The evidence of human caused global warming in the last 150 years is undeniable.
For example, we know that there was no Northwest Passage for the last 100 thousand years, until 1997, when the ice melted for the first time in over 100 thousand years.
If that were all there was too it, it would still be no big deal.
But it isn't.
That is because it not only is still warming, but at some point, water vapor, and other gases like cow fart methane, could start global warming to accelerate in an uncontrollable positive feedback loop, that could heat up the whole planet beyond the ability of any life to survive at all on the planet.
And the point is that no one can argue against the fact there is human caused global warming.
That is not arguable.
What we are not sure about and is arguable is if and when this extinction race condition could or will happen?