Announcement

Collapse
No announcement yet.

Greenland retained 99.7% of its ice mass in 20th Century!!!

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Greenland retained 99.7% of its ice mass in 20th Century!!!

    Naturally, the Real Clear Science headline actually read…

    Greenland Lost 9 Trillion Tons of Ice in Century


    Which sounds even more serious than the original headline…



    One would think that the fact that 99.7% of Greenland’s ice sheet survived the 20th Century might just be more scientifically relevant than a 0.3% loss… But I guess that doesn’t make for a very dramatic headline.

    Here’s the math…
    First I converted 9 trillion tons to metric tonnes.

    9,000,000,000,000 tons = 8,164,662,660,000 tonnes

    Then I converted tonnes to gigatonnes.

    8,164,662,660,000 tonnes = 8,165 gigatonnes

    Then I converted gigatonnes of ice to cubic kilometers, assuming 1 Gt = 1 km3.

    8,165 Gt ~ 8,165 km3

    Note: This conversion is inexact because ice is slightly less dense than water. But it is close enough for this exercise.

    Now that I roughly knew the volume of ice loss during the 20th century, I needed to know how much ice volume was still in place. I chose to rely on the USGS and their figure of 2,600,000 km3.

    So now I could calculate the percentage of ice volume which survived the 20th century…
    The ice volume at the onset of the 20th century should be…

    2,600,000 km3 + 8,165 km3 = 2,608,165 km3

    Converting to percentage surviving the 20th century…

    2,600,000 km3 / 2,608,165 km3 = 0.997 = 99.7%


    To put the math into perspective, I’m going to actually rely on the SkepScibots



    1 gigatonne of ice is big… Much bigger than an Olympic sized swimming pool.

    So, throughout the 20th century, Greenland lost about 8,165 gigatonne ice cubes. 8,165 km3 equates to a 20 km x 20 km x 20 km cube of ice (3√ 8,165 = 20.136565). That would be one [email protected]$$ cube of ice!

    However, it’s not even a tiny nick when spread out over roughly 1.7 million square kilometers of ice surface. That works out a sheet of ice about 5 meters thick.

    2,600,000 km3 / 1,700,000 km2 = 1.53 km

    The average thickness of the Greenland ice sheet is approximately 1.5 km (1,500 meters). 5 meters is obviously 0.3% of 1,500 meters.



    Isopach map of Greenland ice sheet (Wikipedia). The “Lost Ice Cube” represents 8,165 cubic kilometers of ice.

    From a thickness perspective, 5 meters looks like this…



    Radar Cross Section of Greenland Ice Sheet (Source: Columbia University). Note that even with a vertical exaggeration of 75 x, 5 meters is insignificant.

    The red line along the top of the cross section is approximately 5 meters thick. Here is an enlarged view…



    While my math may not be exact, estimates of the volume of the Greenland ice sheet vary from 2.6 to 5.5 × 106 km3. The difference between 2.6 and 5.5 million cubic kilometers of ice is quite a bit larger than 9 trillion gigatonnes. For that matter, GRACE derived estimates of recent (2003-2011) ice mass balance vary widely as do the glacial isostatic adjustments…
    For the analyzed period, the ice mass balance of Greenland and the corresponding GIA correction are, respectively, − 256 ± 21 Gt yr−1 and − 3 ± 12 Gt yr−1 (1%) for SM09, − 253 ± 23 Gt yr−1 and − 6 ± 5 Gt yr−1 (2%) for AW13, and − 189 ± 27 Gt yr−1 and − 69 ± 19 Gt yr−1(36%) for Wu10 (table 1). At the regional scale, the ice mass estimates are more dependent on the GIA correction, especially in NE Greenland where the Wu10-GIA correction is the largest portion of the signal measured by GRACE (table 1).

    From Sutterley et al., 2014

    With ~±10% margins of error in modern satellite measurements of glacial mass balance and GIA accounting for up to 1/3 of the reported ice mass loss, it is truly amazing that a 0.3% reduction in the Greenland ice sheet during the 20th century can be identified with such robustness [/Sarc].

    http://wattsupwiththat.com/2015/12/3...-20th-century/
    Watts Up With That? | The world's most viewed site on global warming and climate change.

  • #2
    ^ Over fifty years later, after crash landing in July of 1942, the "Lost Squadron" was found under about 260+ feet of ice that had formed since then. To date, only the "Glacier Girl" has been recovered, still rather fascinating that if the ice of Greenland has been melting so much, here's a case where it didn't;
    http://p38assn.org/glaciergirl/index.htm

    Then there's the matter of the colonies of the Vikings from about a thousand years ago where it's still too cold to raise the crops and livestock they did back during that period of "global warming" ~
    TANSTAAFL = There Ain't No Such Thing As A Free Lunch

    Comment


    • #3
      This is the 21st century. Meanwhile, in the real world:
      Arctic temperatures in 2015 were the warmest on record, according to a report published on Tuesday that furthered concerns about the negative effects of melting sea ice.
      Temperatures in the Arctic were more than 2 degrees Fahrenheit warmer than average in 2015, according to the National Oceanic and Atmospheric Administration (NOAA) report. Some areas of the Arctic experienced temperatures more than 5 degrees warmer than average.
      “The Arctic is warming twice as fast as other parts of the planet,” NOAA chief scientist Rick Spinrad warned during a press conference on Tuesday.
      The higher-than-normal temperatures contributed to less sea ice in the Arctic, according to the report, compiled by some 70 authors from 11 countries.
      Minimum sea ice extent in September 2015 was 29 percent less than average, and was the fourth lowest in satellite record, the report said. Maximum sea ice extent occurred 15 days earlier than average, and was 7 percent less than average.
      The Chukchi Sea, northwest of Alaska, and Baffin Bay, off the west coast of Greenland, saw the largest warming trends, the report said.
      http://america.aljazeera.com/article...on-record.html

      Looks like more of Doc's junk science again.
      Last edited by Mountain Man; 30 Dec 15, 20:19.
      Quis Custodiet Ipsos Custodes? Who is watching the watchers?

      Comment


      • #4
        So the same trend of ice melt for the past 10,000 years continues...

        Yawn!!!
        Battles are dangerous affairs... Wang Hsi

        Comment


        • #5
          Yep...
          Quis Custodiet Ipsos Custodes? Who is watching the watchers?

          Comment


          • #6
            Originally posted by Pirate-Drakk View Post
            So the same trend of ice melt for the past 10,000 years continues...

            Yawn!!!

            The funny thing is that these two posts directly contradict each other:

            Originally posted by Mountain Man View Post
            This is the 21st century. Meanwhile, in the real world:http://america.aljazeera.com/article...on-record.html

            Looks like more of Doc's junk science again.
            Firstly, the Al Gore-zeerah article is abut sea ice, not Greenland's ice sheet.

            Secondly, "the record" only goes back ~150 years...
            Arctic temperatures in 2015 were the warmest on record, according to a report published on Tuesday that furthered concerns about the negative effects of melting sea ice.
            Temperatures in the Arctic were more than 2 degrees Fahrenheit warmer than average in 2015, according to the National Oceanic and Atmospheric Administration (NOAA) report. Some areas of the Arctic experienced temperatures more than 5 degrees warmer than average.
            “The Arctic is warming twice as fast as other parts of the planet,” NOAA chief scientist Rick Spinrad warned during a press conference on Tuesday.

            Thirdly, polar regions always warm and cool "twice as fast as other parts of the planet." Nothing the Arctic has done over the past 150 years is any different from what it was doing over the past 10,000 years. The Arctic has frequently been 1-2°C warmer that it currently is throughout the Holocene. It was ~5°C warmer during the previous interglacial stage (Sangamonian/Eemian).

            The Al Gore-zeerah article says that the recent warming is anomalous.

            Originally posted by Mountain Man View Post
            Yep...
            This proves that you neither read and understood my post or the Al Gore-zeerah article you posted.

            And irrespective of recent warming, Greenland had retained 99.7% of its ice mass since 1900.
            Last edited by The Doctor; 05 Jan 16, 05:30.
            Watts Up With That? | The world's most viewed site on global warming and climate change.

            Comment


            • #7
              Originally posted by G David Bock View Post
              ^ Over fifty years later, after crash landing in July of 1942, the "Lost Squadron" was found under about 260+ feet of ice that had formed since then. To date, only the "Glacier Girl" has been recovered, still rather fascinating that if the ice of Greenland has been melting so much, here's a case where it didn't;
              http://p38assn.org/glaciergirl/index.htm

              Then there's the matter of the colonies of the Vikings from about a thousand years ago where it's still too cold to raise the crops and livestock they did back during that period of "global warming" ~
              Another plane was located back in July of this year.
              P-38 Echo, flown by Lieutenant Colonel Robert Wilson.
              https://www.livescience.com/63423-lo...d-glacier.html
              Last edited by Persephone; 28 Oct 18, 18:17.
              "Stand for the flag ~ Kneel for the fallen"

              "A wise man can learn more from a foolish question than a fool can learn from a wise answer." ~ Bruce Lee

              Comment


              • #8
                Originally posted by G David Bock View Post
                ^ Over fifty years later, after crash landing in July of 1942, the "Lost Squadron" was found under about 260+ feet of ice that had formed since then. To date, only the "Glacier Girl" has been recovered, still rather fascinating that if the ice of Greenland has been melting so much, here's a case where it didn't;
                http://p38assn.org/glaciergirl/index.htm

                Then there's the matter of the colonies of the Vikings from about a thousand years ago where it's still too cold to raise the crops and livestock they did back during that period of "global warming" ~
                There are alt explanations for the farms....
                First itis a lot more economic to import grain and use the arable land In Greenland for veggie production for fresh local demand.

                The trout who swims against the current gets the most oxygen..

                Comment

                Latest Topics

                Collapse

                Working...
                X