Sceptic agrees global warming real.

Discussion in 'Earth Science' started by Trippy, Oct 30, 2011.

  1. Read-Only Valued Senior Member

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  3. Zeno Registered Senior Member

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    This is for the global warming skeptics. June 2013 was the 340th month in a row with the monthly average global temperature was above the 20th century average
    global temperature.
    http://www.climatecentral.org/news/june-extends-globes-warm-streak-to-340-months-16258
    Now then, if there is no warming then the global average temperature is just as likely to be below the average as above the average.
    So to show that there is no warming, take a coin and flip it for heads or tails. If you can flip 340 heads in a row you will have made your case.
    The probability is 1 in 2^340 or about 1 in 2.24 x 10^102. Absolutely no way.
     
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  5. river Valued Senior Member

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    What I interesting is it seems that most people ignor what is happening in the Arctic
     
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  7. sculptor Valued Senior Member

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    "global warming" may not be the dumbest phrase I ever heard, but it sure comes close. It is a highly inaccurate rhetorical soundbite means of expressing anthropogenically assisted atmospheric forcing which is effecting the earths climate.
    Even a cursory glance at paleoclimates that were warmer than today shows that they were (as far as the proxies take us) more equable than today.
    While it was 8 degrees warmer and wetter and forested in the arctic(see the lake e'lgygytgyn studies), the temperate zones saw little change, while the tropics dried out some(at-least in brazil)---that's high latitude and high altitude warming, not quite global, and calling it such is like assuming that all women or all blacks or all whites are alike. It is, on a good day, a pathetic estimation of an average.
    Unless we are in a super interglacial(lake e again) this interglacial ain't got much more time.

    To the best of my knowledge, no one is certain just why it is that we drift into an ice age, or out of one, nor how long this one will last. We ain't even certain how many have preceeded this current one.

    If this ice age ain't over, and we ain't in a superinterglacial, the ice should return within a couple thousand years. Add in another massive volcanic eruption and a volcanic winter, and the ice may come on real damned fast, with attendant famine war and disease.
    on the other hand:
    With with continental ice sheets and lower sea levels, the archaeologists will finally be able to begin to search for early modern human habitations and migrations along the coastlines of 20-40kybp..........................yippee
     
  8. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Yes, that is true and even the atmospheric CO2 levels have been several times higher than they are today with life surviving. Thus, you and many others conclude that while “global warming” may be inconvenient for some and a blessing for others (lower shipping cost with ice free Arctic Ocean, more useful Siberia, etc.) it is no threat to life on Earth.

    What this POV ignores is than the RATE of CO2 release with burning of fossil fuels is hundreds of times faster than ever before in Earth's history. This may convert Earth into a cooler version of Venus with a high pressure steam atmosphere - a completely sterile planet.

    There is a thread called “apocalypse soon” (at http://www.sciforums.com/showthread.php?133084-Apocalypse-Soon) in which I have disputed the OP's idea that “peak oil” will make such damage to the economies of he world that > 95% people will die. I argue that man is adaptive and there are already well known technologies for societies to run on solar energy at quite affordable costs. For example as Brazil* now mostly does and the entire world could as I show in post 1436 of that thread. (many pages back now).

    But what I want to call your attention to is how the earth may switch to its hot stable state as Venus did some millions of years ago. I. e. a state with IR opaque atmosphere, making the surface temperature of Venus above the melting point of lead. Some of Earth's metals would be melt too if Earth were in its “Hot Stable State”

    Methane, CH4, is a GHG at least 10 times more effective at blocking IR radiation from escaping into space than CO2 is. In Earth's past the “global warming” was much slower than now with man's rapid burning of fossil fuels, and thus the release of CH4 stored in methane hydrates was much slower – so slow that the atmospheric destruction of CH4 kept the concentration of CH4 in the air very low. That is not the case now – the CH4 concentration is rising long with that of CO2.

    Recently, in the shallower Arctic Ocean where water is warming rapidly, methane hydrates are decomposing, releasing CH4. I.e. kilometer diameter “clouds” of bubbles of CH4 are rising up to the surface and then entering the atmosphere. Fortunately CH4 is destroyed by atmospheric processes with a half life of only slightly more than a decade. Unfortunately, there is more carbon stored in the methane hydrates than ever was stored in all the coal and oil!

    There exists the real possibility that we have already activated two positive feed back loops that may make Earth sterile in a few thousand years. I. e. the unprecedented rate of CO2 now making an unprecedented rate of CH4 release from methane hydrates is self accelerating process. If the “loop gain” of these feedback loops is already greater than unity, EARTH WILL SWITCH TO ITS HOT STABLE STATE. If the loop gain is not yet greater than unity it may be possible thru reduction of the RATE of CO2 release to prevent a thermal run away of Earth's surface temperature.

    I posted some of these concerns in the above thread as a completely sterile Earth with a high pressure steam atmosphere would be a real catastrophe and “peak oil” is only an inconvenience, requiring more utilization of solar energy. See first post1056, and then 1061 of the above link.

    * Less than 5% of Brazil's electrical energy comes from fossil fuels. ~85% is hydro-power, more than 5% is thermal steam made by burning the sugar cane after it has been crushed and supplied the distillation of alcohol heat requirements, wind and solar PV make a few percent each and Brazil's one nuclear site makes about 1%. The sugar cane alcohol not only fuels Brazilian cars but also now Braskem is making 400,000 TONNES of plastic annually from sugar cane, not oil, at lower cost than oil at $90/ brl or greater.
     
  9. sculptor Valued Senior Member

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  10. Rav Valued Senior Member

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    I keep meaning to drop in here just to ask:

    Because this skeptic has finally gotten around to agreeing, does that mean that global warming really is real now?

    Done

    Please Register or Log in to view the hidden image!

    Have fun!
     
  11. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Yes that too is true. After a large volcanic eruption the ice cores do record much higher rates of CO2 release than now. It can takes even a few decades for that "burp" of CO2 to be removed, by growing plants and absorption into the oceans. What I am concerned about is the STEADY and slightly accelerating CO2 release acting for 100 or more years.

    It is a simple fact that submarines in WWII era could use their sonars everywhere in the shallow Arctic waters but now can not see thru the rising clouds of CH4 bubbles. The atmospheric concentration of CH4 is now rising and was basically static with release rate = destruction rate until about 25 years ago. At what level will Earth be beyond the rescue with rising CO2 & CH4 concentration? I. e. trapped in a greater than unity positive feed back loop with run-a-way surface temperature, until the great heat capacity of the oceans with surface boiling stabilizes the surface temperature at ~105 C for more than a million years?

    Can you (or anyone) tell at what level and rate of release of CO2 & CH4 atmospheric concentrations the loop gain exceeds unity?
     
    Last edited by a moderator: Aug 13, 2013
  12. billvon Valued Senior Member

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    We have seen far faster rises in CO2 concentrations. We have seen far higher total CO2 concentrations. No "steam death."

    We have seen far higher CH4 concentrations.

    Yes, that could happen. You could spontaneously burst into flames as well - and that event is even more likely. Still, no need to buy asbestos underwear.
    Some safe bets:

    CH4: when it exceeds 500 parts per million, since historically there have been such concentrations without "steam death." (Currently at 700 parts per BILLION.) So you'd have to increase it almost 1000x.
    CO2: when it exceeds 3000 parts per million, since historically there have been such concentrations without "steam death." (Currently at 400 parts per million.) So you'd have to increase it about 8x.
     
  13. Trippy ALEA IACTA EST Staff Member

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    Assuming Earth even has sufficient insolation to achieve such a state. I have previously posted a paper for Billy T, which it seems Billy T has disregarded thatsuggests that insolation would have to increase by at least 10% for Billy T's hypothesis to be plausable.

    It seems Billy T has chosen to disregard that paper and pursue his hypothesis instead.
     
  14. billvon Valued Senior Member

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    Agreed. It would have been more accurate to say that such a state will not occur when CH4 is below 500 parts per million and CO2 is below 3000 parts per million. Above that it is still unlikely.
     
  15. iceaura Valued Senior Member

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    24,099
    Playing devil's advocate here (my hunch is that if the clathrate gun were set to that delicate a trigger it would have fired already, or more likely never have loaded itself), we note that in the past times of high methane and CO2 concentration both the sun was considerably dimmer, and putting out somewhat different wavelengths.

    Also, the heat distribution and cloud cover patterns were quite a bit different.

    That is, the assumption that if we have survived high methane and CO2 concentrations before without boiling out we surely will again, is not quite safe.
     
  16. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    No, I did not “disregard” paper you linked to with this post: 1162 of the Apocalypse soon thread:
    I did NOT “disregard” the paper. I carefully read it and then I pointed out that the paper made two very questionable assumptions that FORCED their conclusion.

    The first assumption is totally false - impossible. It assumes a thick band (40% of the atmosphere they consider) next to the surface is at a fixed temperature of 200K. (100K LESS than the current surface temperature!) They even admit that without this assumption, their solution “blows up” - temperature increases without limit! Their second assumption also is nearly impossible. With either of these false assumptions, yes their model shows there is no run-a-way temperature problem.

    Here is my earlier posted comments on their paper:
    In post1171 you did try to defend these improbable or false assumptions that force the conclusion they reached.

    I was not persuaded of their merit but did not reply to your post 1171. I will let the reader review post 1171 and seen if these indefensible assumptions that force the conclusion are reasonable. I think your arguments about Venus are irrelevant as I am not suggesting the same mechanism that caused Venus to switch to it hot stable state is operating on earth. Man's unprecedented rapid release of CO2 from fossil fuels, not plate tectonics or lack there of is the potential threat to life on Earth.

    Again let me stress, I am not predicting that Earth will switch to its hot stable state with a high pressue steam atmosphere – only expressing concern that it could via very well accepted physical mechanisms if man releases CO2 at and every increasing rate as he is now doing. At what level and rate of CO2 release the positive feed back loops the CO2, CH4 & H2O green house gas concentrations must reach for greater than unity gain and thus a run-a-way thermal instability is unknown but such a level and rate combinations certainly does exist.
     
  17. Michael 歌舞伎 Valued Senior Member

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    Burning CH4 releases a lot less CO2 compared with burning oil.

    Also, the world population is proposed to peak and begin a gradual decline beginning in 35 years, if so, the stress on the planets eco systems combined with technology may lead to a an ecological resurgence.
     
  18. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    It is certainly "loaded" See reference in 3d quote of my prior post 128 that states there is four times more tons of methane hydrate on just the East Siberian continental shelf than all the 350 million tons of green house gases man has released. It also stats the there are 1000 tones in the frozen Siberian tundra and it is being released now at an ever increasing rate.That same link note the methane hydrates are now decomposing, not only in the rapidly warming arctic waters but also from the Chatham Rise seafloor off New Zealand. Currently only the relative shallow ocean bed methane hydrates are decomposing as greater pressure tends to stabilize them. SUMMARY: The clathrate gun is not only "loaded", its fuse is burning.

    It may have fired weakly at least twice before. Many believe it was responsible for the two larges mass extinction of life on Earth but those earlier "explosions" of CH4 release were mild compare to the one that appears to be coming. Back then the rates of initiating CO2 release were much lower than now - man is now burning a century of stored solar energy (oil, coal and natural gas) every day!

    Note this is NOAA article title, not a "click on" link. To read article, google search this title.
     
    Last edited by a moderator: Aug 14, 2013
  19. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Yes replacing BTUs of oil with methane is a help, but that is not what Japan is doing. They are replacing nuclear energy with more fossil fuel burning. I also think they will disturb the safely stored deep methane clathrates with their extraction and release tons of methane unburned.
     
  20. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Where did you get these values? You seem to not be aware that even increasing the current 400ppm of CO2 to 1000ppm, much less 3000ppm would not produce much global warming as CO2 can only block the escape of IR in its absorption bands and is already at current concentrations blocking about 2/3 of that part of the IR "earthshine." CH4, in contrast has wider bands and is far from fully blocking the IR it could.

    CO2 is a linear molecule: OCO and CH4 is a "3D" molecule so has more and wider and more complex rotational and vibrational bands for IR absorption, but neither is polar. H2O is a polar molecule (both the H are on the same side of the O with a 105 degrees angular separation spread. Thus, the H side is permanently positive and the O is permanently negative.) H2O is a much stronger IR absorber than even CH4 which is more than 10 times as effective as CO2, molecule per molecule basis even if CO2 were not already nearly saturated with little possibility of absorbing more. This is a very complex, inter acting set of molecular absorbers making global warming.

    Simple numbers like your give are essentially meaningless. A 10%, just guessing, increase in the water vapor concentration would increase global warmingmuch more than a 1000 fold increase in CO2 concentrations would! Probably the most important increases in global warming are being caused, in a positive feed back way, by slight increases in the average amount of water vapor the warmer air can hold prior to raining some out. As I said it is a very complex problem and I doubt anyone really understands it or even has all the interaction cross section and altitude / UV effects coefficients (especially those related to the chemical destruction of CH4) correct.

    Do you want to bet the existence of life on earth that they do? Or would it be wise to switch away from burning fossil fuels ASAP (like Brazil has basically done. Read how world could at post 1436 of the apocalypse thread.)?
     
  21. Trippy ALEA IACTA EST Staff Member

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    Yes you did. You disregarded it on the grounds that you felt ts assumptions were fatally flawed. The fact that you have disregarded it is self evident in this thread.

    And as I pointed out to you in my reply:
    Your first objection is invalid - they modeled the Earths atmosphere behaving in the same way we observe Venus' atmosphere to behave today.
    Your second objection was based on a faulty interpretation of Diagram 3. Diagram 3 is simply illustrating ONE of the scenarios they modeled. They modled a range of surface pressures up to 270 bar which is more than the current surface pressure of venus and what they expected if earths entire inventory of ocean water was evaporated.

    You never addressed either of these rebuttals.
    You did not explain why Earths stratospher should not be treated isothermally.
    You did not explain why Earths sratosphere should have a temperature higher than that of Venus' stratosphere.
    You did not explain why you expect Earths atmospheric pressure to exceed a value in excess of that observed on venus and based on the complete evaporation of earths inventory of ocean water.

    Perhaps you'd care to address these points now before you peddle your agenda further?

    How magnaminous of you. Letting readers wade through around 700 posts to find the one post you're referring to.

    Luckily for them I quoted my reply in full.


    First off, nothing I have p?resented is Venus based.
    Second off, the modelling presented in the paper was based around, as I recall, the combustion of Earths entire carbon reserve, and the evaporation of the entire oceanic water inventory of the earth, an they still came to the concluion that it required higher insolation than the earth currently receives.
     
  22. billvon Valued Senior Member

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    They are historic maximums of both gases.

    I am quite aware of that, which is one reason I find your "steam death" scenario amusing.

    Correct. And even when its concentration was almost 1000 times higher it did not cause "steam death."

    Question - how much higher do you think we can push CH4 concentrations with our best efforts? 1 part per million? 2? 10? You would really have to come up with some bizarre and extradordinary mechanisms to claim a 10 part per million end concentration (over 10 times what we have now) - and even that is 50 times less than the highest historic concentration.

    And wild guesses such as yours are even more meaningless.

    Really? A cloud covered planet would absorb more total energy? Can you think of any reason that might be an erroneous assumption?
     
  23. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    We must agree to dis agree, but I will respond to this part of your post.

    The authors themselves admit (Bottom of page 475.) and now red text in my post 133: (1) they made that constant 200K temperature thick layer next to Earth surface assumption to make the calculation affordable with the computers they had back when it was done (before 1986) AND
    (2) They note that the prior calculation efforts which did try to work thru the radiative / convective structure of the lower atmosphere blew up - had unlimited temperature increase.

    It is also suggestive of error that no one seems to be quoting them that I can find. Perhaps that is just my lack so searching skills. Do you know of any recent published papers that cite them with approval?
     

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