The problem: If it's a good thing... whatever. If it's a bad thing... Mass Death. Seriously, that's not an exaggeration. Any slight imbalance and we're talking catastrophe. Unless you don't think natural disasters matter much.
We're not saving the environment we're saving our goddamn selves. The environment isn't even a thing. But humans are, and we need a stable environment to get on with our lives.
In order to take the "Mass Death" scenario seriously I want to see some credible indication that our environment actually is that fragile. What I do know (and again, I'm not a specialist) is that most catastrophes that actually happened in the distant past would be expensive for our civilization, but not "catastrophic". Worst case scenario would be something like making a 20 degree belt around the equator a desert, while at the same time making Norther Europe/Asia/America greener (or the other way around). Bad? Depends who you ask. Definitely catastrophic for the equator countries, but not for the humanity as a whole.