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Author Topic: humans and co2  (Read 1063 times)

Offline eternity

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humans and co2
« on: 20/03/2014 06:36:28 »
Hello,

I was recently reading that in the Devonian period, O2 was at between 21.9% - 27. 4% and CO2 levels were at between 0.34 - 0.35%.
Today (so Ive read), O2 is at 21% and CO2 at around 0.04 %. That made CO2 at around 7/8 times higher than it is now.

I have two questions,

1st/ At what level would rising CO2 levels in the atmosphere become poisonous to us?

2nd/ If it were possible for a human to go back say 350  million years to 27% o2 and 0.35% co2, what would happen?  for example, would we benefit more from the oxygen or be poisoned first?

 thank you
« Last Edit: 20/03/2014 07:02:10 by eternity »


 

Offline alancalverd

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Re: humans and co2
« Reply #1 on: 20/03/2014 06:44:10 »
Important to get the numbers right! Present CO2 level is 0.04%, not 0.4%!

Quote
CO2 is an asphyxiant gas and not classified as toxic or harmful.... In concentrations up to 1% (10,000 ppm), it will make some people feel drowsy. Concentrations of 7% to 10% may cause suffocation, even in the presence of sufficient oxygen,

So we might enjoy the extra oxygen, and also watching sea creatures converting the CO2 into chalk. But don't tell the climate scaremongers, who want you to believe that we are all going to die unless we pay more taxes.
 

Offline eternity

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Re: humans and co2
« Reply #2 on: 20/03/2014 07:03:39 »
thanks, i edited that to 0.04%.    :)
« Last Edit: 20/03/2014 11:58:09 by eternity »
 

The Naked Scientists Forum

Re: humans and co2
« Reply #2 on: 20/03/2014 07:03:39 »

 

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