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  • Why not Global Warming?

    ...as a thread in the Barracks?

    So there was a thread in the Terrorism section called "Fight Global Warming like terrorism?" or some such. The discussion about the validity of Global Warming got pretty interesting (to me, anyway) and at some point, The Doctor wondered if the thread belonged in the Barracks. Well, I'm answering him by starting this thread, um, about 10 days too late.

    If you're sick of the discussion and want to go running in terror, be my guest. But I felt like I was learning something in the other thread, and, dammit, I wanna finish the discussion!

    Ok. So let's take this post by The Doctor as a starting point:

    Originally posted by The Doctor
    Methane is an extremely minor greenhouse gas - Even if it is far more efficient than CO2. Water vapor accounts for 60% of the greenhouse effect. CO2 accounts for about 20%; methane 7%; ozone 5% and other minor GHG's make up the remainder. But the greenhouse effect does not cause the Earth to warm. It enables the higher latitudes to retain more heat and be habitable. And there is not one single scrap of scientific evidence that suggests the increasing greenhouse gas concentrations have ever caused the Earth's climate to warm at any point in the last 600 million years.
    The reason I want to start here is because I think we can clear away some brush very quickly, and make sure there is at least "some" agreement on the fundamentals.

    So.

    1) The "greenhouse effect" is a very well understood phenomena that keeps the lower atmosphere at a temperature suitable for humanity. This is an indisputable scientific fact. Agree?

    2) Water Vapor is the primary gas associated with the greenhouse effect. This is an indisputable scientific fact. Agree?

    3) It is physically possible for the greenhouse effect to be intensified (E.g. if there were more water vapor in the lower atmosphere) such that the temperature of the lower atmosphere would be raised. This is indisputable scientific fact. Agree?

    4) The amount of C02 in the atmosphere has been steadily rising since the levels have been measured starting in 1958. (The so-called "Keeling Curve.") This is indisputable scientific fact. Agree?

    5) Ice cores are unreliable tools for determining the amount of C02 in the ancient atmosphere. Agree? (I don't think this is undisputable, but a recent study that debunks the "Gore" C02 hockey stick essentially debunks the entire notion of establishing ancient C02 concentrations by studying ice cores.)

    Now the $64,000 question: is there anything that can alter the greenhouse effect? Or, more to the point: can C02 alter it?

    According to The Doctor, there is no scientific evidence that C02 enhances the greenhouse effect. And yet, I thought it was Tyndall that established the relationship between C02 and the greenhouse effect to explain the onset of ice ages. And that a Swede used a mathematical formula to demonstrate what would happen to the temperature of Europe if the amount of C02 in the atmosphere were halved: (http://www.islandnet.com/~see/weathe...6/alm06feb.htm)

    Tyndall speculated fluctuations in water vapour and carbon dioxide could be related to climate change and the onset of ice ages. At century's end, Swedish scientist Svante Arrhenius applied Tyndall's discovery to the ice-ages riddle, mathematically showing that halving the atmosphere carbon dioxide concentration could lower European temperatures to an ice-age chill.
    So assuming that we have agreement on points 1-5 (a big assumption, I'll bet) then what's the controversy on Tyndall/Arrhenious' work?

    Tim
    "I just start kissing them. It's like a magnet. I just kiss. I don't even wait. You can do anything... Grab them by the [redacted]. You can do anything."
    -The President of the United States of America.

  • #2
    and you missed the first bit of the quote

    in 150ish years the CO2 concentrations have gone from 280ppm to 365ppm - an increase of ~30%

    in the same time methane concentrations have from 0.7ppm to 1.7ppm - an increase of ~140%

    considering that the global warming potential of the Methane is 12 times that of CO2, we see that that small amount of methane in the atmosphere accounts for ~20% of the total radiative forcing as shown by this diagram.



    now, considering that the icecore samples have shown that an increase in CO2 is usually companioned by an increase in CH4, and that the methane rate of increase has nearly quintupled that of CO2 since the onset of industrialisation, I find it very hard for someone to say that it's not an issue, or that its a natural cycle.

    ofc, there's no such thing as global warming you see, so we don't need to worry about it
    Last edited by Ivan Rapkinov; 18 Oct 07, 05:24.
    Now listening too;
    - Russell Robertson, ruining whatever credibility my football team once had.

    Comment


    • #3
      I read Al Gore's book and although I'm not an alarmist, I got warried about the future of the planet, but than again, maybe it's just the way that nature works. If we are to believe in what the books tell us, the Sahara was a tropical forest and became a desert long before Men had any impact in the planet. That's just to mention one example.
      All warfare is based on deception.
      Sun Tzu - Art of war - Chapter One - Laying Plans


      Comment


      • #4
        Originally posted by Ivan Rapkinov View Post
        and you missed the first bit of the quote

        in 150ish years the CO2 concentrations have gone from 280ppm to 365ppm - an increase of ~30%

        in the same time methane concentrations have from 0.7ppm to 1.7ppm - an increase of ~140%

        considering that the global warming potential of the Methane is 12 times that of CO2, we see that that small amount of methane in the atmosphere accounts for ~20% of the total radiative forcing as shown by this diagram.



        now, considering that the icecore samples have shown that an increase in CO2 is usually companioned by an increase in CH4, and that the methane rate of increase has nearly quintupled that of methane since the onset of industrialisation, I find it very hard for someone to say that it's not an issue, or that its a natural cycle.

        ofc, there's no such thing as global warming you see, so we don't need to worry about it
        Some questions:

        How does methane act as a greenhouse gas?

        What exactly is meant when we say that methane has 12 times global warming potential?

        How did the ice core samples show that there had been a quintipled rate of increase since the industrialisation age?

        How do we know that any increase of CO2 or methane in the atmosphere - assuming that there had indeed been an increase - was due to industrial activity?

        Thanks.
        Last edited by Ogukuo72; 18 Oct 07, 04:27.

        Comment


        • #5
          Originally posted by Ogukuo72 View Post
          Some questions:

          How does methane act as a greenhouse gas?
          the same way CO2, Ozone and Water does. It increases the "absorption" of infrared radiation that would otherwise be transmitted through the atmosphere and into space. More heat in the upper atmosphere relates to hotter on the surface due to convection.

          as to why these things are infrared absorbers, that's getting into irritating things like quantumn mechanics - if you're really keen, I can explain it but it's a very accepted thing.

          What exactly is meant when we say that methane has 12 times global warming potential?
          Global warming potentials (GWPs) are used to compare the abilities of different greenhouse gases to trap heat in the atmosphere. GWPs are based on the radiative efficiency (heat-absorbing ability) of each gas relative to that of carbon dioxide (CO2), as well as the decay rate of each gas (the amount removed from the atmosphere over a given number of years) relative to that of CO2.



          I say 12 times the GWP of CO2, because Methane has a lifetime of 12 years, and the most of the calculations are based over differing time periods. This one has it at 21 times that of CO2 (over a period of 100 years), but say over a 500yr period, the GWP of CH4 is only 7 times that of CO2. Likewise, over a 20 year period CH4 is ~60 times that of CO2.

          Though to be honest, I picked up my numbers from an ANSTO (Australian Nuclear Science and Tech Organisation) research paper on the subject. Rather than doing all the numbers myself, I went with their 12 times figure.

          How did the ice core samples show that there had been a quintipled rate of increase since the industrialisation age?
          140% increase almost = 5x 30% increase....

          How do we know that any increase of CO2 or methane in the atmosphere - assuming that there had indeed been an increase - was due to industrial activity?
          because the onset of industrialisation is stated at about 1850, and that's the time period over which the increases mentioned were measured - note I didn't say anything about the CO2 increase - it might be natural, I doubt it, but it might be. But the methane rate of increase should be similar to that of the CO2, not non-proportionately higher.

          should also point out according to the IPCC, the increase in CH4 has an indirect effect on the amount of stratospheric water vapour - further adding to the radiative forcing.
          Last edited by Ivan Rapkinov; 18 Oct 07, 06:20.
          Now listening too;
          - Russell Robertson, ruining whatever credibility my football team once had.

          Comment


          • #6
            watch 20/20 friday night at 5 pm pacific time

            There will be a discussion on 20/20 friday night.

            http://www.newsmax.com/insidecover/g.../17/41855.html


            The thing to check is the phases of the sun. No one talks about Mars warming up enough to start melting ice. Or one of the moons of Saturn. Last time I checked, the human race is not on Mars.


            Oh, and everyone needs to stop passing gas.

            Comment


            • #7
              Originally posted by armor11 View Post
              ...as a thread in the Barracks?

              So there was a thread in the Terrorism section called "Fight Global Warming like terrorism?" or some such. The discussion about the validity of Global Warming got pretty interesting (to me, anyway) and at some point, The Doctor wondered if the thread belonged in the Barracks. Well, I'm answering him by starting this thread, um, about 10 days too late.

              If you're sick of the discussion and want to go running in terror, be my guest. But I felt like I was learning something in the other thread, and, dammit, I wanna finish the discussion!

              Ok. So let's take this post by The Doctor as a starting point:



              The reason I want to start here is because I think we can clear away some brush very quickly, and make sure there is at least "some" agreement on the fundamentals.

              So.

              1) The "greenhouse effect" is a very well understood phenomena that keeps the lower atmosphere at a temperature suitable for humanity. This is an indisputable scientific fact. Agree?
              Correct. Without the greenhouse effect, only the tropics would be habitable.

              2) Water Vapor is the primary gas associated with the greenhouse effect. This is an indisputable scientific fact. Agree?
              Correct.

              3) It is physically possible for the greenhouse effect to be intensified (E.g. if there were more water vapor in the lower atmosphere) such that the temperature of the lower atmosphere would be raised. This is indisputable scientific fact. Agree?
              The greenhouse effect is one of diminishing returns. It is not a linear function. A doubling of greenhouse gasses does not double the greenhouse effect.

              4) The amount of C02 in the atmosphere has been steadily rising since the levels have been measured starting in 1958. (The so-called "Keeling Curve.") This is indisputable scientific fact. Agree?
              The only direct measurements started in 1958. Ice core data suggest that CO2 had increased from 290ppm to 310ppm from 1880 to 1958. From 1958 to 2006 it increased from 310ppm to 385ppm.

              This is not a strong correlation...
              From 1908 to 1942, the Earth warmed about 1 degree F while CO2 increased about 10ppm.

              From 1942 to 1977, the Earth cooled about 0.6 F while CO2 increased about 25ppm.

              From 1977 to 1998, the Earth warmed about 1.1 F while CO2 increased about 70ppm.



              5) Ice cores are unreliable tools for determining the amount of C02 in the ancient atmosphere. Agree? (I don't think this is undisputable, but a recent study that debunks the "Gore" C02 hockey stick essentially debunks the entire notion of establishing ancient C02 concentrations by studying ice cores.)
              That is false. Ice cores may not provide absolute CO2 numbers; but they are very reliable indicators of relative changes.

              In every glacial cycle recorded in the Vostok ice core, the temperature changes preceded the greenhouse gas changes by an average of 800 years. This proves that greenhouse gasses did not drive Pleistocene climate changes and it is evidence that temperature changes might caused changes in atmospheric greenhouse gas concentrations.

              Now the $64,000 question: is there anything that can alter the greenhouse effect? Or, more to the point: can C02 alter it?
              Sure it can. It just requires a geometrically increasing about of CO2 to increase the greenhouse effect in a geometrically diminishing manner.

              If changes of 100ppm CO2 could drive temperature changes; then 1000ppm changes would have caused even more changes - But there is no evidence that they ever have. Furthermore, if CO2 drives temperature changes, we should be far warmer now than we were during the Pleistocene interglacials...But we are actually cooler...




              According to The Doctor, there is no scientific evidence that C02 enhances the greenhouse effect. And yet, I thought it was Tyndall that established the relationship between C02 and the greenhouse effect to explain the onset of ice ages. And that a Swede used a mathematical formula to demonstrate what would happen to the temperature of Europe if the amount of C02 in the atmosphere were halved: (http://www.islandnet.com/~see/weathe...6/alm06feb.htm)
              I never said that "there is no scientific evidence that C02 enhances the greenhouse effect." I said that there is no evidence of greenhouse gasses ever driving climate change.

              So assuming that we have agreement on points 1-5 (a big assumption, I'll bet) then what's the controversy on Tyndall/Arrhenious' work?

              Tim
              I have no problem with Tyndall/Arrhenious' work. But their theory doesn't establish causality. The Pleistocene ice cores specifically disprove causality.

              If CO2 and other greenhouse gasses (as trace components in our Nitrogen-Oxygen atmosphere) could cause climate change, there would be compelling evidence for it in the geological record...But there is no such evidence.

              There's no long term correlation...



              The Pleistocene provides a reverse short term correlation and no correlation since the Holocene...



              And two of the four most recent millennial reconstructions covering the show the modern warming to be remarkably similar to the Medieval Warming...


              Hegerl's work did not extend back to the MWP.

              Mann's "Hockey Stick", has been discarded even by the IPCC and demonstrated to be at the very best statistically flawed and at the worst to be patently fraudulent…So there is no evidence that the modern warming is either anomalous in nature or anthropogenic in sourcing. There is also no evidence that Kyoto (or a dozen Kyotos) can alter the process.
              Last edited by The Doctor; 18 Oct 07, 10:27.
              Watts Up With That? | The world's most viewed site on global warming and climate change.

              Comment


              • #8
                Originally posted by The Doctor View Post
                That is false. Ice cores may not provide absolute CO2 numbers; but they are very reliable indicators of relative changes.
                Ok. I was thinking of this guy:

                Originally posted by Armor11 from the other thread
                This guy (Dr. Zbigniew Jaworowski ) debunks the whole notion of how much C02 was supposedly in the "Pre-industrial" atmosphere. He does so by invalidating ice cores as a method for estimating atmospheric C02. This invalidates a fundamental tenent of Goreian global warming: that C02 concentrations have increased dramatically in the industrial age.

                From http://www.warwickhughes.com/icecore/
                But it would appear that there is significant controversy over his conclusions, some outlined here: http://www.someareboojums.org/blog/?p=7

                So we'll just assume that the "ice core science" works. Good.

                In every glacial cycle recorded in the Vostok ice core, the temperature changes preceded the greenhouse gas changes by an average of 800 years. This proves that greenhouse gasses did not drive Pleistocene climate changes and it is evidence that temperature changes might caused changes in atmospheric greenhouse gas concentrations.
                This is part of the "normal" feedback loop, right? As the temperature of the atmosphere rises (from whatever cause), it can hold more greenhouse gas.

                Originally posted by The Doctor
                From 1908 to 1942, the Earth warmed about 1 degree F while CO2 increased about 10ppm.

                From 1942 to 1977, the Earth cooled about 0.6 F while CO2 increased about 25ppm.

                From 1977 to 1998, the Earth warmed about 1.1 F while CO2 increased about 70ppm.
                Well, those are interesting dates you pick there. I don't think you can pull 25 year ranges out of the graph and expect to derive a significant trend.

                But look at the WHOLE graph.

                Doesn't that line strongly correlate temperature and C02?

                Doesn't that temperature increase fit the model (based on physics) of what the impact of C02 concentrations are supposed to have on temperature?

                From http://earthguide.ucsd.edu/globalcha...arming/03.html

                The overall rise is from just below 280 ppm (the �pre-industrial� value) to the present values above 360 ppm, an increase of a factor of 1.3. The logarithm of 1.3 is 0.11, that of 2 is 0.30. Thus, we are a little more than one third of the way to a doubling of carbon dioxide, on a log scale. If doubling of carbon dioxide produces a temperature rise of between 1.5 and 5 degrees Celsius (as found in numerical experiments using climate models), we should see a warming of between 0.5 and 1.7 degrees Celsius. We do see the lower number of this range, but this does not prove that the rise upon doubling of carbon dioxide is in fact 1.5 degrees. The reason is that we are in a �transient�, that is, the change is too fast to allow equilibrium to establish itself.

                In fact, the answer is not known with a high degree of certainty, not only because of the lack-of-equlibrium problem (which involves uptake of heat by the ocean), but also because of additional complexities arising from air pollution, trace gases other than carbon dioxide, possible changes in the possible changes in the brightness of the Sun, and effects from volcanic activity.
                Originally posted by The Doctor
                If CO2 and other greenhouse gasses (as trace components in our Nitrogen-Oxygen atmosphere) could cause climate change, there would be compelling evidence for it in the geological record...But there is no such evidence.
                But we know greenhouse gas CAN cause climate change because that's just physics. It's the greenhouse gas that provides the "climate change" that makes life palatable, right?

                I'm not discounting the lack of causality here, I'm merely discussing what we know about the physical chemistry of greenhouse gas and it's effect on the temperature of the lower atmosphere.

                We'll get back to the ice core data in a minute...I just want to be sure I understand this point.

                Tim
                "I just start kissing them. It's like a magnet. I just kiss. I don't even wait. You can do anything... Grab them by the [redacted]. You can do anything."
                -The President of the United States of America.

                Comment


                • #9
                  Originally posted by armor11 View Post
                  Ok. I was thinking of this guy:



                  But it would appear that there is significant controversy over his conclusions, some outlined here: http://www.someareboojums.org/blog/?p=7

                  So we'll just assume that the "ice core science" works. Good.
                  And the ice core science shows no evidence that greenhouse gasses caused any of the Pleistocene glacial cycles.

                  Originally posted by armor11
                  This is part of the "normal" feedback loop, right? As the temperature of the atmosphere rises (from whatever cause), it can hold more greenhouse gas.
                  Warmer oceans can hold less CO2 in solution. A warming Earth leads to more biological activity and more CO2 and CH4. A warming Earth produces more atmospheric CO2 and CH4 and the oceans have less capacity as carbon sinks. There's no observational of analogical evidence that the anthropogenic GHG emissions over the past 150 years have altered the Earth's natural climate cycles. The Earth is no warmer than it was during the Medieval Warm Period; nor has it warmed any faster than it did at the beginning of the MWP. The Earth is actually cooler than it was during the previous four Pleistocene interglacials - despite having significantly higher GHG concentrations.

                  Originally posted by armor11
                  Well, those are interesting dates you pick there. I don't think you can pull 25 year ranges out of the graph and expect to derive a significant trend.
                  1908-1942 was a warming trend; 1942 to 1977 was a cooling trend; and 1977 to 1998 was a warming trend.
                  But look at the WHOLE graph.

                  Doesn't that line strongly correlate temperature and C02?
                  It only appears to correlate in the 1977 to 1998 warming trend. However, if the graph used the same scale as the ice core graph, there would be no correlation at all in the post-Holocene.

                  Originally posted by armor11
                  Doesn't that temperature increase fit the model (based on physics) of what the impact of C02 concentrations are supposed to have on temperature?

                  From http://earthguide.ucsd.edu/globalcha...arming/03.html
                  Only when the scales of the curves are adjusted to make them appear that way.



                  Originally posted by armor11
                  But we know greenhouse gas CAN cause climate change because that's just physics. It's the greenhouse gas that provides the "climate change" that makes life palatable, right?
                  We theorize that the Earth's greenhouse gasses insulate the Earth and make the upper latitudes habitable...And it is a very sound scientific theory. However, there is no evidence at any point in the last 600 million years that greenhouse gas concentrations have ever caused climate change.

                  Originally posted by armor11
                  I'm not discounting the lack of causality here, I'm merely discussing what we know about the physical chemistry of greenhouse gas and it's effect on the temperature of the lower atmosphere.

                  We'll get back to the ice core data in a minute...I just want to be sure I understand this point.

                  Tim
                  If you think that tinkering with atmospheric CO2 concentrations can substantially alter the Earth's climate, you are discounting causality.
                  Last edited by The Doctor; 19 Oct 07, 08:23.
                  Watts Up With That? | The world's most viewed site on global warming and climate change.

                  Comment


                  • #10
                    Originally posted by Ivan Rapkinov View Post
                    the same way CO2, Ozone and Water does. It increases the "absorption" of infrared radiation that would otherwise be transmitted through the atmosphere and into space. More heat in the upper atmosphere relates to hotter on the surface due to convection.

                    as to why these things are infrared absorbers, that's getting into irritating things like quantumn mechanics - if you're really keen, I can explain it but it's a very accepted thing.
                    If you could send me the link I can read it myself. I've never heard anyone explain to me just how it actually works. They just tell me that CO2, water vapour etc. 'bounces back' the heat, but didn't explain how.



                    Global warming potentials (GWPs) are used to compare the abilities of different greenhouse gases to trap heat in the atmosphere. GWPs are based on the radiative efficiency (heat-absorbing ability) of each gas relative to that of carbon dioxide (CO2), as well as the decay rate of each gas (the amount removed from the atmosphere over a given number of years) relative to that of CO2.
                    I didn't know that gases like CO2 and water vapor have decay rates - I thought it only related to radioactive material. I know O3 is unstable, but I didn't know that it could also decay. Do you have further information on this or point me to the link? Thanks.

                    BTW, how do they measure how one gas has more ability to trap heat than another?

                    because the onset of industrialisation is stated at about 1850, and that's the time period over which the increases mentioned were measured - note I didn't say anything about the CO2 increase - it might be natural, I doubt it, but it might be. But the methane rate of increase should be similar to that of the CO2, not non-proportionately higher.
                    The issue I would have is that correlation did not necessarily mean causation. As you pointed out, it could very well be natural and coincidental. But it's a point that we probably can't settle at the moment.

                    If methane increase at the same rate as the CO2, that seem to imply something natural was taking place. I know of no process by which methane could produce more CO2 or vice versa.

                    Thanks.

                    Comment


                    • #11
                      Water vapor, methane, carbon dioxide and other greenhouse gasses are essentially transparent to incoming full-band-width solar radiation; however they are generally opaque to infrared radiation.

                      Incoming solar radiation warms the atmosphere and the surface of the Earth. The warming surface reflects some infrared radiation. A portion of the reflected infrared radiation is re-radiated back to the surface by greenhouse gasses.

                      It's not really a "decay rate"; atmospheric CO2 is eventually taken up by plants, the oceans and other carbon sinks. Atmospheric CH4 (methane) eventually oxidizes to form CO2 and water vapor over an 8 to 12 year period.

                      CO2 is a natural byproduct of CH4 oxidation. When we burn natural gas (Methane, propane, etc.) we produce CO2 and water. When methane naturally oxidizes it produces CO2 and water.

                      CO2 and CH4 are important trace compounds in the atmosphere. Without them, life might not be able to exist. However, the Earth's average temperature since the Cambrian period has generally hovered around 22 C (72 F) during non-Ice Ages. During Ice Ages it drops to around 12 C (54 F), irrespective of greenhouse gas concentrations. We are currently in a warming cycle within an interglacial period of an Ice Age.

                      The Earth has experienced Ice Ages about every 135 million years. The Ice Ages correlate most closely with our solar system's movements through the Milky Way Galaxy; occurring when we move through the bright spiral arms. It is possible that during these periods, the influx of cosmic radiation over-powers the solar wind. The radiation's ionizing effect on the atmosphere creates more cloud cover and causes rapid cooling.

                      Within the current Ice Age, the Earth undergoes cycles of enhanced cooling and continental glaciation about every 130,000 years. These cycles correlate very well with the Milankovich cycles - slight changes in the Earth's rotation, axis and orbital mechanics.

                      Within the current interglacial period, the Earth undergoes a roughly 1500 year cycle of warming and cooling. The Dansgaard-Oeschger events are a series of rapid climate oscillations with a frequency of about 1470 years. The most recent phases of the Dansgaard-Oeschger cycle are the Medieval Warming Period, the Little Ice Age and the Modern Warming. The Modern Warming began after the Little Ice Age in the mid-1800s. The modern warming is no warmer than the Medieval Warm Period; nor did it come on any faster. The 1500 year cycle closely correlates with a convolution of the 87 year and 210 year solar activity cycles.

                      Within the Modern Warming, the Earth has undergone two warming (1908-1942 and 1977-1998) cycles and one cooling cycle (1942-1977). These cycles correlate very closely with the frequency of the 11 year sunspot cycle. When the cycle shortens, the Earth warms. When it lengthens, the Earth cools.

                      During the 1908-1942 warming, the Earth’s CO2 levels increased by 10 ppm and the Earth warmed about 1 F. During the 1942-1977 cooling, the Earth’s CO2 levels rose by 25 ppm and temperatures declined by 0.6 F. During the 1977-1998 warming, CO2 levels rose by 75 ppm and temperatures rose 1.1 F. Since 1998, the Earth has cooled by about 0.1 to 0.2 F, while CO2 levels have continued to rise.

                      The solar cycles are not necessarily indicative of the Sun's radiative heating of the Earth. It is more likely that increased solar activity increases to solar wind and blocks out more cosmic radiation, reducing cloud cover, and allowing more solar warming.
                      Last edited by The Doctor; 19 Oct 07, 10:02.
                      Watts Up With That? | The world's most viewed site on global warming and climate change.

                      Comment


                      • #12
                        Ogukuo72: Doc explained it better and more succinctly than I could

                        as for how they measure the "heat trapping" ability of each gas, even though I'm loathe to use it, wiki is the best at simply explaining them

                        http://en.wikipedia.org/wiki/Global_warming_potential

                        and here's a DOE one that goes into further detail
                        http://www.eia.doe.gov/oiaf/1605/gwp.html

                        If methane increase at the same rate as the CO2, that seem to imply something natural was taking place. I know of no process by which methane could produce more CO2 or vice versa.
                        Indeed, which is why the increase in methane compared to that of CO2 is so surprising. As CO2 is a byproduct of CH4 as it breaksdown, we should be seeing a commeasurate increase in the CO2 levels with the increasing methane. That we're not means more CH4 is being pumped into the atmosphere than should be. The fact it affects stratospheric water vapour (remembering that water vapour is a another infrared absorber) as well, means that increase of Methane has a bigger flow on effect than it;s small concentration first suggests.
                        Now listening too;
                        - Russell Robertson, ruining whatever credibility my football team once had.

                        Comment


                        • #13
                          Originally posted by The Doctor View Post
                          If you think that tinkering with atmospheric CO2 concentrations can substantially alter the Earth's climate, you are discounting causality.
                          Hold on a second here.

                          This is physics, not opinion, right?

                          Many things can affect climate *besides* C02 concentrations, right?

                          In other words, I don't think anyone is saying (besides Al Gore, I suppose) that tinkering with C02 concentrations is GUARANTEED to induce climate change regardless of circumstances. E.g. If a large meteorite/comet were to slam into the Earth, it might have some kind of impact on the greenhouse effect. Or if the Earth were to wobble slightly on it's axis, or if solar activity were to increase, or whatever. There are plenty of things that might diminish (or enhance) the greenhouse effect, right?

                          But, (everyone I know has a big butt!), what would happen if the concentration of C02 were to double or quadruple TODAY? (By TODAY I mean within the next 30 years or so?)

                          If we look at your graph of the "Galatial-Interglatial Ice Core Data," C02 concentrations have never approached their current levels within the last 600 thousand years, correct? But the graph indicating C02 concentrations from 600 million years ago shows a TON of C02 in the air without any appreciable effect on temperature. I have no idea what other factors (tilt of Earth's axis, amount of vegetation, cloud cover, etc) may have been in place 600 million years ago, after all that was the period during a global ice age, but I'll wager the conditions (things that can affect climate BESIDES greenhouse gas), are pretty indeterminate.

                          The "Pre-industrial" high levels were right around 280, while the current level is about 360. (Of course, C02 isn't the ONLY greenhouse gas, as Ivan pointed out, so high concentrations of Methane also need to be considered.) What if it hit 720? i.e. Isn't the modeling for the effect of climate change based on well understood properties of our current atmospheric conditions? (There is still a lot of uncertainty in the models. I understand that.)

                          Incidentally, I suppose the Ice Core data graph that you posted (going back 700 hundred thousand years doesn't have the appropriate level of granularity), but it sure does look like there is a temperature spike accompanying a rise in C02 and Methane. But the graph is pretty confusing to a guy with my IQ, so maybe I'm reading it wrong. (I think this is the graph that you use to indicate that the rise in greenhouse gas FOLLOWS a temperature rise, instead of the converse. So I guess the actual numbers clarify those spikes.)

                          Tim
                          "I just start kissing them. It's like a magnet. I just kiss. I don't even wait. You can do anything... Grab them by the [redacted]. You can do anything."
                          -The President of the United States of America.

                          Comment


                          • #14
                            The Vostok ice core data do show a correlation between temperature and CO2 (and other GHGs). The problem for the greenhouse driven theory is that the temperature changes were followed by the CO2 changes, by an average of 800 years.

                            What would happen if CO2 levels doubled in a short time (~30 years)?

                            Assuming all other factors were static, a doubling of CO2 could cause the Earth to warm an additional 0.7 C...



                            That is a theoretical possibility. However, no matter how much CO2 levels rise, the most warming they can cause is an additional 0.9 C.

                            CO2 just can't move the temperature that much. Furthermore, CO2 is just a small part of many factors that are simultaneously influencing the climate to warm and cool in different places at different rates.

                            Assuming that the greenhouse theory was exactly right...it can only nudge the natural solar-driven climate cycles a little bit one way or the other.

                            Mankind only accounts for about 3% of the Earth's carbon budget. While it is possible that all of the CO2 increase from 280 ppm to 380 ppm was anthropogenic, it's doubtful.

                            Without the greenhouse effect, the global average surface temperature would be 33 C lower than it is. CO2 accounts for 20% of the greenhouse effect (6.6 C). Mankind contributes 3% of the carbon budget. If we stopped emitting all CO2 tomorrow, the absolute most that we could accomplish is to lower the average surface temperature 0.2 C. Since we don't know how long it will take the oceans and other carbon sinks to process the 100 ppm of CO2 that we may have contributed over the past century, we can't even begin to predict whether any additional cooling might ensue.

                            So for us to significantly reduce the very minor greenhouse warming that might be the result of anthropogenic CO2 emissions, we would essentially have to stop emitting any CO2...at the cost of bankrupting western civilization and killing a couple of billion people.

                            So when we combine the very small impact that anthropogenic CO2 might be having on the climate and combine it with the gargantuan cost of rapid remediation...the cost-benefit analysis doesn't look good. Then when we view the mathematical models and theories that support the notion of anthropogenic global from the perspective of observational and analogical data from the dawn of the Phanerozoic to 1977...it's hard to take the climate models seriously.
                            Watts Up With That? | The world's most viewed site on global warming and climate change.

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                            • #15
                              Originally posted by The Doctor View Post
                              Assuming all other factors were static, a doubling of CO2 could cause the Earth to warm an additional 0.7 C...
                              So that's C02, and that's an additional .7. So the total might be 1.3 from the 1800's to the 2100's. Call it a worse case scenario for C02. And of course that temperature scale is in centigrade, so in degrees Fahrenheit we've already warmed 1 degree. 1.7 C is actually 2 or 3 degrees Fahrenheit. Which doesn't really matter, I suppose, if that amount of change has no appreciable effect on our quality of life. Is that true?

                              Now, C02 isn't the only greenhouse gas.

                              What effect would doubling the amount of Methane (and other greenhouse gas) in the atmosphere have if you are also doubling the amount of C02?

                              Any guesses?

                              In a "worst case scenario" (taking ALL greenhouse gas into consideration) are we talking 2 or 3 degrees C increase over the next 30 years or so? If so, is that a cause for concern?

                              Tim
                              "I just start kissing them. It's like a magnet. I just kiss. I don't even wait. You can do anything... Grab them by the [redacted]. You can do anything."
                              -The President of the United States of America.

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