea level rise of 1.5 to 2.0 mm/year, as compared to the satellite after adjustments rate of rise of 3.2 mm/yr.

          https://wattsupwiththat.com/2018/02/04/the-fantasy-of-accelerating-sea-level-rise-just-got-hosed/

          The fantasy of accelerating sea level rise just got hosed

          https://notrickszone.com/2018/02/02/bewildered-scientists-a-global-warming-crisis-fails-to-appear-sea-level-rise-grinds-to-a-crawl/

          Only 1.5 mm/year
          Worse, satellite data measuring sea level have turned out to be far more complex and uncertain than one would wish, and evidence is piling up and showing that satellite data likely have been overstating sea level rise.

          For example when measuring sea level rise along coastlines (where people actually live) using tide gauges, the rise has even been far slower. Renowned Swedish sea level expert Axel Mörner published a paper in 2017 showing an observed sea level rise rate of only 1.5 – 2.0 mm/year.

          Second half of the 20th century slower than in the first half
          In another newly published paper by Frederiske et al. 2018 just this year, oceanographers estimate that global sea levels rose at a rate of only 1.42 mm per year between 1958 and 2014.

          That figure closely coincides with the results of Dr. Simon Holgate from 2007. According to the Holgate study: “The rate of sea level change was found to be larger in the early part of last century (2.03 ± 0.35 mm/yr 1904–1953), in comparison with the latter part (1.45 ± 0.34 mm/yr 1954–2003).”

          The Holgate result was confirmed by another 2008 paper authored by Jevrejeva et al, which found the fastest sea level rise during the past 300 years was observed between 1920 – 1950 with maximum of 2.5 mm/yr.

          In other words: global sea level rise has decelerated since the 1950s.

          At less than 2 mm annually, sea level is rising at only one sixth of the 12 mm per year rate projected by the PIK in 2013.

          Estimates of the volume increase due to ocean warming give a rate of about 0.5mmyr21 (ref. 8) and the rate due to mass increase, primarily from the melting of continental ice, is thought to be even smaller.

          https://iri.columbia.edu/~goddard/EESC_W4400/CC/miller_douglas_2004.pdf

          Mass and volume contributions to twentieth-century global sea level rise

          The rate of twentieth-century global sea level rise and its causes are the subjects of intense controversy1–7. Most direct estimates from tide gauges give 1.5–2.0mmyr21, whereas indirect estimates based on the two processes responsible for global sea level rise, namely mass and volume change, fall far below this range.

          Estimates of the volume increase due to ocean warming give a rate of about 0.5mmyr21 (ref. 8) and the rate due to mass
          increase, primarily from the melting of continental ice, is thought to be even smaller.

          Therefore, either the tide gauge estimates are too high, as has been suggested recently6, or one (or both) of the mass and volume estimates is too low. Here we present an analysis of sea level measurements at tide gauges combined with observations of temperature and salinity in the Pacific and Atlantic oceans close to the gauges.

          We find that gauge-determined rates of sea level rise, which encompass both mass and volume changes, are two to three times higher than the rates due to volume change derived from temperature and salinity data. Our analysis supports earlier studies that put the twentieth-century rate in the 1.5–2.0mmyr21 range, but more importantly it suggests that mass increase plays a larger role than ocean warming in twentieth-century global sea level rise.

          • “The fantasy of accelerating sea level rise just got hosed”

            No it didn’t ….

            https://www.earth-syst-sci-data.net/10/1551/2018/essd-10-1551-2018.pdf

            “We present estimates of the altimetry-based global mean sea level (average rate of 3.1 ± 0.3 mm yr−1 and acceleration of 0.1 mm yr−2 over 1993–present), as well as of the different components of the sea-level bud- get (http://doi.org/10.17882/54854, last access: 22 August 2018). We further examine closure of the sea-level budget, comparing the observed global mean sea level with the sum of components. Ocean thermal expansion, glaciers, Greenland and Antarctica contribute 42 %, 21 %, 15 % and 8 % to the global mean sea level over the 1993–present period. We also study the sea-level budget over 2005–present, using GRACE-based ocean mass es- timates instead of the sum of individual mass components. Our results demonstrate that the global mean sea level can be closed to within 0.3 mm yr−1 (1σ ). Substantial uncertainty remains for the land water storage component, as shown when examining individual mass contributions to sea level.”

      • Sara — Don’t need a tape measure. 3mm is almost exactly the thickness of two US (1.52mm) or Canadian(1.45mm) one cent coins.

  5. “The research team found the pattern of glacier thinning has not been static over time. ”

    Or I guess thickening. But we should only look at the last 25 years because that’s all we have data for.

    • What amazes me is why any one would think that “the pattern of thinning” of glaciers are/or should be static.
      Did someone not give them the note we are in an interglacial period?
      These PhDs should petition their schools for a tuition refund.

      • And then of course the altimeter accuracy – ERS1 & 2 -10cm,
        Envisat instrument error 2.4cm, orbit 3cm,
        Cryosat 2 -6cm

        • I’ll check with some colleagues who were on those projects, but if I recall the real accuracies were worse than that. It’s a hell of a feat to get absolute satellite position down to a few cm today, 20 years ago was not easier….

          Unfortunately AGW scientists think if you keep measuring different things with different tools over long periods of time then you can isolate one variable and make the errors go towards zero.

          • +1000

            Does anyone ever discuss this with these scientists? Are they ignorant of the subject of metrology?

            After seeing these wrong assumptions year after year after year, one must question the curriculum used to become a “climate scientist”.

        • Exactly. Central Limit Theorem is horribly abused by “Climate Scientists.” How were these measurements from low Earth orbit calibrated, exactly? Oh, they actually were NEVER calibrated? Funny how these “Scientists” never mention that.

          Wouldn’t have flown, not at my school…

        • Are the solid Earth tides being accounted for in their data reduction. The solid Earth tides are between 6 and 8 inches. This means that the satellites change altitude also with respect to the surface.

    • How do we know it isn’t cyclic? These climate ‘scientists’ simply chose the two most convenient years to justify their warming mantra.

      • Well yes it is cyclic, if the planet warms enough WAIS will disappear…we are heading that way.

        • At this moment Earth is heading in the general direction of Sagitarius. In 6 months, it will be heading away from Sagitarius. Earths cyclic (orbital) movement will never get us to Sagitarius.

          When was the last time WAIS disappeared? By agreeing that variation is cyclic, you have agreed that there is a limit to variation in any particular direction.

          SR

        • if you measured the temperature outside your house from 6 am to noon you apparently would assume you would be dead by midnight … you would be wrong just like you are wrong about “we are headed that way” but being wrong is the norm for you alarmists …

  6. Was there any mention about the volcanos which pass under this part of the Antarctic, on their way from South America to Mt.Erebus by the South Pole ?

    One would expect some local warming of the water around this part, but that
    does not mean a general waring of all the Oceans and Seas.

    I note the word Modelling as part of the title of this organization, what about
    some on the ground Observations.

    MJE VK5ELL

  7. Antarctica has been covered in ice for 15 million years.

    A scientist a study lasting just 25 years shows “extraordinary” changes.

    Let’s assume this scientist lives 80 years. If I study him for 1/600,000th of his life, or about four days, would I be able to say those four days are extraordinarily different from the other days in his life?

    • Chip: “Let’s assume this scientist lives 80 years. If I study him for 1/600,000th of his life, or about four days, would I be able to say those four days are extraordinarily different from the other days in his life?”

      Nice, except my quick check came up with about an hour of his life.

      Now if you happen to catch him while his hair is on fire, then yes, I’d say it was extraordinarily different from the rest of his life. Then again, I grew up with a guy so accident prone that a hair-on-fire incident would have been nothing unusual in the string of calamities that struck my buddy. Yet like the ice shelf, he’s still around despite his unending string of accidents.

  8. To do this, the team compared the measured surface height change to the simulated changes in snowfall, and where the discrepancy was greater they attributed its origin to glacier imbalance.“. Did they consider the possibility that the discrepancy was an error in the snowfall simulation?

  9. In 27 years they speculate a contribution to rising sea level of 0.18 inches. Wonder what the range of error might be?

  10. SO:
    “Founded in 1919, AGU is a not-for-profit scientific society dedicated to advancing Earth and space science for the benefit of humanity. We support 60,000 members, who reside in 135 countries, as well as our broader community, through high-quality scholarly publications, dynamic meetings, our dedication to science policy and science communications”

    I don’t see anywhere what percentage of the total Icecap of Antarctica this is..???
    Maybe they have it in the Paper, but I don’t see it here.
    And what percentage of the West Antarctic ice is compared to the whole of Antarctica ice cap???

    So the above quote looks like a consensus……just sayin.

  11. I’m not going to even try to worry about this. The climate has been warmer than at present many times in the past and there is no evidence of there having been a catastrophic change in the behaviour of the Antarctic ice sheet as a result. Why should we particularly worry about it it now?

    Having said that, there have been several mysterious oceanic high stands in the past for which there has been no explanation. It may be that there have been major collapses of Antarctic ice sheets from time to time but, as above, but the sea levels have recovered and no evidence of permanent change remains.

    • Eric, in warmer climates WAIS and the Greenland ice sheets have been considerably smaller. Therefore multi-metre sea level rise is to be expected.

      • It’s been warmer than it is today form 90 to 95% of the last 10K years, yet the catastrophes that haunt your fantasies never occurred.

  12. Take a look at Antarctica at NuSchool Earth, that area is currently -30C and the sea/air area around it is also way below zero at -7C to -10C.

  13. Right, so the oceans have risen by 0.007 inches/year during the study.
    How will I ever sleep again?
    I applaud their dedication.
    It takes a lot of effort to measure the oceans to that precision, I wonder if it is accurate?

    • Just as accurate as values of global average temperatures during the 19th century through early 20th century when there were no thermometers in 90-95% of the world.

  14. It is interesting to note that while any possible effect of geothermal heat on the WAIS is carefully avoided in this and other papers, the same effect is loudly proclaimed to have great influence on the Greenland Ice sheet (despite the absence of any active volcanoes). Google “Greenland hot-spot melting” for a nice collection of alarmist stories.

    Reason: the Greenland ice sheet cannot possibly collapse for topographic reasons so some other bugbear is needed there.

    By the way if a thinning glacier is automatically considered unstable there are probably no stable glaciers anywhere. It is extremely rare for a glacier to be in perfect balance and neither thickening or thinning.

  15. Best to look at the Antarctic as a whole and not a section-

    “NASA Study: Mass Gains of Antarctic Ice Sheet Greater than Losses”

    • You are correct. Interesting.

      “Mass gains of Antarctic ice sheet greater than losses”

      “According to the new analysis of satellite data, the Antarctic ice sheet showed a net gain of 112 billion tons of ice a year from 1992 to 2001. That net gain slowed to 82 billion tons of ice per year between 2003 and 2008.”

      https://climate.nasa.gov/news/2361/study-mass-gains-of-antarctic-ice-sheet-greater-than-losses/

      “Study: Mass gains of Antarctic ice sheet greater than losses

      A new NASA study says that an increase in Antarctic snow accumulation that began 10,000 years ago is currently adding enough ice to the continent to outweigh the increased losses from its thinning glaciers.
      The research challenges the conclusions of other studies, including the Intergovernmental Panel on Climate Change’s (IPCC) 2013 report, which says that Antarctica is overall losing land ice.

      According to the new analysis of satellite data, the Antarctic ice sheet showed a net gain of 112 billion tons of ice a year from 1992 to 2001. That net gain slowed to 82 billion tons of ice per year between 2003 and 2008.

      We’re essentially in agreement with other studies that show an increase in ice discharge in the Antarctic Peninsula and the Thwaites and Pine Island region of West Antarctica,” said Jay Zwally, a glaciologist with NASA Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study, which was published on Oct. 30 in the Journal of Glaciology.

      “Our main disagreement is for East Antarctica and the interior of West Antarctica – there, we see an ice gain that exceeds the losses in the other areas.” Zwally added that his team “measured small height changes over large areas, as well as the large changes observed over smaller areas.”

  16. “Antarctica’s ice sheet has thinned by up to 122 meters in places, with the most rapid changes occurring in West Antarctica <b.where ocean melting has triggered glacier imbalance.”

    Pure assumption. Field work hasn’t determined yet what effect melt water from volcanic heat has on thinning the ice cap and the ice sheet where rivers meet the ocean. The hundreds (possibly thousands) of massive lakes beneath the ice cap can only have been caused by ground heat, and that water has to flow to sea where topography allows.

    • The 8 meters for West Antarctica is way too high. It does not take into account that much of the ice is below sea level and if melted most of the water will be needed to fill out this space up to sea level. A realistic figure is about 3 meters.

  17. WHOA!!!

    4.6 mm in 27 years! I better run out and get some hip waders and a dinghy. You never know when quantum effects will combine with what’s already there to produce a sudden, catastrophic flood of the beaches!

  18. “This is an important demonstration of how satellite missions can help us to understand how our planet is changing”

    Except for the satellites that give us the wrong answer. Those are in error. Right?

    Andrew

  19. Ignore the HOT volcanos and plume behind the curtain…err, under West Antarctica’s ice.

  20. The NASA actually found that the Antarctic is gaining ice mass and contributes to a decrease of the sea level.

    Another pathetic BS from EurekAlert.

    • Not only NASA, a paper by Frezzotti et al 2011 also found Antarctica was gaining ice using actual ground measurements.

      https://www.the-cryosphere.net/7/303/2013/tc-7-303-2013.pdf

      “The temporal and spatial variability of the
      SMB over the previous 800 yr indicates that SMB changes
      over most of Antarctica are statistically negligible and do not
      exhibit an overall clear trend. This result is in accordance
      with the results presented by Monaghan et al. (2006), which
      demonstrate statistically insignificant changes in the SMB
      over the past 50 yr.”

      Note Figure 5. shows Antarctica currently has above average ice compared to the last 800 years.

      Actual ground measurements vs. “estimates” corrected to get the “right” answer. Any real scientists would have calibrated the satellite data against these real measurements. Yeah, right.

  21. “To do this, the team compared the measured surface height change to the simulated changes in snowfall, and where the discrepancy was greater they attributed its origin to glacier imbalance.”

    Oh wow, the stupid, it’s getting worse that we thought.

    • I couldn’t find where they validated the simulated snowfall to the actual snowfall. How can they assume that the simulated snowfall accurately followed the real thing?

  22. “and their losses are driving up sea levels around the planet.”
    Show me one NOAA global network tidal gauge data set that supports this.
    Statements like this, prove the how fraudulent these people are.

  23. “Modelling” and “simulated”….GIGO. All complete BS to justify further grants. Time is running out for this lunatic pseudo-science….

  24. “Study finds 24% of West Antarctic ice is now unstable”

    “The research team found the pattern of glacier thinning has not been static over time. Since 1992, the thinning has spread across 24 percent of West Antarctica…”

    =======

    Since when does thinning = unstable?

    Since 1992 there has been a pattern of hair thinning on the top of my head, but I seem to be gaining hair in other places. I know a few people that had all their hair fall out in clumps in about a year… now that is what I consider unstable.

    So, what’s happening to ice in the other 76% of WA? Absolutely no change? Or 52% unchanged (“stable”) and 24% thickening (unsta… no it can’t be that so it would have to be un-unchanged).

    “… the thinning has spread…” OMG it’s contagious, like a virus! Scientists measure stuff, do calculations, write up their results. Whereas people with agendas use this kind of phrasing.

    As for the 4.6mm SLR in 27 years… my toenails grow 40 times faster. So I’ve made a mental note to avoid any oceans when my toenails grow faster than I can walk up a beach with a 2.5% slope. Or maybe 3% to include some allowance for Greenland.

  25. Agreed, H. R.
    I come up with 1.16 hours.

    Basically studying a miniscule portion of continuity.
    e.g. studying 1.16 hours of sleep, breakfast, work, lunch, dinner, evening rest and recuperation i.e. drink and quiet, etc. Then declaring the study finds extraordinary events.

    “Abstract
    Fluctuations in Antarctic Ice Sheet elevation and mass occur over a variety of timescales, owing to changes in snowfall and ice flow. Here, we disentangle these signals by combining 25 years of satellite radar altimeter observations and a regional climate model. From these measurements, patterns of change that are strongly associated with glaciological events emerge. While the majority of the ice sheet has remained stable, 24% of West Antarctica is now in a state of dynamical imbalance.”

    25 years of altimetry; i.e. spotty readings to more comprehensive altimeter readings, combined with a purpose biased regional model that:
    A) Assumes all warming is due to anthropogenic CO₂ emissions.
    B) Magnifies assumptions to catastrophic future ice levels.

    “We developed time-series of surface elevation change across the AIS and within its principal drainage units from ERS-1, ERS-2, ENVISAT, and CryoSat-2 radar altimeter observations recorded between May 1992 and May 2017. …

    To compute elevation, the altimeter range measurements were corrected for
    the lag of the leading-edge tracker,
    dry atmospheric mass,
    water vapour,
    the ionosphere,
    ocean loading tide, and
    temporal variations in surface scattering.

    We also adjusted for elevation changes associated with glacial isostatic adjustment using the IJ05_R2 model (Ivins et al., 2013).

    The surface elevation change time-series were computed (McMillan et al., 2014; Zwally et al., 1989) within regularly-spaced grid cells and during fixed time intervals (epochs).

    In the first instance we generated time-series from each satellite mission independently, and we then combined them by adjusting for the bias occurring during periods of mission overlap.”

    Formatting is mine.
    What an amazing amount of adjusting variables! The elephant’s trunk is functioning as is the tail and tongue.

    “Against these benchmarks, the optimal scenario among those we have considered uses a plane fit elevation change solver, averages measurements in 140-day epochs, interpolates elevation changes over distances of 20 km to fill remaining gaps, uses a 60-month period as the basis of corrections to compensate for correlated fluctuations in elevation and backscattered power, and does not apply a leading edge width correction.”

    How sweet. They smear measurements across areas and infill. Apparently a common procedure when conducting Antarctica research.

    Note their altimetry results, via their multiple variable “2. Ice Sheet Elevation Change” calculations. I suspect their regional model results are inclusive.
    https://www.dropbox.com/s/5982gu189tb4iac/Antarctic-altimetry-A.jpg?dl=0

  26. West Antarctica is the second largest land ice mass in the world (only East Antarctica has more ice), and it contributed 4.6 mm of sea level rise since 1992, or an average of 0.17 mm per year. Over 100 years, at this rate the sea level would rise 1.7 cm, or about 0.67 inch. Do we really need to worry about this?

    • Well, the latest trolls on the board seem to.

      Of course, they also believe AOC was ‘just joking’ about her 12 year doomsday.

  27. I don’t see any mention of how much ocean warming is being talked about.

    A brief scan of a couple articles suggests that the warming might be in the range of measuring instruments’ accuracy, as I’m understanding the information, which makes me wonder why the article does not define numerically exactly how much warming is being discussed.

    One article I skimmed mentioned thousanDTHS of a degree over years.

    Somehow, I think there’s more to it than just this bit of warming. And I also wonder whether ARGO can really measure temps to thousanDTHS of a degree, and what does this really mean, if they can? Couldn’t there be a thousanDTH of a degree difference in water temps over a very short distance? [I don’t know] What exactly would a thousanDTH of a degree difference be a measure of?

    Needless to say, either through ignorance or not understanding, I am not convinced that “warmer” ocean water alone is the cause of this melting.

    I need more info.

  28. You’ve only got to look at the actual paper and table 1 and figure 2A to see just how localised the mass losses are. And based on the last 25 years, its 3/4 of an inch of sea level rise per century from Antarctica. There go the beachfront property prices.

  29. I did the first ascent of Mt. Foster on Smith Island in 1996. We anchored at Deception Island only to find the surrounding water nearly scalding hot. We jumped into the “hot tub” for a much needed bath. Par-broiled prawn drifted past, and we peeled and ate them as we sipped our wine.

    • This sounded unbelievable so I decided to check Deception Island
      “Deception Island exhibits some wildly varying microclimates. Near volcanic areas, the air can be as hot as 40 °C (104 °F), and water temperature can reach 70 °C (158 °F).” This is something that I never imagined in the Antarctic.

  30. I have been looking into the problem of liquid water in the Antarctic, I have read that it only can be found for a few brief weeks in the summer in certain microclimatic areas like the McMurdo Dry Valleys. Also we read that flowing streams can even be a few miles long, but these might be hard to find on a continent larger than the contiguous United States. Now reading this article which estimates that the melting has raised ocean levels significantly, a simple calculation of this would indicate that you would need a river the size of the Mississippi to suddenly appear in the Antarctic, probably a satellite might be able to see this?

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