@mike_bowler I'm just wondering, are the measured effects actually due to CO2 itself, or is it the reduced amount of oxygen? Does increasing the fraction of nitrogen to similar levels produce similar effects? (perhaps modified for the different molecular weights?)
@phoikoi @mike_bowler Hm, I'm no expert by any means but I'll take a shot at arguing about this anyways lol
So every CO₂ takes up one O₂ and, according to Wikipedia, dry air contains 20.95% O₂ and 0.04% CO₂. So at 1000ppm carbon dioxide concentration we've converted 0.06% O₂, resulting in an atmosphere of 20.89% O₂ and 0.1% CO₂.
I believe that for breathing processes partial pressures are relevant and, if I remember physics correctly, the amount of dissolved gas is directly proportional to the partial pressure of that gas in the air. Meaning we've increased the amount of dissolved CO₂ in our blood by 150% while we decreased the amount of O₂ by 0.29% (*)
So I guess it really is about the carbon dioxide as long as I'm not missing anything?
(*) 1 - 20.89 / 20.95 = 0.29%
@gnarf I'm no expert either, but thank you for posting this and saving me from making the same argument.
“…if I remember physics correctly, the amount of dissolved gas is directly proportional to the partial pressure of that gas…”
Yes. You're thinking of Henry's law: https://en.wikipedia.org/wiki/Henry%27s_law