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Robot Sub Finds Surprisingly Thick Antarctic Sea Ice

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  • #46
    Originally posted by Jedidiah View Post
    No need to talk dirty.
    My Tofu pigs hit the market next week.
    Glendower: I can call spirits from the vasty deep.
    Hotspur: Why, so can I, or so can any man;
    But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

    go with the flow the river knows . . .

    Frank

    I do not know, therefore everything is in pencil.

    Comment


    • #47
      Originally posted by shunyadragon View Post
      My Tofu pigs hit the market next week.
      Will they be paying with cash or credit?
      The first to state his case seems right until another comes and cross-examines him.

      Comment


      • #48
        Originally posted by Jedidiah View Post
        No need to talk dirty.
        What's with all the four letter words in this thread?

        Comment


        • #49
          Originally posted by sylas View Post
          ... it will take at least 1000 years after emissions stop for temperatures to start to fall. This isn't really controversial in the physical science of climate; it's reporting what's already well known to climate modelers.
          That's the point I think.

          I'd known that CO2 remains around in the atmosphere for 1,000 years and that's what makes it potentially worse than methane. While methane is a much more efficient green house gas, it remains in the atmosphere for a relatively short time.

          It had not really sunk in till I read your post, even though I had heard it often enough and understood it. There seems to be three aspects in operation here - hearing, understanding, and having it sink in. The first is easy, the second less so, and it requires the third (sinking in), for the actual importance of some idea to be appreciated in full.

          The other point you made elsewhere is also important. If the heat is not being radiated out into space, then it has to go somewhere. While there has been a "cooling" over the past years, it's been found that the oceans have been taking up that heat. So it's not as if atmospheric temperatures levelling off or dropping means that all is o.k., not if it's the oceans that have been picking up the heat instead.
          Last edited by rwatts; 11-26-2014, 02:41 PM.

          Comment


          • #50
            Originally posted by shunyadragon View Post
            I guess I did not totally explain myself. The long term warming trend I am talking about extends back ~18 to 20,000 years ago.

            http://www.geocraft.com/WVFossils/last_50k_yrs.html
            It's not so much that you did not explain yourself, so much as your position has no evidential support.

            I understand you, I think. I'm just bewildered as to why you are saying it; I did not expect it. The link doesn't help, because it doesn't support the notion of a long term warming trend at all.

            The graph at the link above does not show a warming trend extending from ~18 to 20,000 years up to the present; it rather shows the well known warming from out of the last glacial maximum up to the Holocene; and then the comparatively stable Holocene climate. There is no indication of that graph of any longer warming trend. Zilch. In that graph, the deglaciation warming ends about 10,000 years ago. This should not be news.

            A higher resolution and more careful look over the Holocene would indicate the much slower cooling trend since the Holocene Climate Optimum, which is actually what evidence indicates would still be at work in the absence of anthropogenic effects.

            The temperature graph on that page is the Vostok core deuterium temperature, as determined by Petit et al (1999) and plotted by the page author... and the rest of that website is outright pseudoscience with respect to climate. Not an encouraging source. But in any case, here's the data set the webpage uses: http://cdiac.ornl.gov/trends/temp/vostok/jouz_tem.htm

            Cheers -- sylas

            Comment


            • #51
              Originally posted by sylas View Post
              Shunya, I don't think that is actually true. On long scales, (omitting recent anthropogenic factors) we are on a long term COOLING trend. Of course, I'd welcome any clarification or reference to what you mean.

              My basic position is that the Holocene Thermal Maximum ended about 5000 years ago, and since then, Earth has been in a very slow decline of temperatures, with some shorter term untrended variations, and with lots of regional variations as well. But overall, on scales of 1000 years or more, Earth shows a slight but pretty definite cooling trend.

              Cheers -- sylas
              Since we all agree that the Earth's climate has never been static; which is ultimately more devastating to life on earth...another Little (or worse) Ice Age or the same degree of warming? Serious question...
              "What has the Church gained if it is popular, but there is no conviction, no repentance, no power?" - A.W. Tozer

              "... there are two parties in Washington, the stupid party and the evil party, who occasionally get together and do something both stupid and evil, and this is called bipartisanship." - Everett Dirksen

              Comment


              • #52
                Originally posted by Littlejoe View Post
                Since we all agree that the Earth's climate has never been static; which is ultimately more devastating to life on earth...another Little (or worse) Ice Age or the same degree of warming? Serious question...
                I honestly don't know; this question goes way outside the areas where I have a bit of background to consider.

                This is in no sense an answer, but here are three aspects of the question which make it a bit tricky, even if I did have the background to tackle it.

                1. Life in general is pretty resilient, and adapts to all kinds of changes. Adaptations do involve winners and losers, and periods of stress and recovery. But life in general takes in its stride whole ices ages, let alone a blip like the little ice age. Periods of unusual heat or drought also provide stress; and I would guess (it's only a guess) that which is worse depends very much on which species you consider. The economic impacts on humanity, for example, may be quite different from the impacts on life generally.

                2. The magnitudes of change in the Little Ice Age are uncertain (measuring climate in the past is hard) but involve about half a degree of drop globally from warmth in Medieval times to the coldest decades of the Little Ice Age. Local regions show greater differences, of course. This small level of change is not of great concern. It would be really nice if there was any prospect of the ongoing global warming being of a similar scale to the little ice age. Alas, that's not on the cards. So comparing the impact of the little ice are and a similar degree of increased temperature is entirely an academic exercise.

                3. Rate of change is crucial. Life, and humanity adapt much better to gradual changes rather than sudden ones. What makes modern climate change particularly stressful is not only the magnitude, but the speed at which it has occurred.

                Cheers -- sylas

                Comment


                • #53
                  Originally posted by sylas View Post
                  It's not so much that you did not explain yourself, so much as your position has no evidential support.

                  I understand you, I think. I'm just bewildered as to why you are saying it; I did not expect it. The link doesn't help, because it doesn't support the notion of a long term warming trend at all.

                  The graph at the link above does not show a warming trend extending from ~18 to 20,000 years up to the present; it rather shows the well known warming from out of the last glacial maximum up to the Holocene; and then the comparatively stable Holocene climate. There is no indication of that graph of any longer warming trend. Zilch. In that graph, the deglaciation warming ends about 10,000 years ago. This should not be news.

                  A higher resolution and more careful look over the Holocene would indicate the much slower cooling trend since the Holocene Climate Optimum, which is actually what evidence indicates would still be at work in the absence of anthropogenic effects.

                  The temperature graph on that page is the Vostok core deuterium temperature, as determined by Petit et al (1999) and plotted by the page author... and the rest of that website is outright pseudoscience with respect to climate. Not an encouraging source. But in any case, here's the data set the webpage uses: http://cdiac.ornl.gov/trends/temp/vostok/jouz_tem.htm

                  Cheers -- sylas
                  Let's clarify some things. I apologize for any miscommunication.

                  (1) I belief we are in a warming trend or climate change influenced by human activities. I am uncertain to what degree thus current trend is measurable specifically for human influence.

                  (2) I consider we are currently in a plateau at the apex of long term cycle ~100,000to 120,000, and not necessarily in the beginning of a cooling trend of that cycle. I believe your referenced graph http://cdiac.ornl.gov/trends/temp/vostok/jouz_tem.htm supports this, Something natural not human influence is delaying the cooling trend. Note in your reference graph previous cycles showed a sharp rise and an equally sharp decline in temperatures at the apex of the cycle, and this cycle doe not show that. I want make it clear I reference the graph information, and not the website's argument against the human influence on climate change. Like your Vostok graph, both indicate we are in the plateau before the cooling trend.

                  (3) Your argument that the Holocene Optimum is the apex of the cycle leading to the cooling trend is indirect, and may or may not be true. I believe the long term graphs show similar ups and downs in the temperature range over the long term plateau shown on the two graphs without the distinct beginning of a cooling trend.

                  (4) The problem with the range of overlapping of shorter term cycles and normal chaotic variation can complicate claims of how much influence humans have on climate change. We can enter a significant cooling trend, and still be under the influence of human impacts on climate change, and give the naysayers misleading support that humans do not influence the changes in the climate.

                  (5) I do believe the natural variations and trends are the stronger force in climate variation based on past trends and can be in and of themselves far more devastating then the human influence. Yes we should do what we can to reduce human influence (these efforts probably will have more influence on the quality of life, pollution, and human energy needs and use, then climate change.) , but because of the population growth trends in the third world and the demands for energy, the math is not there that we can change the trends of human influence significantly. Our efforts should be heavily into how we can deal with the potential of both natural and human climate changes.
                  Last edited by shunyadragon; 12-03-2014, 10:39 AM.
                  Glendower: I can call spirits from the vasty deep.
                  Hotspur: Why, so can I, or so can any man;
                  But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

                  go with the flow the river knows . . .

                  Frank

                  I do not know, therefore everything is in pencil.

                  Comment


                  • #54
                    This is quite long but it explains all you need to know about the rapidly approaching global catastrophe. Civilisation as we know it is about to end. Jesus is not coming to save us.
                    https://www.youtube.com/watch?v=m6pFDu7lLV4
                    “I think God, in creating man, somewhat overestimated his ability.” ― Oscar Wilde
                    “And if there were a God, I think it very unlikely that He would have such an uneasy vanity as to be offended by those who doubt His existence” ― Bertrand Russell
                    “not all there” - you know who you are

                    Comment


                    • #55
                      Originally posted by firstfloor View Post
                      This is quite long but it explains all you need to know about the rapidly approaching global catastrophe. Civilisation as we know it is about to end.
                      That happened after the invention of fire*, electricity and air conditioning, too.



                      *yes, I'm being facetious about the "invention" of fire.
                      The first to state his case seems right until another comes and cross-examines him.

                      Comment


                      • #56
                        Originally posted by firstfloor View Post
                        Jesus is not coming to save us.
                        Well, not ALL of us.
                        The first to state his case seems right until another comes and cross-examines him.

                        Comment


                        • #57
                          Originally posted by firstfloor View Post
                          This is quite long but it explains all you need to know about the rapidly approaching global catastrophe. Civilisation as we know it is about to end. Jesus is not coming to save us.
                          https://www.youtube.com/watch?v=m6pFDu7lLV4
                          That is the same line Chicken Little has been running around for quite some time. The problem is whether it is meaningful or simply an exercise in sarcasm pegging the needle in the ridiculous.
                          Glendower: I can call spirits from the vasty deep.
                          Hotspur: Why, so can I, or so can any man;
                          But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

                          go with the flow the river knows . . .

                          Frank

                          I do not know, therefore everything is in pencil.

                          Comment


                          • #58
                            Originally posted by Cow Poke View Post
                            That happened after the invention of fire*, electricity and air conditioning, too.
                            *yes, I'm being facetious about the "invention" of fire.
                            Global warming could make most of the planet uninhabitable by humans. Self inflicted extinction is a real possibility. The Bible might bring temporary comfort to a few but even these people know in their hearts that their hope is misplaced – “and the stars in the sky fell to earth, as figs drop from a fig tree when shaken by a strong wind.”

                            That is to say that it is obvious that the long dead writers of those ancient books had a radically different comprehension of the cosmos and for us to fawn over their literature and concepts, especially now that we see our predicament clearly, is disloyalty and even treason against the living.
                            Last edited by firstfloor; 12-04-2014, 03:51 AM.
                            “I think God, in creating man, somewhat overestimated his ability.” ― Oscar Wilde
                            “And if there were a God, I think it very unlikely that He would have such an uneasy vanity as to be offended by those who doubt His existence” ― Bertrand Russell
                            “not all there” - you know who you are

                            Comment


                            • #59
                              Originally posted by shunyadragon View Post
                              Let's clarify some things. I apologize for any miscommunication.
                              No problem; I do appreciate your approach.

                              I think we’ve resolved what was my initial point of surprise with mutual recognition that Earth’s climate is (absent human influences) in a plateau between glacial periods – the Holocene.

                              The Holocene is a nice comfortable plateau in between large temperature increases and decreases associated with the glacials (or ice ages). The graph certainly supports this.

                              Any trends within the Holocene are more subtle and should (and do) use more information than can be obtained from a single ice core. Even so, the Vostok core gives weak support to the conventional picture of a Holocene “Optimum” within the plateau, about 5000 years ago, and very slight trend of decline since then. There are, of course, substantial natural variations above and below the norm, like the MWP and LIA. Here’s a plot of the last 10000 years from the Vostok core data (cited previously) with a simple quadratic trend line fitted. This is not intended to be a strong argument of itself; for that I defer to more serious and detailed studies. Note this plot omits the preceding huge temperature shift in moving from the Ice Age glacial into the Holocene. [Added in edit... Horizontal scale is years before present, with "present" defined by convention to be 1950. The ice core cannot give data right up to the present; Vostok core data goes up to the year 1800 (or 150 years B.P.). In particular, the Vostok core cannot show any of the twentieth century warming. Vertical scale is in degrees. Petit et al uses a larger temperature shift per deuterium count than many researchers, so vertical scale may be as much as 50% too big in scale. This doesn't effect the shape of the curve, though.]
                              VostokCoreHoloceneTemperature.jpg
                              (3) Your argument that the Holocene Optimum is the apex of the cycle leading to the cooling trend is indirect, and may or may not be true. I believe the long term graphs show similar ups and downs in the temperature range over the long term plateau shown on the two graphs without the distinct beginning of a cooling trend.
                              I didn’t actually give an argument in this thread; that’s not really my area to argue in any detail. I rather referred to the conventional picture of the Holocene, without argument. Even the ice core plot above I’d hesitate to call an “argument”. The significance of the simple quadratic fit is really low; for the actual scientific case for the Holocene Optimum one can easily do a literature search. But it’s a fairly minor point, I think. My real point is that the trend of warming out of the last ice age is not something that is ongoing into the present.

                              The argument for or against a Holocene Optimum is no more direct or indirect than any inferences about temperature in the past. It’s all based on proxies. The difference is not that the evidence is indirect, but that the feature being identified does not stand out as dramatically as the ice ages.

                              All of this is pretty minor, and I consider my initial query to be resolved.

                              Thanks -- sylas
                              Last edited by sylas; 12-04-2014, 03:47 AM. Reason: comment on scale of graph

                              Comment


                              • #60
                                Originally posted by firstfloor View Post
                                Global warming
                                Oooooops... don't you mean "climate change"? Get with the program!
                                The first to state his case seems right until another comes and cross-examines him.

                                Comment

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