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- #281
I believe I did explain it... more than once. But since you asked sort of nicely...First of all the phrase artificial isn't correct. Just strike that word because all it shows is your bias. If you want to take care of this world for future generations, 580 ppm is preferable to 300 ppm.
I don't agree with your assessment that we shouldn't use coal or oil. The whole point of this thread is that 580 ppm is superior to 300 ppm. We will get off of coal and oil in due time. When it's right to do so.
Why do you think 580 ppm is superior than 300 ppm? ... you've not really clarified the cause-and-effect of any benefit ... and show your math please ...
The conditions which led to the glacial and interglacial cycles of the past 400,000 years and the transition from a greenhouse world to an icehouse world ~3-5 million years ago, still exist today. Namely, polar regions being isolated from warm marine currents and atmospheric CO2 of ~400 ppm. Given these background conditions and a triggering event whether it be gulf stream switch off or milankovitch orbital cycles or both affects temperatures (‘insolation’) at 65deg N which is a critical location for triggering Northern Hemisphere glaciation. Extensive glaciation can begin at the south pole at ~750ppm but at the north pole the threshold is 280 ppm. The reason for the difference is because the south pole has a continent parked on it whereas the north pole has an ocean parked over it. So it is much easier for glaciation to occur on the south pole than the north pole.
So at 580 ppm we remove one of the key requirements for glaciation to be triggered at the north pole.
The following link is a pretty good read and mentions most of the things I have discussed.

Quaternary glaciation - Wikipedia
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