Extra: NYTimes. Unstoppable Antarctic Collapse Underway

May 12, 2014

I am seeking to get copies of these studies asap.
A lot of cross-talk on this right now. Will update.

NYTimes:

The collapse of large parts of the ice sheet in West Antarctica appears to have begun and is almost certainly unstoppable, with global warming accelerating the pace of the disintegration, two groups of scientists reported Monday.

The finding, which had been feared by some scientists for decades, means that a rise in global sea level of at least 10 feet may now be inevitable. The rise may continue to be relatively slow for at least the next century or so, the scientists said, but sometime after that it will probably speed up so sharply as to become a crisis.

“This is really happening,” said Thomas P. Wagner, who runs NASA’s programs on polar ice and helped oversee some of the research. “There’s nothing to stop it now. But you are still limited by the physics of how fast the ice can flow.”

Two papers scheduled for publication this week, in the journals Science and Geophysical Research Letters, attempt to make sense of an accelerated flow of glaciers seen in parts of West Antarctica in recent decades.

Both papers conclude that warm water upwelling from the ocean depths has most likely triggered an inherent instability that makes the West Antarctic ice sheet vulnerable to a slow-motion collapse. And one paper concludes that factors some scientists had hoped might counteract such a collapse will not do so.

The new finding appears to be the fulfillment of a prediction made in 1978 by an eminent glaciologist, John H. Mercer of the Ohio State University. He outlined the uniquely vulnerable nature of the West Antarctic ice sheet and warned that the rapid human release of greenhouse gases posed “a threat of disaster.” He was assailed at the time, but in recent years scientists have been watching with growing concern as events have unfolded in much the way Dr. Mercer predicted. (He died in 1987.)

Scientists said the ice sheet was not melting because of warmer air temperatures, but rather because of the relatively warm water, which is naturally occurring, from the ocean depths. That water is being pulled upward and toward the ice sheet by intensification of the winds around Antarctica.

Most scientists in the field see a connection between the stronger winds and human-caused global warming, but they say other factors are likely at work, too. Natural variability of climate may be one of them. Another may be the ozone hole over Antarctica, caused by an entirely different environmental problem, the human release of ozone-destroying gases.

Whatever the mix of causes, they appear to have triggered a retreat of the ice sheet that can no longer be stopped, even if the factors drawing in the warmer water were to reverse suddenly, the scientists said. At this point, a decrease in the melt rate back to earlier levels would be “too little, too late to stabilize the ice sheet,” said Ian Joughin, a glaciologist at the University of Washington and lead author of the new paper in Science. “There’s no stabilization mechanism.”

UPDATE – NASA JPL:

The new finding that the eventual loss of a major section of West Antarctica’s ice sheet “appears unstoppable” was not completely unexpected by scientists who study this area. The study, led by glaciologist Eric Rignot at NASA’s Jet Propulsion Laboratory, Pasadena, California, and the University of California, Irvine, follows decades of research and theory suggesting the West Antarctic Ice Sheet is inherently vulnerable to change.

Antarctica is so harsh and remote that scientists only began true investigation of its ice sheet in the 1950s. It didn’t take long for the verdict on the West Antarctic Ice Sheet to come in. “Unstable,” wrote Ohio State University glaciologist John Mercer in 1968. It was identified then and remains today the single largest threat of rapid sea level rise.

Why is West Antarctica’s ice sheet considered “unstable”?

The defining characteristic of West Antarctica is that the majority of the ice sheet is “grounded” on a bed that lies below sea level.

In his 1968 paper, Mercer called the West Antarctic Ice Sheet a “uniquely vulnerable and unstable body of ice.” Mercer based his statement on geologic evidence that West Antarctica’s ice had changed considerably many, many millennia ago at times when the ice sheets of East Antarctica and Greenland had not.

In 1973, University of Maine researcher Terry Hughes asked the question that scientists continue to investigate today. The title of his paper: “Is The West Antarctic Ice Sheet Disintegrating?” In 1981, Hughes published a closer look at the Amundsen Sea region specifically. He called it “the weak underbelly of the West Antarctic ice sheet.”

Here’s the cause for concern: When the ice sheet is attached to a bed below sea level, ocean currents can deliver warm water to glacier grounding lines, the location where the ice attaches to the bed.

Scientists recognized that this is the first step in a potential chain reaction. Ocean heat eats away at the ice, the grounding line retreats inland and ice shelves lose mass. When ice shelves lose mass, they lose the ability to hold back inland glaciers from their march to the sea, meaning those glaciers can accelerate and thin as a result of the acceleration. This thinning is only conducive to more grounding line retreat, more acceleration and more thinning. In this equation, more ice flows to sea every year and sea level rises.

But that’s not all.

Beginning with research flights in the 1960s that made radar measurements over West Antarctica, scientists began to understand that, inland of the ice sheet’s edge, the bed slopes downward, precipitously, in some cases.

This downward, inland slope was theorized decades ago, but has been confirmed and mapped in detail in recent years by airborne campaigns such as NASA’s Operation IceBridge. In some spots the bed lies more than a mile and a half below sea level. The shape of this slope means that when grounding lines start to retreat, ocean water can infiltrate between the ice and the bed and cause the ice sheet to float off its grounding line.

Why is the Amundsen Sea region more at risk than other parts of West Antarctica?

In addition to the ice sheet being grounded below sea level, there are three main reasons. First, the glaciers here lack very large ice shelves to stem ice flow. Second, they aren’t “pinned” by obstructions in their beds except in a few small places, unlike the Ronne and Ross shelves which are pinned down by large islands. Third, as first observed in the 1990s, the area is vulnerable to a regional ocean current, ushered in by the shape of the sea floor and the proximity of the circumpolar deep current. This current delivers warm water to grounding lines and the undersides of ice shelves in the region.

The pace and magnitude of the changes observed in this region match the expectation that Amundsen Sea embayment glaciers should be less stable than others. In some cases, the changes have outstripped expectations.

Pine Island and Thwaites glaciers have experienced significant flow acceleration since the 1970s. Both saw the center of their grounding lines retreat dramatically. From 1992 to 2011, Pine Island’s grounding line retreated by 19 miles (31 kilometers) while the center of the Thwaites grounding line retreated by nearly 9 miles (14 kilometers). Annual ice discharge from this region as a whole has increased 77 percent since 1973.

What would a loss of the Amundsen Sea region mean for sea level rise?

Even as Rignot and colleagues suggest that loss of the Amundsen Sea embayment glaciers appears inevitable, it remains extremely difficult to predict exactly how this ice loss will unfold and how long it will take. A conservative estimate is that it could take several centuries.

The region contains enough ice to raise global sea levels by 4 feet (1.2 meters). The most recent U.N. Intergovernmental Panel on Climate Change (IPCC) report estimates that by 2100, sea level will rise somewhere from just less than 1 foot to about 3 feet (26 to 98 centimeters). But the vast majority of these projections do not take into account the possibility of major ice loss in Antarctica. Rignot said this new study suggests sea level rise projections for this century should lean toward the high-end of the IPCC range.

The Amundsen Sea region is only a fraction of the whole West Antarctic Ice Sheet, which if melted completely would raise global sea level by about 16 feet (5 meters).

What are NASA and other science agencies doing to better understand this vulnerable region and its potential impact on global sea level?

To better understand how this section of the ice sheet has changed in recent decades, scientists from NASA and research institutions around the world have made field campaigns to the region and used every airborne and spaceborne tool at their disposal, including NASA satellites and those launched by space agencies in Europe, Japan and Canada.

The National Science Foundation has funded major field campaigns to West Antarctica, including POLENET, which place Global Positioning System (GPS) stations in the area to measure geological changes. A campaign to the Pine Island Glacier ice shelf led by NASA glaciologist Bob Bindschadler measured variables such as water temperature and melting rate at the underside of the ice shelf.

NASA’s Operation IceBridge, which began in 2009, continues to fly one extended research campaign over Antarctica each year. IceBridge flights put multiple scientific instruments over key regions of the ice sheet to measure glacier thinning, the shape of the bed and other factors.

In 2017, NASA will launch ICESat-2, the follow-up mission to ICESat, which operated from 2003 to 2009. ICESat-2 will use laser altimetry to make precise measurements of glacier heights. Combined with the ICESat and IceBridge data records, the ICESat-2 measurements will allow for a continuous record of year-over-year change in some of the most remote regions of the world.

 

45 Responses to “Extra: NYTimes. Unstoppable Antarctic Collapse Underway”


  1. […] I am seeking to get copies of these studies asap. A lot of cross-talk on this right now. Will update. NYTimes: The collapse of large parts of the ice sheet in West Antarctica appears to have begun …  […]

  2. omnologos Says:

    Worse than we thought. Unstoppable. Several centuries. Debunked warming picture included.

    Next!


    • Worse than we thought. Unstoppable omnologos BS

      • omnologos Says:

        Weren’t we going to die by 2100 or something, just the other day?

        it’s amazing how scrambled the CAGW message has become.

        • ontspan Says:

          Yeah, we know that don’t get it. Just don’t blame others for your own failings. Thanks.

        • Andy Lee Robinson Says:

          You are correct. All of us will die by 2100.

          It’s our descendants that will have a tough time because of deadheads like you.

          • omnologos Says:

            last thing before going to bed…this “descendant” meme is truly meaningless. not one of the generations before us could have imagined the world we live in and the challenges we face, let alone plan any action to better our present lot.

            900 years ago it was 1114AD. Can we imagine anything they could’ve consciously done to improve our society and environment of 2014?

            200 years ago it was 1814AD. Can we imagine anything they could’ve consciously done to improve our society and environment of 2014?

            Me neither.

            Likewise it’s meaningless to think we can do anything consciously to improve the lives of the 24th or 27th or 30th century.


          • 945 years ago it was 1069 AD and William the Conqueror began a series of campaigns to take Northern England. Do you think he or anyone else was planning to go to the moon back then? 245 years ago it was 1769 and Daniel Boone crossed the Appalachians to explore the Kentucky region. Do you think he or anyone else was planning to go to the moon back then? 55 years ago it was 1969… Why the silly idea that anyone could ever successfully go to the moon is easily disproven using the argument ad providentiam.

            /SARC


          • Oh dear… I’m all out of green ink.

          • jimbills Says:

            Omno, we’re not talking about improving the world. We’re talking about trying to leave the world in roughly the same shape that we received it.

            Analogy: a son inherits a house from his parents, and knows he will leave the house eventually to his children. He hears from an expert that leaving the windows open on the top floor in a rainstorm will cause water damage to the floors and support beams. He can also see this damage himself after a few storms. Does he: 1) decide that his children will be fine getting the house in that shape, or 2) decide that it might be a good idea to start closing the windows?

            The house has already received some water damage. There isn’t much to do about that, but isn’t it better to prevent more?

          • omnologos Says:

            Jimbills – it’s good you make the son/parents analogy. We can of course and do plan ahead for the next generation. My father had my age in 1989 and they’ve done it good on abating a lot of pollution.

            However my grandads had my age respectively in 1943 and 1954 and really I cannot fault them for ultimately increasing pollution. They were also thinking of their children: the former had to scramble to prevent them from starving as US and Nazi troops were fighting a few miles away . The latter was working hard to improve their status as Italy was moving from a poor rural economy to the third Continental powerhouse…it just wasn’t time for niceties such as removing particulate from diesel exhaust. Am not sure they had a viable and cheap technology for that.

            We could go back. One of the great grand’s was born in 1889 so would’ve been 47 in 1936. Did they know about the murderous role cars were starting to have? am not sure what his daily problems were really.

            35 years is a reasonable horizon for the future. 60 or 71, too much. 77 is beyond imagination. That’s why we should talk about 2049AD at most . 2100 or even the XXIV century, it’s meaningless.

          • omnologos Says:

            Correction…dad was 47 in 1979 not 1989.

        • jpcowdrey Says:

          The ordinary person does not necessarily have the scrambled cognitive abilities that maurizio has.

    • redskylite Says:

      As you undoubtedly know much of the Western Antarctic ice sheet is below sea-level (due to isostatic adjustment) and subject to runaway ice melt,

      Heinrich events (armadas of ice bergs, breaking off and traversing the oceans) ) last for around 750 years and the onset can occur within a few years. With what is going on in the East (Pine Island), the west of Antarctic and Greenland means the reality of countries like Bangladesh and US cities being overwhelmed by sea level rise is becoming a stark reality.

      If you want to laugh it of as alarmist that’s fine, as so presumably you would do on hearing the news of a super-volcano popping or an asteroid approaching.

      • omnologos Says:

        as should be clear by now I don’t discuss science here, or at least I try not to. It is obvious that I interpret it differently than the host and most of you guys, and there is no point in confirming a truism.

        however, we can and often discuss the “message” and its presentation. in this case it’s not much a matter of what is laughable (from what I have read so far, that’s 99% due to overhyping title writers)…what I find obvious is that this “news” will only add confusion for the casual onlooker, ie for 99% of the voters.

        they were told to worry about 2100AD, now they read of a collapse for 200 to 900 years in the future, that is maybe the 30th century. such a collapse can’t possibly matter, if you are worried about 2100AD. on the other hand, if you are not worried about 2100AD, you will be even less worried about 2300AD or the XXX century.

        I suspect the hype will kill this piece of research from history. Then in a couple of years we will be back at square one, as Andy Revkin just noted.

        All more the reason to reject hype in principle. Including words such as “unstoppable”.

        • redskylite Says:

          I don’t think anyone has been told to worry about anything, and much of the global warming effects are predicted to occur over very long periods of time, should I not be concerned about people in the future, whether 2100, 2200, 2300 or 2400. are they too far of into the future to be of concern to you ?

          We need new energy sources i.e of around 20 terawatts of carbon free energy by the year 2100, we need all of today’s non carbon technology (wind, solar, nuclear, hydro, geothermal, tidal) – plus inventing a few more long term ideas (such as harnessing the powerful jet stream, even moon based solar). We will need geoengineering at some time just to mitigate (like atmospheric CO2 scrubbing using a base), but it is far too late to prevent sea level rise and the consequences on countries like Bangladesh.

        • jpcowdrey Says:

          It is blindingly obvious maurizio interprets science differently than scientists.

          It should be clear by now that the hope of humanity doesn’t rest on the oblivious short-sightedness of maurizio and his ilk. Thank goodness!

          • omnologos Says:

            You make me laugh, JP. None of the people who thought of the 7th generation rule lived in a world where seven generations ago the first intercity railway in the world had just opened, and now we’ve got Teslas.

  3. dumboldguy Says:

    The tipping points loom ever closer. What impact will the Super El Nino have on both the Antarctic and Greenland ice sheets. When will the reinforcing feedbacks that some want to deny become evident? Is McPherson correct?

    • omnologos Says:

      When? On Sunday, October 23, 4004 AD. Ussher was right! (sort of)


    • Oh look, amnologic is trying not to discuss science. How precious. And now he is trying not to discuss logic. I can’t help it. Must… seek….. intelligent… life…

      Meanwhile, whats the betting line on massive El Nino next year? And SLR has to be revised because of Antarctic. California drought? Where is the good news? In all the denier obfuscation we may have missed how poorly Antarctic was doing.

      • omnologos Says:

        Why all the fuss about the el Nino, I do not understand. If there will be one or there won’t be, nothing will change about climate science.

        Also as long as there is no established linkage between agw and el Nino, nothing of el Nino will matter wrt agw.

        Furthermore in general terms of climate change, if the el Ninos keep coming as spaced apart as ever, there won’t be any change in climate. Of course it will all be different if, say, we had 10 el Ninos in a row, yearly.

        • dumboldguy Says:

          The operative words in this Omnidiotic comment are:

          I DO NOT UNDERSTAND

          Ignore the rest.

          • omnologos Says:

            Yes dumbey you do not understand. Perhaps that’s the reason for this inane running commentary of yours, always trying a bit of exegesis on this or that commenter. And usually failing.

          • dumboldguy Says:

            “Usually failing”? Actually, the inverse is true, and always is with you, if you were able to see and understand. Omno the demented rooster is again strutting in the barnyard and AGAIN declaring victory over those of us who have pulled off all his feathers (I am not alone).

            Get a mirror and use it to look at the “thumbs down” you have garnered on this thread, Omno. Don’t look directly up at them because there are so many they will poke the lenses out of your glasses and hurt your eyes.

            Yes, you do NOT understand and you do NOT “talk science” here. And I am done talking to you on this thread. Reading your crap causes me to lose IQ points, and I’d rather become demented the old-fashioned way—-by simply getting older.

        • redskylite Says:

          Well you asked “Why all the fuss about the El Nino” ?,

          Why am I excited about it ?

          Being regarded as a “warmist” by certain camps, who keep on harping on about the so called hiatus, I am excited because there is a possibility of heat being transferred back from the oceans to the land and the surface temperature trend will clearly and indisputably keep on its long term upward trend.

          Why do I want to see that ? because I want to see this subject being taken seriously and serious action being taken by all governments, populations and businesses, Carbon Dioxide does create warming long term. Our habitats and health are threatened and in danger. If a baby gets a fever of 1 or 2 degrees higher you take him or her to the doctor. Man has never existed in 2 degrees above normal temps (last 200,000+ years), what makes you think he will survive, when food supplies and water runs low or out.

          I am also excited as a person interested in Earth sciences, because of the way patterns may be changing, oscillation patterns may be breaking down. What is happening to the PDO is of specific interest to me, and I am watching the ice melt and CO2 charts too, as well as world wide health, floods, droughts data. Why ? because I am retired and have the time, I am also trying to educate myself about the issues by taking on-line University courses and lectures.

          I understand your position that droughts, storms, tempest, medieval warming, little ice age, all occurred before in the past, (but there is an explanation for most of that), there is no explanation for the current warming and melting that is occurring other than CO2 – that is the smoking gun.

          Even if you don’t agree with my view, do you understand why I am excited now ?

          • omnologos Says:

            almost, redskylite…we keep hearing about weather vs climate. Wouldn’t a single el Niño be “weather”?

            That’s why I suggested a “smoking gun” for portentous (=”dangerous”) climate change would be a very uncommon and unexpected series of el Niños one after the other.

            There is also the question about heat exchange…if a non-AGW mechanism such as el Niño can transfer heat from the ocean to the atmosphere, there is bound to be a correspondent non-AGW mechanism doing the exact opposite – otherwise the oceans would have boiled away long ago.

            IOW the much-sought-after hypothesis that AGW is hiding in the deep cannot rely on the PDO – at least not on a PDO that manifests itself in well-established spatial and temporal patterns.

  4. Hay Gee Says:

    In 2007 Al Gore the godfather of the global warming hoax predicted that by 2014 all Arctic Ice would be gone.

    • Angor Wat Says:

      Actually you are wrong. Al Gore misrepresented a study by Maslowski.

      Maslowski also did not say “by 2013” in his original research in 2007 or when it was republished in 2009. This grandstanding about sea ice and Gore, for whatever reason, is a huge and egregious deception. The actual prediction from Maslowski’s 2009 publication is, “Autumn could become near ice free between 2011 and 2016.”

      And he dident even say that. “Should the present trend of sea ice continue, some models suggest that arctic ocean could become near ice free in the summer time within one decade.”
      And then there is the graph.

      Laying and misrepresent the fact wont get you no where here. Its actually way worse then Gores misrepresentation.

      http://www.docstoc.com/docs/41286311/The-freshwater-budget-of-the-Nordic-seas

    • redskylite Says:

      Totally wrong again, Maggie Thatcher (British conservative PM) was the godmother of global warming (long before Al Gore), and Svante August Arrhenius (Swedish scientist) born 1859 was the godfather.

      When will people like you listen and take action on this menace which we are condemning our future generations and co-inhabitants too.

      So far we have emitted around 500 gigatons of Carbon into the biosphere jointly by (fossil fuel and deforestation) for nearly a 1C degree rise, if we emit the same again we are on course for a two degree C + rise. Wake up and smell the roses.


    • Question the Hay Gee: how do you have a hoax promoted by thousands of researchers around the world, but the handful of shills working for the Koch Bros. aren’t promoting a hoax? Normally a hoax is the result of a few promoting the falsehood. Otherwise it gets discovered.

    • jsam Says:

      Ok, you win Denier Derp of the Day. In the end it wasn’t even a contest.

      Keep up the good work. It certainly gives me a good laugh.

  5. Wes Says:

    Apparently Hay Seed has decided to comment here to make O-Log look moderate by comparison. Well, it’s not working.

    I sincerely hope that McPherson is not correct – about the timing, certainly, but also about what is the best we can do. It’s looking less and less likely that we can hold sea level rise to something less than very disruptive. Perhaps we can offer beachfront property in Miami to all the deniers.

    • jimbills Says:

      If the evidence doesn’t support a hoped-for outcome, then hope is irrational. It’s blinding oneself to the likeliest outcome, hoping somehow it will magically work out. Hope, in this case, actually prevents necessary action, further ensuring the likelihood of the undesired outcome.

  6. andrewfez Says:

    I have a tiny bit of property on Hilton Head, SC. The original homes built there before the 1980’s weren’t built on any type of raising (post 80’s, I think the law said builders had to build stuff so that their ground floors were 14 feet about sea level). At present, May 2014, owners are starting to have a hard time selling these older, unraised homes because flood insurance is starting to become an issue (Biggs-Waters). No one wants to catch a falling knife.

    They’ve been dredging the oceanic shelf and pumping sand back up onto the beach these last 20 or 30 years. And a few years ago they pulled up a significant part of the sand dunes, sea oats and coastal chaparral (you know, the stuff that keeps the beach from eroding) near my place, in what looked like an attempt to make the beach look bigger than it was. I never got a credible story as to why this was done. And this is all along a natural harbor, where there aren’t big waves or such.

    For those that don’t follow markets, I will say that the market anticipates changes and bakes into current prices an instrument’s or asset’s future prospects. Long before real destruction occurs, the market will have punished those that hold their beach homes…


  7. […] NYTimes. Unstoppable Antarctic Collapse Underway […]


  8. […] timed for this week’s bad news about Antarctic melt.  When we last looked in on the North Carolina legislature, they were outlawing the study of sea […]


  9. […] Dr. Mauri Pelto is one of the world’s most distinguished and respected glaciologists. I asked him to chat this week following news about unstoppable glacial melt in Antarctica. […]


Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: