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An idea to reverse global warming

  1. Oct 13, 2017 #1
    Elon Musk says we can terraform Mars by converting its CO2 and H2O into CH4 and O2 using solar power, the latter two compounds being quite useful. Can't we use his idea to reduce the CO2 in our atmosphere and reverse global warming?
     
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  3. Oct 13, 2017 #2

    Bandersnatch

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    There are various carbon capture methods proposed or in use, but I don't think this one is preferable on Earth, for a number of reasons:

    1. We don't need more oxygen,
    2. The reaction produces methane, which can't be released into the atmosphere - it's an even stronger greenhouse gas than CO2,
    3. Methane can't be used industrially without defeating the purpose - burning it simply reverses the reaction, so it's a net waste of energy for no gain;
    4. Storage is difficult.

    For methods deemed useful on Earth, google 'Carbon capture and storage' (often abbreviated CCS), 'Carbon dioxide scrubbing' or 'Carbon dioxide removal' (CDR). There's some overlap in what these terms mean, but they generally differ by where the capturing occurs.
     
  4. Oct 13, 2017 #3

    anorlunda

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    None of us should use ad hominem attacks in public debates. Invalid debating tactics are part of the cause of this post-truth era.
     
  5. Oct 13, 2017 #4

    sophiecentaur

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    If terraforming Mars is going to be so straightforward then how is it proving to be such a problem on Earth? Mr Musk has had a fairly long line of successes in his business life. He may be overstretching himself in his ideas about Mars. It's a bit like the change from a Big Businessman to President of the USA.
     
  6. Oct 13, 2017 #5

    sophiecentaur

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    I see where you are coming from but I my argument is based on the attitude and interpretation of data. Aren't politicians and big businessmen fair game in this type of discussion?
    In my Elon Musk rebuttal post I am surely justified in calling his views into question. I am not aware that he has fully costed and assessed the terraforming idea.
     
  7. Oct 13, 2017 #6

    ISamson

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    Could you give us the link (or source) where you got Elon Musk's quote from?
    Thanks.
     
  8. Oct 13, 2017 #7
    Certainly, a major component of global warming has resulted from human activity. And certainly a major component of that is CO2 emissions. But water is a far more potent green house gas, and modern agriculture is pouring lots of that into the air. So I am not convinced that global warming is well-modeled.

    More importantly, simply arguing that dumping CO2 into the atmosphere will cause catastrophe is not a sufficient argument for any specific action. What is needed is argument that demonstrates that a proposed specific action will not cause as much damage as it will alleviate. And, in this case, "damage" doesn't mean any change to the geography or environment of the planet, but to the economy of the people on that planet.
     
  9. Oct 13, 2017 #8

    Bandersnatch

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    Water condenses.

    Can we stick to the OP and not infringe on forum rules regarding AGW?
     
  10. Oct 13, 2017 #9

    sophiecentaur

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    I agree that the overall connection between human activity and global warming may be more tenuous than many people think. However, there are two issues here. Many 'Denyers' try to go one step further back and deny the evidence for warming when they would be more justified in discussing possible causes. I often ask myself what my attitude would be if I had my life savings tied up in a high CO2 producing industry. I would like to think that I would still believe the evidence.
     
  11. Oct 13, 2017 #10

    sophiecentaur

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    What does the "A" stand for? Against?
     
  12. Oct 13, 2017 #11

    Bandersnatch

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    Anthropogenic (Global Warming).
     
  13. Oct 13, 2017 #12

    ISamson

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    What does that stand for, may I ask?
     
  14. Oct 13, 2017 #13
    At the 67th (Mexico) and 68th (Australia) International Aeronautical Congress's, Elon described using the Sabatier process to provide fuel for the return trip to Earth. And at the 68th Congress, he referred to the overall project as Terraforming. However, I am not aware of him proposing the Sabatier process as a method of improving the Martian atmosphere.
     
  15. Oct 13, 2017 #14

    sophiecentaur

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    That's a big word for a Friday lunchtime. :smile:
    EDIT: Google told me it was All Going Well. Very confusing for an old chap.
     
  16. Oct 13, 2017 #15

    sophiecentaur

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    So it's actually a long way from terraforming. He may well have been 'over-reported' about that one.
     
  17. Oct 13, 2017 #16
    His remarks at the 68th IAC were a very long way from what most people think of when they hear the word "terraforming". As I recall, he actually used that term, but only in the context of making large Martian cities. When he made the statement, the graphic that was being shown was simply a city that was expanding with the addition of buildings - not by changing the outdoor atmosphere.
    Certainly Musk is selling Mars. He described making Mars "a nice place to live". And the reporting that I read was good - it included a video of his entire presentation. Of course, there's nothing stopping other news outlets for carrying his remarks beyond their meaning -either intentionally or unintentionally.
     
  18. Oct 13, 2017 #17

    russ_watters

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    We'll, at least it is better than burning trees for electricity, which is net neutral over an infinite timeframe, but eliminates storage (see Germany).

    Another issue for Earth vs Mars is that while on Mars the concentration of CO2 is high, on Earth it is low, so you have to use additional energy to separate it...

    ...unless you just target exhaust gases, using solar power to recycle them....but then as you say, the fuel becomes superfluous and the power input is only the solar.
     
  19. Oct 13, 2017 #18

    Bystander

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    Does not pay the cost of pumping it across the room ( @ ΔP = six inches of water, and 400 ppm).
     
  20. Oct 13, 2017 #19

    mfb

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    Heating up is the easier direction both on Mars and on Earth. Heating up Mars makes the conditions better for humans, heating up Earth (it is easy! We do it right now) does not.

    Anyway, Musk proposed that reaction to produce rocket fuel and to use oxygen and methane for enclosed stations on Mars. This is not terraforming.
     
  21. Oct 13, 2017 #20
    It wasn't a quote, just in Musk's mind. Google "musk methane mars" and then Find "methane".

    The most convincing answer to my question was the 400 ppm CO2 on Earth vs nearly 10^6 ppm on Mars.
     
  22. Oct 13, 2017 #21

    sophiecentaur

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    I realise that the situations are different on Earth and Mars. I also realise that the conditions on Earth are a lot nearer what we want. My comments have been about the Terraforming notion. It is constantly quoted as something that's readily achievable. I am just pointing out that (details aside) the way humans have approached the situation of changes to our Earth environment is not an indication that they are likely to do any better on Mars. There are, in fact many solutions to our present situation here but they are just not attractive and would demand too great a change in lifestyle. The change in lifestyle for someone living on Mars would be orders of magnitude different yet it is assumed that 'colonists' would cope fine with the changes and it would only be a matter of time before Mars could be as good if not better than Earth as somewhere to live. That is an enormous assumption, based on hope rather than experience. (More of the go west young man stuff that space travel enthusiasts always come up with.)
    The small scale project of producing rocket fuel on Mars is an entirely different consideration and I can believe that the figures that have been produced could well be right. This thread and its title are not basically about the production rocket fuel, from what I can see.
     
  23. Oct 13, 2017 #22

    Drakkith

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    So the argument in post #2 that methane is a worse greenhouse gas than carbon dioxide doesn't convince you?
     
  24. Oct 13, 2017 #23

    Evo

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    Thread closed, this does not meet our rules for discussion of Climate Science.

    https://www.physicsforums.com/threads/climate-change-global-warming-policy.757267/
     
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