Steven Mosher,
You wrote –
“What’s so good about 350 as compared to, say, 450?
Larger safety factor”
More unsubstantiated Mosherite nonsense!
Safer how? Define the safety. What is unsafe about 450ppm? When it was 450 ppm in the past, what were the dangers?
Are you really as illogical as you make out, or is it just a facade?
You have so far demonstrated a lack of knowledge in relation to English expression, properties of gases, radiative physics, metrology, the role of CO2 in plant biology, the definition of climate, and chaos theory.
It seems logic is not one of your strong points, either.
My judgement may appear harsh, so if you can point out the documented harm that resulted from an atmospheric concentration in the past of 450 ppm, and why this was discernibly different from the harmful effects of 400 ppm and 350 ppm, (also in the past), it would be appreciated.
I suspect you haven’t a clue, let alone a fact, to support your absurd contention. Give it a try. Actually applying a bit of scientific method might well prove beneficial. You might even revise your opinions, who knows?
Cheers.