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Re: "Climate Change: Do Ice Ages Debunk Climate Science?"

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On Fri, 6 Nov 2015 16:35:42 -0800 (PST)
ibshambat@gmail.com wrote:

> By knowing about these natural cycles and studying them, it makes us
> even more confident that the recent warming we have seen over the
> past 150 or so years is caused by humans and our emission of
> greenhouse gasses into the atmosphere.
> 
> Scientists understand the natural processes behind the previous warm
> and cold periods that lead to ice ages. They occur in regular
> patterns called Milankovitch cycles. These cycles occur because the
> Earth's orbit around the sun is not constant.

  Milankovitch effects are not cycles.  They are aperiodic.

  Glacial to interglacial transitions are synchronized to the
  Milankovitch shifts, but some Milankovitch shifts do *not* trigger a
  climate transistion.

  The reason for this can be seen with basic calculus.  If the warming
  is proportional to the log of the CO2 concentration, then the
  marginal warming per unit of CO2 decreases as CO2 goes up.
  This means the climate becomes *more* *stable* as the CO2 level
  increases.  Ice cores show that cold to warm transitions only occur when
  the CO2 level is low, at around 180 parts per million.

  Looking farther back in time with sediment cores we find that five
  million years ago there were no glacial/interglacial climate shifts.
  During that time the CO2 level was declining.  It was because of this
  decline that climate instability began.  

  Turning back to the ice cores, the prehuman climate cycles had a
  period of about 40,000 years.  Over the last few hundred thousand years
  these cycles have gradually become slower.  The most recent one lasted
  110,000 years.  The most probable explanation for this is some new
  source of CO2 slowing down the natural decline.  I suspect that this
  was caused by the gradual spread of the use of fire by early humans
  that began about 2 million years ago.

  Then around eight thousand years ago the natural decline reversed.
  CO2 levels have been slowly rising ever since.  Humans are prolific
  producers of CO2.  The higher CO2 levels that we have caused
  have stabilized the climate and prevent any new ice ages.

  The earth cannot support even 500 million humans long term without
  carbon sequestration.  Even if you accept genocide as a solution, it
  will not solve the problem.  We need a non-carbon based economy *and*
  carbon sequestration.

-- 
I'm Trawley Trash, and you haven't heard the last of me yet.

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Re: "Climate Change: Do Ice Ages Debunk Climate Science?" Trawley Trash <trash@invalid.invalid> - 2015-11-07 06:27 -0800
  GooGLERS noTthaTguY <abu.kuanysh05@gmail.com> - 2015-11-07 17:57 -0800

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