Flashback: “Irreversible Collapse” of the West Antarctic Ice Sheet – from 1999

Antarctic_Melt-0acf6[1]Guest post by David Middleton

A Geological Perspective on the “Irreversible Collapse” of the West Antarctic Ice Sheet

It’s “old” news, as this publication from 1999 shows us.

Figure 1 Map showing dated locations used to resolve Holocene grounding-line retreat to its present position in the Ross Sea Embayment. Although the detailed structure of past grounding-line positions is unknown, dotted lines show the simplest grounding-line pattern consistent with the dates in the text. (Conway et al., 1999)

Figure 1
“Map showing dated locations used to resolve Holocene grounding-line retreat to its present position in the Ross Sea Embayment. Although the detailed structure of past grounding-line positions is unknown, dotted lines show the simplest grounding-line pattern consistent with the dates in the text.”
(Conway et al., 1999)

The history of deglaciation of the West Antarctic Ice Sheet (WAIS) gives clues about its future. Southward grounding-line migration was dated past three locations in the Ross Sea Embayment. Results indicate that most recession occurred during the middle to late Holocene in the absence of substantial sea level or climate forcing. Current grounding-line retreat may reflect ongoing ice recession that has been under way since the early Holocene. If so, the WAIS could continue to retreat even in the absence of further external forcing…

The collapse (retreat of the grounding line) began about 20,000 years ago. It is irreversible because “the WAIS could continue to retreat even in the absence of further external forcing” and there are no topographic obstacles to prevent it from flowing downhill into the ocean.

One has to wonder why this paper didn’t merit panic-stricken headlines in 1999

It’s the same story, just from the other side of the peninsula.


Reference
H. Conway et al, 1999. Past and Future Grounding-Line Retreat of the West Antarctic Ice Sheet. Science 8 October 1999: Vol. 286 no. 5438 pp. 280-283
DOI: 10.1126/science.286.5438.280

http://www.sciencemag.org/content/286/5438/280.abstract

Abstract

The history of deglaciation of the West Antarctic Ice Sheet (WAIS) gives clues about its future. Southward grounding-line migration was dated past three locations in the Ross Sea Embayment. Results indicate that most recession occurred during the middle to late Holocene in the absence of substantial sea level or climate forcing. Current grounding-line retreat may reflect ongoing ice recession that has been under way since the early Holocene. If so, the WAIS could continue to retreat even in the absence of further external forcing.

(Full text available with registration.)

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About David Middleton

I have been a geoscientist in the evil oil and gas industry for almost 30 years. My favorite hobby is debunking the junk science of the radical environmentalists...Particularly the junk science of anthropogenic global warming.
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35 Responses to Flashback: “Irreversible Collapse” of the West Antarctic Ice Sheet – from 1999

  1. David Riser says:

    Soooo if its been going onward for 20000 years what is the likely hood that it will be done and gone in the next 200?

  2. Rud Istvan says:

    Collapse of the Ross was all the alarmist rage from this paper until the Andrill program in 2005-2007 (if I recall correctly) that showed it hasn’t for three million years and very likely won’t now. anchored by islands, decelerating that sort of thing. The 2014 alarm was fed/manufactured by NASA and by knowingly wrong comments by Rignot of JPL. For example, the 1.2 meters is the calculation of all the ice in the entire catchment basin of 360,000 square km. one of the two papers at issue showed that the interior portions are gaining ice and have virtually no seaward creep. Neither the NASA PR, the NASA website, nor Rignot mention these facts. Pure alarmism, one presumes perhaps in support of the NCA/EPA/Obama agenda in an election year.

  3. RACookPE1978 says:

    On July 2, Obama’s EPA will run out extreme new and very, very expensive ‘clean air” (no soot) restrictions that will effectively shutdown every coal-fired power plant in the US. Such shutdown would occur WITHOUT a vote or debate in Congress because it could occur by “regulation” within the EPA.

    Yes, there is a waiting period, and a “comment period” .. all strategically timed to occur while the republican Congress is out-of-reach and running for office and NOT available to run a law through stopping it.
    And, in the Obama-dictatorship of the democrat-socialist Senate, no law correcting this regulation would ever be permitted to come up for a vote anyway.

    A veto overriding Obama’s refusal to sign will not happen either.

    The Obama dictatorship’s National Climate Assassination (er, Assessment) and the well-orchestrated West Antarctic Ice Shelf collapse publicity fair were run to lead into this 2 July regulation. Wait for the publicity about it! Or, lack of publicity: There are political reasons for the regime to slip this regulation through without publicity, but using the NCA and WAIS as internal justification for ANY economic loss caused by shutting down the power plants.

  4. Latitude says:

    makes me all mushy for the good ol’ days….remembering when more ice was going to make it colder

    1979 : Columbia University Scientist Said That An Increase In Antarctic Sea Ice Could Lead To A New Ice Age

    http://stevengoddard.wordpress.com/2014/02/26/1979-columbia-university-scientist-said-that-an-increase-in-antarctic-sea-ice-could-lead-to-a-new-ice-age/

  5. pat says:

    They will say anything to maintain the funding. The goal is funding, not science. In fact the corruption is so bad the research and work ups have become childish and the Warmists desperately try to say something that was not said the week before.

  6. Billy Liar says:

    The trouble with all these ‘catastrophic’ ice sheet collapses is that they all happen so slowly no-one ever notices. Except the alarmists, of course, looking for an excuse to impose their view of the world on everyone else.

  7. Alan Robertson says:

    Slightly OT, but did anyone else notice that global sea ice anomaly changed negatively by several Thousand Km2 overnight May 14/15 (and has stayed low, since?) Just another data “adjustment”?

  8. norah4you says:

    Pat 9.33
    You are right. Question is, however, how the Warmist managed to miss that it takes knowledge of Theories of Science as well as valid argumentation if a Thesis is to pass and be taken as a serious attempt…..

  9. richard says:

    Ever scare story based on AGW has another reason.

    Floods,

    http://pubs.usgs.gov/fs/fs07603/

    “The frequency of moderate flooding can increase substantially after development. The annual frequency that daily discharge exceeded 1,000 ft3/s on the Northeast Branch of the Anacostia River in Maryland increased from once or twice per year in the 1940s and 1950s to as much as six times per year in the 1990s”

  10. Richard M says:

    The current scare is on the same side of the peninsula, just a few hundred miles nearer … near the Pine Island glacier. Both of these areas are impacted by volcanic activity. A new volcano was found between these two areas last November. The discharge of melt water from the melting ice near the volcano could certainly be a factor in the changes.

  11. Jim Reekes says:

    Rud said, “the 1.2 meters is the calculation of all the ice in the entire catchment basin of 360,000 square km. one of the two papers at issue showed that the interior portions are gaining ice and have virtually no seaward creep”

    Does anyone has a cites to these papers? I’d very much like to read this!

  12. ralfellis says:

    Ooohhhhh, this guy works in the oil industry …. Heretic …. *** (reaches for rabit’s foot, the blue prophylactic eye, and the trusty Bob Dylan album) *** .

    Don’t believe a word he says. Only true Greens are never spin the data to suit their new religion – honest.

    /sarc.

  13. Joe Public says:

    At the time, the Beeb reported this as:-

    “Nature blamed for melting ice

    US scientists have suggested that the gradual melting of the huge West Antarctic ice sheet may not be the fault of humankind – at least not yet.” [My bold]

    http://news.bbc.co.uk/1/hi/sci/tech/467847.stm

    Just 4 days later, the Beeb also reported the ‘good’ news that “Global warming can make sea level plunge”

    In the worst circumstances, the “hole” left behind could result in a sea level drop of 25 metres but Dr Bratton (Dr John Bratton of the US Geological Survey) told BBC News Online that his conservative estimates suggest a drop of up to 1.5m.” [My bold]

    http://news.bbc.co.uk/1/hi/sci/tech/467928.stm

  14. cnxtim says:

    What i see as the difference between 1999 and now, is the massive rise of the publicly funded CAGW congregation, doggedly adhering to one deafening mantra – “for the first time in history. mankind is capable of on a global scale, changing the world by increasing the earth’s temperature by its own actions” .

    The device they they preach is that this is all due to the consumption of underground fuel supplies.
    The flaw is they started with the mantra, THEN without the constraints of good science went looking for the ‘human induced cause’.
    .Episode 9 of the otherwise excellent series Cosmos continues to bleat the mantra – without any scientific basis – pity.

  15. Louis says:

    So the latest paper from Rignot et al., proclaiming the “Irreversible Collapse” of the West Antarctic Ice Sheet, is basically a repeat of this older paper from 1999. Why is it that alarmist researchers can rehash old stuff without having a reviewer say, “The overall innovation of the manuscript is very low,” as they did with the Bengtsson paper?

  16. milodonharlani says:

    Joe Public says:
    May 17, 2014 at 10:39 am

    From the old BBC link:

    “Any temperature rise will start to melt clathrate,” he says. “The apparent massive hydrate melting about 60 million years ago was triggered by an increase in bottom water temperatures of about four degrees centigrade.

    “Therefore, it appears that the process could get going with an increase of even one or two degrees, especially in the polar regions where gas hydrate is abundant.”

    Surely Dr. Bratton must have known that the seas were already warmer in the balmy Paleocene & Eocene than in the frigid present, so it would take a bigger increase than one or two degrees to do the trick now, if in fact it happened then.

  17. hunter says:

    So once again we climate obsessed people cycling back to old, disproven fear mongering tactics.

  18. Mac the Knife says:

    Soooo, it’s been ‘collapsing’ for the last 20,000 years?
    And, at that glacial pace, it is ‘catastrophic’?
    Oh, the horror of it all…

    I like the ‘irreversible’ part of the scare line….
    How do you ‘reverse’ a glacier?
    Anybody ever document a glacier sliding uphill?
    Or document icebergs coalescing back into solid ice pack and then moving back on-land?

  19. Mac the Knife says:

    Rud Istvan says:
    May 17, 2014 at 8:56 am

    Rud,
    Thanks for the ‘background’ info.
    Do you have a citation for that? Or a link? I’d like to read up on that.
    Mac

  20. Rud Istvan says:

    Jim and Mac. I just finished a chapter on this for my next book, with part of it as a possible post at Climate Etc. Let me get to the computer rather than the IPad and I will get you the coordinates, unlocked from paywall. About an hour.

  21. milodonharlani says:

    The present grounding line of the WAIS*, like the position of the massive East Antarctic Ice Sheet, has been stable for about 3000 years, following the retreat shown in the above graphic from 1999.

    *Anderson, J. B.; Antarctic Marine Geology (Cambridge Univ. Press, 1999)

  22. Rud Istvan says:

    Jim and Mac. The two 2014 papers on the Amundsen Sea Embayment (Pine Island, Thwaites, Smith, and three other smaller glaciers) are in GRL and Science. The one on total ice loss is Mouginot et. al., Sustained increase in ice discharging from the Amundsen Sea Embayment, GRL: 2013GL059069 (2014). Available at http://www.ess.uci.edu/researchgrp/erignot/files/grl51433.pdf It has images of creep rate for the entire catchment basin, based on actual gps from a lot of monitoring sites on it.

    Noteworthy because the annual mass loss estimate is 4x the most recent other, by Zwally (also NASA) using ICESat. Available directly on line at http://www.waisworkshop.org/presentations/2011/session4/zwally.pdf For my money, this presentation is the best reliable, unsensationalized current info for Ross, Ronne, Pine Island, Thwaites, and a host of other Antarctic locations of interest. Bottom line is WAIS is very slowly losing net ice mass. Ronne is gaining, Ross is about neutral, Amundsen embayment and a couple of other minor places are losing. Add up WAIS loss, EIAS gain, Greenland loss, and thermosteric rise (from ARGO estimates) and you get the closure problem. The current total is a third less than the supposed satellite altimeter rate of SLR since 1993 of 2.8mm/year. Lots of improperly estimated error in all these estimates is the answer. MSM never mention that issue in their hype.

    The possible future instability of the Thwaites glacier (smaller than Pine Island) is Joughin et. al., Marine Ice Sheet Collapse potentially underway for the Thwaites Basin, Science 344: 735-738 (2014). Available at http://sciences/blogs/liberation.fr/files/glacier-thwaites.pdf. Noteworthy because unlike the mass media hysteria this week (overshadowed by Bengtssongate), the paper actually says the instability (based on modeling only) might start in 200 to 900 years, and IF it did, would amount to 1mm year THEREAFTER. Not now. NASA implied now, for the entire catchment ice mass. Then Goldenburg at the Guardian applied this to all of WAIS (and or confused an impossible 4 feet (1.2 metersNASA) with . Stupidity compounded on stupidity compounded on stupidity.

    The original estimate of the total ice mass of the Amundsen Embayment catchment that was cited by NASA in its 2014 PR is: Rignot et. al., Acceleration of Pine Island and Thwaites…, Annals of Glaciology 34: 189-194 (2002). Available directly on line as is.
    If these links do not work, Google around until you find unlocked copies of the 2014 papers on the sub authors websites. That is what I did to get around the paywalls. Works almost every time.

  23. Joel O'Bryan says:

    The final paragraph of Conway, et al.

    “We suggest that modern grounding-line retreat is part of ongoing recession that has been under way since early to mid-Holocene time. It is not a consequence of anthropogenic warming or recent sea level rise. In other words, the future of the WAIS may have been predetermined when grounding-line retreat was triggered in early Holocene time. Continued recession and perhaps even complete disintegration of the WAIS within the present interglacial period could well be inevitable.”

    The simplest explanation for Rignot and colleagues at UCI paper in the 15 years since Conway, et al Science paper would be that “anthropogenic warming” alarmism is more grant worthy than a WAIS collapse predetermined since the mid-Holocene.

  24. Rud Istvan says:

    mildonharlani, I am fairly certain that is for the Ross ice shelf only, as determined by the ANDRILL program. The grounding line for the Pine Island glacier in the Amundsen Embayment is supposed to have retreated about 20KM (IIRC) since the mid 1990′s. Pine Island broke off the massive iceberg that was indirectly responsible for trapping the Ship of Fools, which provided much Christmas merriment.

  25. milodonharlani says:

    You’re right. It doesn’t apply to the Amundsen Sea. The ~10% of the WAIS drained by the PIG is IMO a special case, not least because of the Hudson Mountain volcano & maybe higher precipitation in its basin (haven’t checked on the latter though, & in any case it’s hard to work in that area; IIRC the 2012 summer expedition had to be cancelled due to even more inclement than normal WX).

  26. Rud Istvan says:

    Yup. Now where in the NASA PR that started this media frenzy is there any mention of the sub glacial newly discovered Hudson volcano. That was, of course, a rhetorical question.
    Regards

  27. milodonharlani says:

    Rud Istvan says:
    May 17, 2014 at 2:04 pm

    Meant Mountains. First wrote Range.

    No wonder the PIG is always the poster child for supposed Antarctic ice mass melting. Its behavior can’t possibly be caused by anything other than CO2.

    When I search for actual summer temperature readings from the PIG, all I find are modeled anomalies rather than real data.

  28. milodonharlani says:

    Ice core record shows Antarctic cooling, 1882-2006:

    http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-11-00496.1

    The abstract states that, “This cooling trend is in contrast to a surface temperature record from Ross Island (Scott Base) where significant spring warming is observed”. Yet the average high T for warmest months (Dec & Jan) at Scott Base is still below freezing.

  29. David Middleton says:

    Rud Istvan on May 17, 2014 at 8:56 am
    Collapse of the Ross was all the alarmist rage from this paper until the Andrill program in 2005-2007 (if I recall correctly) that showed it hasn’t for three million years and very likely won’t now. anchored by islands, decelerating that sort of thing. The 2014 alarm was fed/manufactured by NASA and by knowingly wrong comments by Rignot of JPL. For example, the 1.2 meters is the calculation of all the ice in the entire catchment basin of 360,000 square km. one of the two papers at issue showed that the interior portions are gaining ice and have virtually no seaward creep. Neither the NASA PR, the NASA website, nor Rignot mention these facts. Pure alarmism, one presumes perhaps in support of the NCA/EPA/Obama agenda in an election year.

    The “funny thing” about ice sheets is that they are always either collapsing or expanding. The WAIS was cyclically “collapsing” as far back as the Middle Miocene…

    http://www.sciencedirect.com/science/article/pii/S0012821X03005090

  30. Rud Istvan says:

    All, I am given to understand that Judith will publish the abridged version at CE tomorrow. Enjoy the images from the papers themselves, and from contemporary others.

  31. David Middleton says:

    @Keith,

    Ringnut did get one thing right,

    This part of the continent was likely to retreat anyway, but we probably pushed it there faster. It remains difficult to put a timescale on it, because the computer models are not good enough yet, but it could be within a couple of centuries, as I noted.

    It was likely to retreat anyway. We might have sped up the process… or we might not have. Either way, we won’t know for 200 to more than 1,000 years. Even then, we won’t know if it would have done what it did anyway.

    Otherwise, it is an imminent catastrophe, worthy of bankrupting the United States in a futile effort to do something about it.

    /Sarc

  32. Paul Nottingham says:

    Joe Public

    “Just 4 days later, the Beeb also reported the ‘good’ news that “Global warming can make sea level plunge”

    In the worst circumstances, the “hole” left behind could result in a sea level drop of 25 metres but Dr Bratton (Dr John Bratton of the US Geological Survey) told BBC News Online that his conservative estimates suggest a drop of up to 1.5m.” [My bold]

    http://news.bbc.co.uk/1/hi/sci/tech/467928.stm

    That is a wonderful article but did you notice who wrote it?

    Damian Carrington, Head of Environment at the Guardian.

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