Runaway Global Warming

Discussion in 'Earth Science' started by Facial, Jul 11, 2014.

  1. Quantum Quack Life's a tease... Valued Senior Member

    Isn't Billy T speculating on only a partial Albedo?

    That is to say, that the clouds may appear darker from above and not necessarily black as in asphalt. ( you may have suggested?)
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  3. billvon Valued Senior Member

    He can answer that. I assume he is assuming the ordinary definition of albedo, since he posted a table that uses ordinary albedo.
    If they appear white they have a high albedo, and reflect most energy. (Most of the energy from the Sun is within the visible spectrum.) And of course we see via reflected light; we see things that reflect a lot of light as white, and things that reflect almost none as black.
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  5. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

    On (1) No the burning of all the wood in Dersden's buildings would be a tiny release of heat compared to the coal burnt in Germany during the same four days Desden smoldered. Also Dersden's smoke was not transport to high altitude by the Hadley cell circulation. I don't think it went even half as high as a thunder storm cloud does. They rise to much higher heights as a "Taylor instability" - water vapor in the rising column of air condenses and keeps it much warmer and less dense (buoyant) than the air it is rising thru. When this is no longer the case at the top, but still is lower down, the cloud spreads out laterally as more is still feeding up.

    On (2) Again no. I didn't say that the soot would turn the clouds black; but a very small fractional content of soot would (due to the hundreds of small angle scatterings / random walk in "angle space" nature of cloud reflections). I said the albedo could be reduced from ~2/3 to ~1/3. Look at the chart in post 517 of the albedo of various substance: 1/3 is typical of ice and old snow - they don't look black from above, do they?

    Here is link I made almost a decade ago on the Dresden air raid (its mathematical planning of the bomb mix mainly but an interesting story about the planners strike going all the way up to Churchill to resolve.):
    Last edited by a moderator: Dec 4, 2014
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  7. billvon Valued Senior Member

    You said albedo would be effectively zero. That would be black. You cannot have an almost zero albedo and still have it look white.
    And that paled in comparison to all the coal burned in England in the 1950's. The black smog killed thousands. But even then there was no significant increase in temperature; indeed, temperatures did not start a rapid rise again until about 1978.
  8. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

    If I said that it should or must have been in the context of heavy (a few % soot fraction) I'm sure I said "reduced to 1/3 from 2/3" and that is how you said that makes a 400W/m^2 increase in solar heating (and I agree it would for the high clouds that were reflecting 2/3).
    Of course not. London is a tiny fraction of the cross section intercepting sunlight compared to the Hadley circulation between -30degrees South to +30 degrees North latitude. That is half the total earth's cross section for sunlight!
  9. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

    Humans are still reforming to uninhabitable the earth:
    Links to four related stories below at the link above:
    1. NOAA: Globe sets 5th hottest-month record of 2014 Associated Press
    2. UN weather agency: 2014 on track for hottest year Associated Press
    3. GLOBAL ECONOMY-Creaking euro zone, China sound warnings for global growth Reuters
    4. Climate change adaptation comes of age in U.N. talks: TRFN Reuters

    No.3 sounds like some good news, but is not - will just relax some of the efforts at alternate energy system* as oil glut continues with ever lower prices - Already US demand for "big cars" is rapidly increasing with < $2 prices for gasoline appearing.

    * Including a switch to sugar cane alcohol fuel. Perhaps somewhere in the universe there is intelligent live, but not here.
    Last edited by a moderator: Dec 6, 2014
  10. zgmc Registered Senior Member

    In another forum that I frequent, someone just posted how they think CO2 is just a fad. Nothing to worry about. We should be more concerned with over-fishing. I wonder what the world would be like if Ted Danson had taken up global warming instead...

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