New from NASA: East Antarctic Acting Up

January 9, 2019

totten_lower

East Antarctica is supposed to be the most extremely stable ice on the planet. Turns out it’s changing with unsettling speed.

NASA:

East Antarctica has the potential to reshape coastlines around the world through sea level rise, but scientists have long considered it more stable than its neighbor, West Antarctica. Now, new detailed NASA maps of ice velocity and elevation show that a group of glaciers spanning one-eighth of East Antarctica’s coast have begun to lose ice over the past decade, hinting at widespread changes in the ocean.

In recent years, researchers have warned that Totten Glacier, a behemoth that contains enough ice to raise sea levels by at least 11 feet (about 3 meters), appears to be retreating because of warming ocean waters. Now, researchers have found that a group of four glaciers sitting to the west of Totten, plus a handful of smaller glaciers farther east, are also losing ice.

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“Totten is the biggest glacier in East Antarctica, so it attracts most of the research focus,” said Catherine Walker, a glaciologist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who presented her findings at a press conference on Monday at the American Geophysical Union meeting in Washington. “But once you start asking what else is happening in this region, it turns out that other nearby glaciers are responding in a similar way to Totten.”

For her research, Walker used new maps of ice velocity and surface height elevation that are being created as part of a new NASA project called Inter-mission Time Series of Land Ice Velocity and Elevation, or ITS_LIVE. Researchers with ITS_LIVE will be launching a new initiative in early 2019 to track the movement of the world’s ice, which includes the creation of a 30-year record of satellite observations of changes in the surface elevation of glaciers, ice sheets and ice shelves, and a detailed record of variations in ice velocity starting in 2013.

Walker found that four glaciers west of Totten, in an area called Vincennes Bay, have lowered their surface height by about 9 feet (almost 3 meters) since 2008—before that year, there had been no measured change in elevation for these glaciers. Farther east, a collection of glaciers along the Wilkes Land coast have approximately doubled their rate of lowering since around 2009, and their surface is now going down by about 0.8 feet (0.24 meters) every year.

 

These levels of ice loss are small when compared to those of glaciers in West Antarctica. But still, they speak of nascent and widespread change in East Antarctica.

“The change doesn’t seem random; it looks systematic,” said Alex Gardner, a glaciologist with NASA’s Jet Propulsion Laboratory in Pasadena, California, lead of ITS_LIVE and a participant in the press conference. “And that systematic nature hints at underlying ocean influences that have been incredibly strong in West Antarctica. Now we might be finding clear links of the ocean starting to influence East Antarctica.”

Walker used simulations of ocean temperature from a model and compared them to actual measurements from sensor-tagged marine mammals. She found that recent changes in winds and sea ice have resulted in an increase to the heat delivered by the ocean waters to the glaciers in Wilkes Land and Vincennes Bay.

“Those two groups of glaciers drain the two largest subglacial basins in East Antarctica, and both basins are grounded below sea level,” Walker said. “If warm water can get far enough back, it can progressively reach deeper and deeper ice. This would likely speed up glacier melt and acceleration, but we don’t know yet how fast that would happen. Still, that’s why people are looking at these glaciers, because if you start to see them picking up speed, that suggests that things are destabilizing.”

There is a lot of uncertainty about how a warming ocean might affect these glaciers, due to how little explored that remote area of East Antarctica is. The main unknowns have to do with the topography of the bedrock below the ice and the bathymetry (shape) of the ocean floor in front of and below the ice shelves, which govern how ocean waters circulate near the continent and bring ocean heat to the ice front.

For example, if it turned out that the terrain beneath the glaciers sloped upward inland of the grounding line—the point where glaciers reach the ocean and begin floating over sea water, forming an ice shelf—and featured ridges that provided friction, this configuration would slow down the flow and loss of ice. This type of landscape would also limit the access of warm circumpolar deep ocean waters to the ice front.

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23 Responses to “New from NASA: East Antarctic Acting Up”

  1. dumboldguy Says:

    “Those two groups of glaciers drain the two largest subglacial basins in East Antarctica, and both basins are grounded below sea level,” Walker said. “If warm water can get far enough back, it can progressively reach deeper and deeper ice. This would likely speed up glacier melt and acceleration, but we don’t know yet how fast that would happen. Still, that’s why people are looking at these glaciers, because if you start to see them picking up speed, that suggests that things are destabilizing.”

    There is a lot of uncertainty about how a warming ocean might affect these glaciers, due to how little explored that remote area of East Antarctica is. The main unknowns have to do with the topography of the bedrock below the ice and the bathymetry (shape) of the ocean floor in front of and below the ice shelves, which govern how ocean waters circulate near the continent and bring ocean heat to the ice front.

    If, would likely, we don’t know, suggests, and there is a lot of uncertainty, little explored—–WHEN are we going to get ahead of the curve on all this yada-yada?

    (Answer—-best time—20 years ago, second best time—-tomorrow, most likely time—only after tipping points have been reached).

    • doldrom Says:

      There’s also isostatic rebound of the crust when glacier weight diminishes. This is a negative feed back that mitigates the speed at which the grounding line would recede, but models combining all the factors that are emerging are a long way from perfection as yet. Changes to atmospheric and ocean circulation and shifts in weather and wind could all play roles as things progress, many such developments cannot be estimated well at present. In general, advances in understanding glacier dynamics have proved somewhat frightening.

    • redskylite Says:

      For interest a Kiwi team, down at Scott Base, are working on narrowing some of the uncertainties, reported today in my local newspaper. Very specialized (and useful) occupation analyzing ice dynamics, in the age of rampant greenhouse gas emissions.

      “Getting a clearer picture of what several degrees of global warming might mean for the frozen continent – and the 60m of global sea level rise it holds – has become an increasingly urgent mission for scientists.

      “In both Antarctica and Greenland ice flows from the land to the sea – and an increase in the rate of flow of ice from the land to the sea will cause global sea levels to rise,” explained the study’s leader, Professor David Prior.

      “It is clear that global climate change will have this effect. What is less certain is the rate of sea level change that will occur in the next few decades.”

      https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=12187867

  2. Sir Charles Says:

    Strange winter again. Amazingly warm still here in IRL. Meanwhile the European Alps are snowed in. Germany’s south and Austria hit worst. Well. They’re experiencing now in the winter the same torrential rainfalls they’ve been experiencing during the summer time in recent years. Last December some smaller rivers down the Alps were as high as they’re usually in spring. That’s what you call early ice melt.

  3. Terry Donte Says:

    One study does not mean much. The study does suggest that more studies should be done and soon. The problem is the period being looked at is pretty small, a few decades or less and may not mean much or it could mean a lot. The ice elevations were mostly an educated guess before the satellites came along so all those older measurements are suspect.

    The cost of such research is pretty small in the budgets of NASA and NOAA but that would mean some bureaucrat would have to forget their favorite spending so the spending will most likely never be done on a consistent and widespread basis to look at all the larger ice sheets in Antarctica. Perhaps we could get Pelosi and the rest of the democrats to stop paying attention to the wall and pay attention to this. If the ocean were to rise 11 feet Obama’s home in Hawaii would be under water and we cannot allow that to happen.

    • sailrick Says:

      Yeah like it’s the Democrats blocking climate research, and not the AGW denying Trump and GOP

      • J4Zonian Says:

        It’s the corporate duopoly–both Republicans, who deny climate catastrophe is happening, and most Democrats, who admit it’s happening and want to immediately sit down and count their money in order to stop it. They both oppose the few Democrats in Congress who want to do something that will actually do anything–for starters, a climate committee with subpoena power and charged with coming up with a comprehensive plan for a climate mobilization/Green New Deal. If we expect civilization to survive, the Congressional members of the duopoly caucus will have to be removed from power one way or another.

      • rhymeswithgoalie Says:

        Sweet news to me:

        Even India, which had settled on coal a decade ago as the fuel that would help it industrialize, is now saying that solar energy is critical to such aims: it plans to meet 40% of its electricity from sustainable fuels by 2030. That’s because it is cheaper and cleaner than coal, while its air and water quality have become almost unbearable. As a result, it has decided against erecting several hundred coal plants and it has chosen instead to build 100,000 megawatts of solar, which is a difficult goal given its current infrastructure.

        • dumboldguy Says:

          More OT maundering, distraction, and deflection by RWG. Just another attempt to “support” Chucky and build the “brand”.

          So, India SAYS it hopes to get a whole 40% of its electricity from RE by 2030? What does that have to do with ice in east antarctica? (To say nothing of the fact that India is not likely to meet that goal, just as so may other nations are failing to do). You should try to be smarter in your teamwork with Chucky. Maybe you need to take some time off again for some retraining?

  4. redskylite Says:

    ‘Like listening to the song of the earth’: New Antarctica exhibit opens

    “By giving viewers a slice of life in Antarctica, and letting them hear the voices of scientists, people will get the message.”

    “What I hope they’ll realise is that climate change is real, and it’s much more urgent than they realise.”

    https://www.smh.com.au/environment/climate-change/a-3d-voyage-to-antarctica-by-a-filmmaker-20190101-p50p3l.html

  5. Sir Charles Says:

    Earth’s magnetic field is acting up and geologists don’t know why

    Erratic motion of north magnetic pole forces experts to update model that aids global navigation.

    Mass balance?

    • dumboldguy Says:

      MASS BALANCE? LMAO!

      When is Chucky going to take the science classes he needs to understand the unending stream of inane “look at me’s” he posts? The weight of the water on earth makes up abut .05% of the total mass of the planet, and less than 2% of that is bound up in ice, which is spread out anyway. So, that’s .001%—-hardly enough to create a “mass balance” problem even if it was piled in one spot, and the magnetic field of the Earth had nothing to do with what’s going on at the surface of the planet anyway.

      Certainly not as much of a mass balance problem as the shifting of the mass of Guinness-soaked sawdust inside Chucky’s head that produces mass ignorance.

      • rhymeswithgoalie Says:

        Certainly not as much of a mass balance problem as the shifting of the mass of Guinness-soaked sawdust inside Chucky’s head that produces mass ignorance.

        What is your fucking problem?

        • dumboldguy Says:

          Any problems I’m having with my sex life are for sure none of your business, RWG, and it’s impolite for you to ask.

          My “problem” with Chucky has been spelled out many times in many ways here. My highly trained crap detectors tell me that he’s not an honest member of the Crock community, just as I am befinning to believe that YOU are not, as demonstrated by your defense of Chucky.

          Another of my strengths is pattern analysis—-I keep track of the frequency and times of Chucky’s posts, as well as yours, and have seen some interesting patterns. Do you remember my asking why both you and Chucky disappeared from Crock for a week or ten days immediately after the midterm blue wave? You never answered. Hmmmmm(?)

          • rhymeswithgoalie Says:

            I only get notifications on disqus-based forums now. I turned off WordPress notifications because I was getting spam.

            I don’t read Crocks until after I’ve done going through 2 busy Patheos blogs, at which point it is competing with Science-Based Medicine blog, Respectful Insolence, a law blog, about 10 podcasts to which I have subscribed and a few YouTube channels.

            I’ve sampled some of Sir Charles’ links, and have found several that are interesting to me (like the MIT molten salt ceramic pipe article, which I forwarded to my sister). I don’t get why you whine about them so incessantly.

            So, if you’ll excuse me, I’ll take a break from being a dishonest member of the Crock community and go back to whatever “conspiracy” I was supposed to be involved in back in November.

          • dumboldguy Says:

            You turned off WordPress notifications? That means you have to work awfully hard to access Crock and sort out new posts and new comments on older posts. Yet you seem to have a lot to say—you make many comments across a number of threads.

            And you “don’t read Crocks until after you’ve done going through 2 busy Patheos blogs, at which point it is competing with Science-Based Medicine blog, Respectful Insolence, a law blog, about 10 podcasts to which you have subscribed and a few YouTube channels”. That rates an Omnos-type WHAT TF? Patheos, science based medicine, a law blog, TEN podcasts, and a FEW Youtube channels? I call bullshit on ALL of that—-it just doesn’t add up. Even if you ARE working an eight hour day six days a week trolling, as analysis of Chucky’s posting shows he does, that’s an awful lot—-do you get overtime?.

            As for my “incessant whining”, that’s a nice try at turning this back on me, but YOU and CHUCKY (or your masters) have not been smart enough to hide the patterns that set my crap detectors wiggling, and your slick attempts at deflection like “I’ll take a break from being a dishonest member of the Crock community and go back to whatever “conspiracy” I was supposed to be involved in back in November” are no answer to my question about why you both disappeared right after the election. Are you EVER going to answer that question?

            And of course your fellow troll Chucky “tag teams” in with some cleverness to prove my point, while of course totally ignoring “des Pudels Kern” of my arguments. He should have kept his mouth shut.

            “See you in November for further conspiracies”, Chucky says? Don’t wait until then, folks—-the “conspiracy” is ongoing, although it has taken a different tack since the time taken off after the mid-term election for “retraining”

          • Sir Charles Says:

            Thanks for coming to “des Pudels Kern” rhymeswithgoalie.

            See you in November for further conspiracies 😉

    • rhymeswithgoalie Says:

      “Mass balance?”

      Not even close. The magnetic fields generated by the planet’s core are as independently wacky as anything we’ve studied, and would require shipload of computrons to model. We don’t have any control over whether the magnetosphere’s protection from the Solar wind completely collapse.

      At least we can pretend we’ll be able to hold back carbon emissions below 2°C.


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