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CO2 question

  1. Oct 22, 2009 #1

    As many probably know, there is about to be a climate meeting in Denmark within 2 months, where they will discuss the climate. And some people wants the world to spent alot of money reducing the CO2 from humans, which is a lot of money !

    But has it been proved that CO2 is that bad for the climate ?
    I mean, the danish physicist Henrik Svenskmark has been researching the behavior of the sun, and our placement in the galaxy, to be the reason why the climate changes on Earth. He has come close to actually "proving" it, but he still needs some experiments before he can be sure. And those are going on at CERN as far as I know of.

    So if he is right, that would mean that CO2 plays such a small role in the climate change, that whatever we do to reduce it, it doesn't make any difference.

    This is of course still a theory from Svensmark.

    But as he is trying to prove that it's the sun who are making climate changes on earth, are there any evidence that CO2 has a big effect on the climate, or is it just speculations from politicians and their socalled experts ?

  2. jcsd
  3. Oct 22, 2009 #2
    What is a "Denmark" ?
  4. Oct 22, 2009 #3


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    Place were The Olsen Gang was active back in sixities and seventies.
  5. Oct 22, 2009 #4
    You could also google "Bjørn Lomborg"
  6. Oct 22, 2009 #5
    What is "The Olsen Gang"?

    No one will ever be able to actually prove human generated CO2 is causing climate change, there will always only be strong evidence to support it.
  7. Oct 22, 2009 #6


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  8. Oct 22, 2009 #7
    I laughed when I saw you write "Olsen Gang". Had no idea it was called that in english :)

    But back to topic. So when numerous politicians, "experts" etc. says that we have to reduce the CO2 level generated by us, humans, or else the world will end, they really don't know if it is true or not ?
    It just sounds ridiculous that the world is about to spent so many billions every year - if they really don't know if it is true or not ?
  9. Oct 22, 2009 #8
    it's all a ruse. CO2 we generate is not going to come down. it will only get moved around. the less demand from us, the less price pressure and the better china and developing nations can afford to buy it.
  10. Oct 22, 2009 #9


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    If you want to know whether the temperature-CO2 correlation is strong or not, check science journals or even pop-sci science magazines. They do a much better job than newspapers in giving an accurate idea of what is legitimate science and what isn't.
  11. Oct 23, 2009 #10
    Hey don't knock the CO2 thing, I get good government subsidies because my car puts out less CO2 than others :)

    On a serious note, I think that I heard a guy on the radio saying that even if the CO2 isn't harmful, the research and design that is going into reducing emmisions (because people think CO2 is harmful) from all power sources (including emmisions of other dangerous gasses) is job creating and ultimately, probably, positive.

    On another note, I seem to recall that we are heading into the next ice age, as some may claim, in which case, the greenhouse effect will be just what we need.
  12. Oct 23, 2009 #11
    How positive is the massive destruction of rainforests and the increase of some food prices, which contributed to food riots, while trying to limit CO2 emission?

    But how about it, if increase of CO2 does not lead to catastrophic climate changes?
  13. Oct 23, 2009 #12
    That is assuming that using biofuels is the only action being taken to reduce CO2 emmisions.

    My car, for example uses the same fuel as everybody else's (diesel (not bio diesel)) but with reduced CO2 emmisions, due to weight reduction, engine improvements, aerodynamic improvements and nothing to do with changing the fuel.
  14. Oct 23, 2009 #13


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    There is a hierarchy of problems here, and for sure it is a very exciting topic, one where science, sociology, ethics, economics and politics mix as has never to my knowledge before. As such it is a very fun intellectual endeavour because of the scope of the fields to which it has a relationship.

    As usual with such a complex given, simplicity is usually misguided.

    So let us cut up the multitude of problems in smaller chunks.

    First, the easy, scientific questions:

    - Does increasing CO2 levels, all else equal, have the potential to give rise to a noticeable warming ?

    - Does human CO2 exhaust contribute significantly to any potential increase in the atmosphere ?

    I think there is not much doubt that the answer to these questions is a definite YES. Those that want to contradict this, will have a hard time refuting a mountain of evidence, both theoretical and observational.

    And now the more difficult questions, but still in the scientific realm:

    - HOW MUCH warming, and WHEN ?
    - What about OTHER variations of climate ?

    - what will be the REAL consequences, what will be the real altered climate ?

    And now we leave the purely scientific:
    - What will be the consequences for humanity, for their economy, for the geopolitical shifts in power ?
    - What will be the more indirect ecological consequences ?
    - For whom will this be negative, for whom will it be positive ?

    And now on the economic side:
    - how much will it cost (or make us gain - who knows), and how much will mitigation (and what, and how much) cost ?

    And the political side:
    - how much mitigation - if desirable - is politically achievable ?
    - how much political gain can one obtain by taking a stance (for or against) it, how can one influence public opinion on the issue and how can this promote or be negative for certain politicians/political parties/... ?

    And finally on the ethical side:
    - Do we care ? Should we care ? Do we have any duties "for future generations" ?

    So from the purely scientific observation that "yes, our CO2 emissions do have the potential to influence climate" to "OMG, we have to take urgently some drastic measures" there are a lot of steps.
  15. Oct 23, 2009 #14
    Well, of course CO2 has something to do when it comes to the climate. But as you said, do anybody really know how much of a climate change it is causing ?
    I actually had Svensmark lecture on my University about his theory, and it really was interesting. The fact that hundred of thousands years ago the CO2 level in the atmosphere was about 600 times larger than it is today, and the fact that the climate changes depending on where we are in the galaxy - which leads to more or less radiation from the sun and from other stars, that was just amazing to see...
    I know you have to be critical, but still, it was pretty good. And why not wait those 5-10 years to figure out a bit more about this climate thing, before you run out and use several billion dollars worldwide, that instead, could have been used for alot more.
  16. Oct 23, 2009 #15
    The problem is, that when they use money to reduce CO2 emission, they don't spent those money on researching the field of alternative energy fx. as much as you would, if you used the money just for research. I think I've heard someone say that for every 100 billion, 3-4 billion will be used for research - which in my mind, is not alot compared to the 100 billion.
    People just not to take a big breath and really think this through, instead of hurrying into possible failure.
  17. Oct 23, 2009 #16
    2nd gen biofuels use waste plant matter, and don't cause the food shortage problems that 1st gen biofuels do.

    But also redargon is right, there is much much more we can do to reduce CO2 than biofuels. eg, he had a lighter car,

    I realise you don't belive that human based CO2 is causing the problem and thats fair enough you made good arguments for your case in a similar thread a while ago, as there is no conclusive proof for it.

    But it seems slightly foolish to base decisions about things that frankly we just don't know either way on a best case scenario.

    Yes Co2 emissions could be found to be harmless in the future, so doing nothing would be fine, if we do nothing and there is a problem were screwed. There is really no downside to attempting CO2 reduction, apart from the risk that it could be a waste of time.

    Even if it turns out to be a waste of time from a global warming point of view, anything that humans can do to reduce theri impact on the environmant is a good thing.

    Now the land clearing for rape seed/1st gen biofuels simply traded 1 problem for an arguably worse one, and was incredibly short sighted as food >> fuel. But reasearch in that area, has allowed 2nd gen biofuels to be created which solves the problems of 1st gen.
  18. Oct 23, 2009 #17


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    Nobody knows anything for sure. What you can say is "to the best of our knowledge" (which can be totally wrong of course). And here, you have all kinds of conspiracy theories, but that doesn't exclude "scientists with an agenda" (be it "getting funding" or "getting attention"), and so it is not easy to find out what's really "to the best of our knowledge" (which adds the sociological dimension to this problem).

    But do not make the mistake that was also made back "it wasn't known for sure that smoking causes cancer".

    The problem as I see it, is that there are several effects at work, which are rather complex, and which are difficult to model accurately, or to even measure accurately, and we are, after all, looking at a very small effect: is it 1 degree, 2 degrees, 3 degrees, 4 degrees...
    on a system where there is already about 30 degrees of greenhouse effect, and where there are rather powerful and complex feedbacks cancelling each other partly.

    So it is a matter of achieving high accuracy on a difficult and complex problem.


    It won't be 5 - 10 years, to know for sure, it will be 30 - 50 years, to know for sure. It's very easy: by the time the signal is strong enough to be "clear", it is too late. What we want to AVOID is a strong and clear signal. So obviously, it's going to be difficult.

    It's a bit like on the stock market: you are suggesting that we buy or we sell when we clearly see what the stock is doing. But by the time you clearly see it, it is too late to buy or sell !
  19. Oct 23, 2009 #18
    But why is it so difficult to measure ?
    Isn't it just putting some CO2 into a 2-splitted closed box, put some CO2 in the middle, heat the bottom and see how much gets through and how much is thrown back ?
    Or is it when you enlarge the scenario it gets complicated ?
  20. Oct 23, 2009 #19


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    That was already measured and/or calculated many times. Trick is, story doesn't end here.

    When temperatures goes up, vapor pressure goes up, thus there is more humidity and it will change amount of clouds, which will in turn change albedo and greenhouse effect at the same time.

    Changes in humidity and temperature change vegetation, whcih in turn changes color of the ground, changing ground albedo, changing ratio amount of energy reflected/absorbed. But changes to vegetation also mean sequestration of CO2 changes, not to mention fact that speed of decomposition of organic matter changes, which means we have no bloody idea about whether amount of CO2 will go up or down as a net effect.

    At the same time CO2 dissolves in water, potentially lowering its pH. What effect does it have on the amount of vegetation in seas - vegetation that will either decrease, or increase amount of CO2? And how much CO2 and how fast can be absorbed by seas/oceans?

    Add to that factors that we have no idea about - how will the air/sea circulation change, again changing amount of clouds and albedo - and you have just scratched the surface.

    And note that I can list these effects just using my imagination, not even pretending to know anything about weather and climate.

    All I know about weather is that there is 6 deg C now outside and it is quite normal this time of the year in Warsaw :wink:
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