I will be dead long before this has potential serious consequences for me PLUS I try and do my part to be 'green' PLUS I have no intention of ever fathering children (I am not that selfish)...so I really don't care all that much.
If humanity ends due to it's own selfishness...then it is not worth saving and good riddance.
And if they are not that selfish...then they will fix the problem.
Either way...they will probably get what they deserve...and that is fine with me.
10 years ago I would have put money on the latter.
Now...I don't think I would.