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posted by chromas on Thursday January 17 2019, @07:07AM   Printer-friendly
from the more-than?-or-as-much-as? dept.

Submitted via IRC for Bytram

Antarctica losing six times more ice mass annually now than 40 years ago: Climate change-induced melting will raise global sea levels for decades to come

For this study, [lead author Eric] Rignot and his collaborators conducted what he called the longest-ever assessment of remaining Antarctic ice mass. Spanning four decades, the project was also geographically comprehensive; the research team examined 18 regions encompassing 176 basins, as well as surrounding islands.

[...] The team was able to discern that between 1979 and 1990, Antarctica shed an average of 40 gigatons of ice mass annually. (A gigaton is 1 billion tons.) From 2009 to 2017, about 252 gigatons per year were lost.

The pace of melting rose dramatically over the four-decade period. From 1979 to 2001, it was an average of 48 gigatons annually per decade. The rate jumped 280 percent to 134 gigatons for 2001 to 2017.

 

Four decades of Antarctic Ice Sheet mass balance from 1979–2017 (open, DOI: 10.1073/pnas.1812883116)


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  • (Score: 1, Informative) by Anonymous Coward on Thursday January 17 2019, @09:02AM (18 children)

    by Anonymous Coward on Thursday January 17 2019, @09:02AM (#787825)
    Starting Score:    0  points
    Moderation   +1  
       Informative=1, Total=1
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    Total Score:   1  
  • (Score: 1, Informative) by Anonymous Coward on Thursday January 17 2019, @09:21AM (15 children)

    by Anonymous Coward on Thursday January 17 2019, @09:21AM (#787830)

    "Fact : worldwide sea level +/- 4 mm."

    I would believe they know what happens after death before that they measured the "global sea level" to within 4 mm. It's literally dumber than religion.

    Just read what they are doing and think about their claim to measure to the nearest tenth of a mm:
    https://tos.org/oceanography/article/the-moving-boundaries-of-sea-level-change-understanding-the-origins-ofgeogr [tos.org]

    Eg:

    For example, a 500-km Gaussian smoothing is often applied to GRACE data in order to reduce the impact of short-lengthscale errors in the observations.

    • (Score: 0, Troll) by Anonymous Coward on Thursday January 17 2019, @10:02AM (4 children)

      by Anonymous Coward on Thursday January 17 2019, @10:02AM (#787834)

      You are just so smart, aren't you?

      • (Score: -1, Troll) by Anonymous Coward on Thursday January 17 2019, @10:11AM (3 children)

        by Anonymous Coward on Thursday January 17 2019, @10:11AM (#787835)

        No, it really does not take intellegence to comprehend this. Go measure something to the nearest tenth of a mm. Then do it again.Then think about if it was a moving liquid and you were measuring it while moving thousands of miles an hour from 6 km away, then that a couple of times in the middle of the measurement you had to switch to a completely new tool.

        It is totally unbelievable. It takes zero smarts to understand.

        • (Score: 0) by Anonymous Coward on Thursday January 17 2019, @10:19AM

          by Anonymous Coward on Thursday January 17 2019, @10:19AM (#787836)

          And oh yea, due to multiple overlapping cycles the "true" value is fluctuating by tens, hundreds or even thousands of mm periodically as well.

        • (Score: 2) by DeathMonkey on Thursday January 17 2019, @06:54PM (1 child)

          by DeathMonkey (1380) on Thursday January 17 2019, @06:54PM (#787981) Journal

          It's called an average. Maybe you should look into that, and other basic math skills, before posting?

          • (Score: 1, Touché) by Anonymous Coward on Thursday January 17 2019, @07:22PM

            by Anonymous Coward on Thursday January 17 2019, @07:22PM (#787999)

            Yea, this does look like what a naive use of averages would result in:

            > mean(c(5.2,6.7,5.6,5.5,5.9, 6.5, 8.2))
            [1] 6.228571

            Wow, I could only measure to the tenth of a meter but now all of a sudden I know the average value to an accuracy of a micron, the size of a single bacterium. Isn't it amazing???

    • (Score: -1, Troll) by Anonymous Coward on Thursday January 17 2019, @10:28AM (5 children)

      by Anonymous Coward on Thursday January 17 2019, @10:28AM (#787838)

      I hope the sand you buried your head in is far enough from the seaside. Otherwise you risk some nasty surprises.

      • (Score: 0) by Anonymous Coward on Thursday January 17 2019, @10:37AM (4 children)

        by Anonymous Coward on Thursday January 17 2019, @10:37AM (#787839)

        If I am more uncertain about whats going on with the sea level than you, you conclude I should move towards the sea?

        It is the opposite. The people who know the sea level to the nearest tenth of a mm over the last decades should have a huge advantage in choosing where/when to buy seaside real estate. Are they taking advantage of this superior knowledge?

        • (Score: 2) by Pslytely Psycho on Thursday January 17 2019, @11:06AM (3 children)

          by Pslytely Psycho (1218) on Thursday January 17 2019, @11:06AM (#787842)

          Reading comprehension FAIL. He (she?) stated he hoped you were far enough away from the shore or you might get a nasty surprise.
          Since we now know your education level we can now safely ignore anything you have to say.

          --
          Alex Jones lawyer inspires new TV series: CSI Moron Division.
          • (Score: 0) by Anonymous Coward on Thursday January 17 2019, @11:25AM (2 children)

            by Anonymous Coward on Thursday January 17 2019, @11:25AM (#787849)

            I know what was literally stated. What they meant was that sea level rise makes being near the sea risky, along with something like "denying" it would mean I was at risk of "learning my lesson".

            First, I never denied the sea level rise may be a risk in the future. In fact I am open to much larger rates/amounts of sea level rise since I don't buy into their tenth of a mm precision in sea level measurements. Second, the people who supposedly believe this stuff don't seem to be applying the "knowledge" towards any practical purpose (or are they and I just havent heard about it?).

            Hopefully that clarifies it.

            • (Score: 2) by bzipitidoo on Thursday January 17 2019, @05:02PM (1 child)

              by bzipitidoo (4388) on Thursday January 17 2019, @05:02PM (#787935) Journal

              > I would believe they know what happens after death before that they measured the "global sea level" to within 4 mm

              Because the ocean surface is chaotic, with waves, tides, temperature changes, storm surges, boat wakes, and even the movements of fish making ripples on the surface, you really think it's not possible to measure global sea level to within 4mm?

              It's actually not that hard. One way is to put a big floating object in the water. A gigantic cruise ship or oil tanker works. That smooths out all the little waves. Then, observe its height over a period of days, to smooth out the variations in weather, and also tides. Another way is just use radar from space. Still another way is measure the water level near the shore, record the elevation at high and low tides. Continents are quite nicely steady enough to make that a very good way to measure sea level.

              Anyway, those sorts of objections, that scientists can't measure because they are too stupid to notice, understand, and account for various factors that would affect a measurement, or that water is too chaotic and no one and nothing can measure it, or that measuring instruments are grossly inaccurate and can't be believed, well, they are standard, and wrong, contentions that some scientific illiterates like to push, for reasons that have nothing to do with facts. It won't fool anyone but fellow fools.

              • (Score: 0) by Anonymous Coward on Thursday January 17 2019, @05:38PM

                by Anonymous Coward on Thursday January 17 2019, @05:38PM (#787951)

                I already shared a link above that describes the issues with everything you just wrote. It is in fact not simple at all to do any of those things and (unsurprisingly to anyone who is familiar with data collection) require all sorts of adjustments and approximations and data cleaning.

    • (Score: 3, Touché) by Pav on Thursday January 17 2019, @01:10PM (1 child)

      by Pav (114) on Thursday January 17 2019, @01:10PM (#787875)

      Them thar calculus-meisters can't pull highly precise zero-points from waveforms such as these. That be either fibbing, leg pulling, or black magic worthy of a witch-burnin' such as fourier transforms and the like.

      • (Score: 0) by Anonymous Coward on Thursday January 17 2019, @04:08PM

        by Anonymous Coward on Thursday January 17 2019, @04:08PM (#787908)

        Clearly they can pull such numbers from the readings theyve collected, its just that the uncertanty they report around such numbers is detached from any actual uncertainty sbout the sea level. Its like they are only reporting monte carlo error and some form of "sampling" error while ignoring everything else.

    • (Score: 2) by DeathMonkey on Thursday January 17 2019, @06:42PM (1 child)

      by DeathMonkey (1380) on Thursday January 17 2019, @06:42PM (#787977) Journal

      Fact, you are a liar.

      Here's the figure from the link: 87 (± 4) mm

      Hmmm....seems like you missed something there.

      • (Score: 0) by Anonymous Coward on Thursday January 17 2019, @07:17PM

        by Anonymous Coward on Thursday January 17 2019, @07:17PM (#787997)

        I didn't miss anything. They claim to be able to measure sea level to within 4 mm. The absolute level/change is irrelevant to what I am saying.

  • (Score: 1, Redundant) by bradley13 on Thursday January 17 2019, @05:36PM (1 child)

    by bradley13 (3053) on Thursday January 17 2019, @05:36PM (#787950) Homepage Journal

    Those NASA graphs are a great reference. So the current annual change in sea level is averaging 3.2mm/year.

    I just wish that they would put this in context. One should at least compare it to the sea level rise over the past 2000 years. The rate shown by NASA is about double the historical rate, which exists because we are still in an interglacial period. So AGW may be contributing the other half, or about 1.6mm/year. That's 16cm (6.4") in a century, which is not going to drown any coastal cities.

    I wish we could get the media and politics out of the climate discussion. Everything panders to panic-making - if your article doesn't sound catastrophic, it's going to be ignored. So everything is OMG eleventy, we're all gonna die!! This makes it hard to discern the actual facts and the actual science that might be there.

    --
    Everyone is somebody else's weirdo.
    • (Score: 3, Interesting) by DeathMonkey on Thursday January 17 2019, @06:45PM

      by DeathMonkey (1380) on Thursday January 17 2019, @06:45PM (#787978) Journal

      One should at least compare it to the sea level rise over the past 2000 years.

      Where do you suggest they get that data? 'Cause I'm pretty sure if a study that tried to extrapolate that data was posted here you'd be complaining that it was all estimations and magic numbers.