I wonder how we stop at 2 or 3? Or ever? When I suggest that people shouldn't fly in planes, I get responses like I've called their children ugly. I live a very energy-conscious life but I believe it mostly just codes to society as "loser". That I can live with; it's essentially the only way I can live with myself knowing the cost that I create to the planet. But exceedingly few will choose to live the way I do.
"Too late" is also a bit of an academic question as well; there are dragons lurking in the Earth systems - tipping points where carbon sinks become carbon sources and other feedback mechanisms waiting to be tipped. It's very easy to imagine that one tipping point cascades into another to create a runaway effect, though I don't believe there is scientific consensus on exactly where these points are, so we can perhaps hope to avoid them. That the oceans are so much hotter now than models predicted is an ominous sign that our understanding of such a complex system is still quite limited.
"Too late" is also a bit of an academic question as well; there are dragons lurking in the Earth systems - tipping points where carbon sinks become carbon sources and other feedback mechanisms waiting to be tipped. It's very easy to imagine that one tipping point cascades into another to create a runaway effect, though I don't believe there is scientific consensus on exactly where these points are, so we can perhaps hope to avoid them. That the oceans are so much hotter now than models predicted is an ominous sign that our understanding of such a complex system is still quite limited.