[nate_meurer]

No, I pointed out specific flaws in those papers. You're just pretending that I'm dismissing them out of hand so you don't have to read them yourself.

Once again, the Australian study that's the source of your original assertion was very small (n=4 in each study group) and very short term (only a few hours of study time). And the paper about bicarbonate levels is a great example of data dredging, where coincident trends are implied to be causative with no further support.

I'm not saying the conclusions are wrong. They could both be right. I'm just saying that their methods are too poor to draw any useful conclusions.

> people who can't cope or perform in the high CO2 environment quit or fail

So here you are dismissing evidence out of hand by pretending not to understand it. Even if submariners are selected based on CO2 tolerance (which is silly), it wouldn't matter. The point is that the US Navy has had a large population to study for long periods of time in highly controlled environments. The same men can be examined before, during, and after exposure to very high concentrations of CO2, while other environmental variables are held constant, and the navies of multiple countries have data from many such populations over decades. That's what produces useful data, in contrast to that tiny, short Australian study you seem to be attached to.