science

That's not what an abstract is.

And just because you failed to understand something doesn't represent an inadequacy on the article's part.

It's quite demonstrable that atmospheric CO2 levels have been increasing over the decades, and that the increase is accelerating rather than slowing down.

Data that concrete can easily be extrapolated. "If we continue polluting at the current rate, the air will be unbreathable in X amount of years" is not a wild claim.

And changes in blood chemistry that are correlated with atmospheric CO2 level increases are a valid means of studying how much pollution humanity can tolerate before it has catastrophic effects.