Humans need to use science, real objective science, in any analysis. The truth is that we don't know enough yet to be accurately predictive. We are closer than ever but how close are we really?
What are the goals and do we agree on them? Is it survival of our species, survival of as many species as possible or survival of life on this specific planet even if humans die out?
Our current scientific capabilities enable us to look at the past and present more clearly than the future. What we know:
Climate and weather are not the same thing.
Climate is determined by many things, most prominent among them the Sun, the Earth's atmosphere and the Earth's magnetosphere.
Math has clearly told us, if we're willing to listen, that our planet is the only one in the universe to spawn and maintain intelligent life.
The future:
We can strongly predict that the sun will not last forever in a way that supports life on Earth; indeed it will one day envelope the Earth
We are not sure to a fine enough degree how much CO2 is too much to maintain human life
We are not sure if or when a super volcano, asteroid or other natural event could render all our arguing moot
Our goals:
If our goal isn't the survival of our species and as many others as possible for as long as possible then we might as well live it up here without regard for the already doomed planet. I don't have that point of view and would guess that most don't. Knowing that almost all of our technological advancement in the last century has been derived from capitalistic use of fossil fuels, why do so many want to stifle them? The universe is ours, 100% ours, if we can learn enough, quickly enough.