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please explain this

Discussion in 'Environmental Discussion' started by Former Member 68813, Jul 17, 2015.

  1. Former Member 68813

    Former Member 68813 Senior Member

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    here is the fallacy of this statement:
    most of the warming from the minimum of the last glaciation (technically we are still in the ice age, believe it or not) was caused by Milankovitch cycle (aided by increased CO2 of course and even more so by the forgotten water vapors). if the sun radiation is in the decreasing part of the cycle (as i understand is the consensus), doubling of CO2 will not have the same effects, especially since we don't know all the negative feedbacks of increased CO2.
     
  2. austingreen

    austingreen Senior Member

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    If you look at my post in the thread directly that was replied to here, you will note that I said solar radiation (simple magnitude) which is what changes with the ice age cycle should also be plotted.

    The 2.8 number is alley's correlation of log base 2 of the doubling of carbon dioxide equivalent ghg concentration. If we are driven by cycles in the earths orbit that increases and decreases radiation the ghg concentration should lag. Correlation is not causation, and all a chart can show is correlation. In certain places in the chart ghg leads the temperature. It is here that we can look at what seems to be positive feedback, but there is quite a bit of uncertainty.

    It should be obvious that there is positive and negative feedback, and we have a theory of tipping points, so the sensitivity number, the net result of positive and negative feedback and tipping points only related to ghg not temperature, is difficult to determine right now and is a range.

    We can look at various mechanisms of the positive and negative feedback and natural variation, and conduct experiments to see if they are correct. Nasa is currently experimenting to determine if these are correct, and It is my hope in 20 or 30 years our understanding is fairly complete, but it takes a long time to do these climate experiments/observations.

    No descent climate scientist ignores the milankovitch cycles, but this cycle has had very little effect if we only look at the last 150 years as solar radiation and the earths orbit has been fairly stable. There are sun spot cycles (around 11 years for a half cycle) and we may soon be able to measure the effects of low sun spot count, and answer some questions about climate variation relating to solar cycles. Here there is still dispute.
     
  3. FL_Prius_Driver

    FL_Prius_Driver Senior Member

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    But we know all the positive feedback effects of increased CO2?

    There is a difference between knowing the future (we don't) and running an uncontrolled experiment based on assuming a future.
     
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  4. Former Member 68813

    Former Member 68813 Senior Member

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    we do know that the rapid rise of CO2 in the previous interglacial warmings was rapidly reversed, so there are clearly strong negative feedbacks in play. if (as you postulate) positive feedbacks were more important, the previous rises of CO2 would end up in runaway temperature events. that clearly didn't happen in the glacial/interglacial cycles or even older vulcanic episodes of CO2 spikes. those CO2 spikes were always short lived.
     
  5. FL_Prius_Driver

    FL_Prius_Driver Senior Member

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    Presently, humans are in the process of making this CO2 concentration elevation a permanent change, not a spike. Whatever feedback mechanism reduced CO2, we are overriding it right now.
     
  6. austingreen

    austingreen Senior Member

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    That is positive feedback on temperature. Temperature drops, earth sequesters more carbon dioxide, carbon dioxide reduces ghg warming, temperature drops a little more.

    The dominant mechanism of the ice age cycle is radiation changes which trigure positive feedbacks in both temperature and greenhouse gasses.

    To begin ice age -> reduced radiation -> lower termperature -> lower green house gasses->more ice and reflected radiation and less heat trapped by green house gasses.

    To being interglacial -> increased radiation -> higher temperature->higher ghg->less ice, less reflected radiation and more heat trapped by green house gasses.

    The question is when the temperature change lags the green house gas change how much feedback there will be. There is both negative and positive feedback mechanisms, but the main naritive is possitive feedback.
     
  7. tochatihu

    tochatihu Senior Member

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    Austin, Bob and Jacek all advocate the use of logs. So use them freely in your graphics, over one dissenting vote.


    The reason that every doubling absorbs the same? Really this could be ‘on the exam’.


    Imagine a tube containing the chosen gas, with light coming in at one end. The concentration of that gas inside is the same everywhere. In the first quarter (let us say) of the tube, 10% of the light is absorbed. The second quarter of the tube contains the same amount of gas as the first, but less light arrives. Of that, again, 10% of the remaining light is absorbed. Same all the way down the line. That ‘remaining’ is an important point. Gas does not absorb XX watts of light energy. It absorbs YY fraction of however many watts that are passing through. That’s why doubling (or tripling, or any other ‘folding’ behave the same.


    And that’s why logarithms, which are ‘how many times you multiply by the same number’, fill the bill. And if each in your audience understands that thoroughly, it won’t lead to questions and you can stay on your main point, whatever it might be. Exponential decay is completely analogous; ‘how many times you divide by the same number’ but I stop here.
     
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  8. tochatihu

    tochatihu Senior Member

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  9. tochatihu

    tochatihu Senior Member

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    forgotten water vapors@121. Well they aren't forgotten, and your belief to the contrary simply stands as a monument (of some sort).

    If you could describe a mechanism to increase atmospheric water vapor other than the ones we have already discussed, I'd much appreciate it.
     
  10. austingreen

    austingreen Senior Member

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    I posted alley's video, but that takes 40 minutes to explain all this stuff - ice ages, radiation, green house gases, etc. I agree my short post was inadequate. If you have a better explanation video it would be great. Perhaps we can get neil tyson to do one, as more people like watching him then the typical professor's lecture. I hope you explaination of log works for the OP. For me the log works perfectly without feedback. With feedback we need to examine each, which is what makes it so tough. I believe even Linzden believes its net possitive, but he thinks it is small, others belive it is larger than 4, but there have been some papers suggesting if it was much larger than 4 we would have had more ice ages.
     
    #130 austingreen, Jul 31, 2015
    Last edited: Jul 31, 2015
  11. tochatihu

    tochatihu Senior Member

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    Ice-age Denial was a big thing until overwhelmed by evidence about 1850. There was simply no money to be made by holding back. This is different now; tons of money from burning fossils, so evidence does not overwhelm like it did then.
     
  12. mojo

    mojo Senior Member

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    Ive seen Alleys video so I didnt watch it again.
    I assume its where he says we cant explain any other reason for temps to rise" SO IT MUST BE CO2"
    Which is the STUPIDEST statement that Ive ever heard.From either a scientist or a clown.
    If you cant explain another reason then you simply dont know.
    Any competent scientist would say we cant explain any other reason for temps to rise so we are uncertain.

     
  13. mojo

    mojo Senior Member

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    I call a BS alarm here .
    There is as much and probably much more money which is pro AGW.
    Goldman Sachs Morgan Stanley are bigger than the oil industry.
    Add to that the Billions from environmental NGOs.
    Then add to that the alternative energy interests.Nukes nat gas pipelines.
    I hope Tom Steyer is not a reincarnation of Ken Lay.
     
  14. tochatihu

    tochatihu Senior Member

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    Mojo if you are saying that renewable energy can be profitable I certainly agree.

    I'm sure we could know the profitability of Goldman Sachs and Morgan Stanley, both publicly traded. How much is derived from carbon trading or the like? I am inclined to think it is a small slice of the pie. Both companies do many things.

    But the whole bundle larger than the global fossil energy industry profit? Where is that BS button, I feel the need to push it.
     
  15. tochatihu

    tochatihu Senior Member

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    Once again mojo points me in the direction of learning

    Global 500 - Fortune

    Of 500 top companies Goldman and Morgan placed 278 and 306. A lot of oil companies did better than that.

    "Goldman Sachs Morgan Stanley are bigger than the oil industry" Sure glad I never said that.
     
  16. mojo

    mojo Senior Member

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    60 minutes refers to Morgan Stanley as the "worlds largest oil company".

     
  17. tochatihu

    tochatihu Senior Member

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    So, Morgan Stanley is profiting from oil, not killing it? Is that your point?
     
  18. Former Member 68813

    Former Member 68813 Senior Member

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    well, it could feel like eternity for humans, yet still be a short spike geologically speaking.

    well if you actually read it, you will learn that layman's "ice age" is not the same thing as geologic ice age that we have been in for the last 3,000,000 years or so.

    as you may remember from another thread, stratospheric humidity is decreasing despite increase in CO2, so not everything is according to the dogma. besides, we didn't discuss how methane can influence water vapor, so don't act like you know everything.

    i don't agree with everything you say, but 100% agree here. all that was shown in the lecture was the association and not causation. if this is the best climatology "experts" can do to convince the skeptics, it's bad, bad science. i actually don't deny the importance of CO2 as GHG (within its limits) or anthropogenic source of CO2 lately, but the video is a travesty of the scientific method.
     
  19. bwilson4web

    bwilson4web BMW i3 and Model 3

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    It was easy enough to find where this came from:
    It seems this claim comes from a 2010 paper:

    Contributions of Stratospheric Water Vapor to Decadal Changes in the Rate of Global Warming

    Susan Solomon,1 Karen Rosenlof,1 Robert Portmann,1 John Daniel,1 Sean Davis,1,2 Todd Sanford,1,2 Gian-Kasper Plattner3

    1NOAA Earth System Research Laboratory, Chemical Sciences Division, Boulder, CO, USA. 2Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA. 3Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland.​

    A cursory glance reveals several assertions of this paper have already fallen from parallel and subsequent research. Berkeley Earth pretty well destroyed the claims temperatures have leveled off found in the paper. But curiously, one of the paper data sources, the EOS MLS satellite, continues to operate today. This means we can see if there has been a significant change in the years after this paper. For example:

    Water vapor is the dominant greenhouse gas in the troposphere. Its greatest influences on climate forcing is in the upper troposphere, and it is generally believed that water vapor amplifies the radiative forcing associated with the anthropogenic increases in carbon dioxide. In the tropics upper tropospheric water vapor is closely linked to sea surface temperature and thus ocean-atmosphere coupling phenomena such as the El Nino southern oscillation can be observed. Energy is released when water vapor condenses and large values of relative humidity, which is derived from water vapor and temperature, show where cloud formation is likely. Stratospheric water vapor influences stratospheric ozone chemistry both by providing a source of odd-hydrogen that destroys ozone and by influencing the formation of polar stratospheric clouds that trigger processes leading to large ozone loss in polar winter. Water vapor has been increasing in the stratosphere, believed due to changes near the tropical troposphere where water vapor enters the stratosphere.

    Source: The EOS MLS H2O Product

    Then there is this 2013 paper: Stratospheric water vapor feedback

    We show here that stratospheric water vapor variations play an important role in the evolution of our climate. This comes from analysis of observations showing that stratospheric water vapor increases with tropospheric temperature, implying the existence of a stratospheric water vapor feedback. We estimate the strength of this feedback in a chemistry–climate model to be +0.3 W/(m2⋅K), which would be a significant contributor to the overall climate sensitivity. One-third of this feedback comes from increases in water vapor entering the stratosphere through the tropical tropopause layer, with the rest coming from increases in water vapor entering through the extratropical tropopause.

    The good thing is the satellite data continues to accumulate and we can extract it for our own analysis. Reading the papers allows us to understand regional and seasonal effects.

    Bob Wilson
     
  20. austingreen

    austingreen Senior Member

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    Well as I said in this thread. I give up. I know I can't get people to understand that calling people denyers is not going to convince them, but I don't think you can find a concerted effort to call people denyers in the 1850s.

    As far as believing in ice ages and the old earth, versus not accepting ghg based climate change, you will find more people don't understand, or have belief's opposed to the ice ages. I'll give you some simple recent poles although this goes off in a tangent. No Big oil didn't get people to be scientifically illiterate, they just are and some religious leaders like the scientific illiteracy.

    4 in 10 Americans Believe God Created Earth 10,000 Years Ago
    4 in 10 believe the earth is too young for multiple ice ages, that man has been around less than 10,000 years, etc. I don't think that has much to do with money interests, but is a big example of scientific illiteracy.

    A really detailed poll
    http://www.rff.org/Documents/Stanford-RFF-Global-Warming-Poll-June-2014-TOPLINE.pdf
    As opposed in ice ages and evolution, americans seem to have a much better understanding of climate science. The missing numbers are the I don't know

    73% thought the earth was warming versus 20%
    78% though thought human activities were equal or greater than natural reasons for the warming. That is a huge number, and what the scientific consensus is about. Only 20% thought it was mostly natural causes.

    I believe that last question is where people get all hung up. 45% thought natural and human causes were about equal, but that is included in the scientific consensus. These folks are not the denyers that some want to make them out to be.

    52% thought government should do a lot or a great deal
    35% thought government should do a little or a moderate amount
    11% didn't want government involved

    Tom Steyer spends big to shift climate change’s political winds - SFGate
    Why did every body that steyer targeted to lose, win, despite polls saying people do understand at least the consensus on climate change? First because his single issue blocking keystone does not really do anything about climate change. He didn't target lowering oil use, or lowering coal use. Jodi Ernst I think was funny, she drives a prius, she said she is doing her part. Lots of the anti-keystone people fly around in private planes. The over $80M went to fight to move oil sands on rail and road instead of through pipelines. He really was fighting to run people out of office that did not want to follow his empty and symbolic gesture, and pretend that would be what it would take to fight climate change..