Personally I think that the idea that these trends can ever be revered by some sort of world wide agreement to lower consumption is a pipe dream. People want to eat meat and drive cars and fly on airplanes. As long as they're rich enough to do so you'll never stop them. The only solution to this problem is technology. Some combination of green energy sources plus probably very large scale terraforming.
Yes and no. You can change the carbon efficiency of people's consumption quite a bit with appropriate nudging and consumption taxes. You can also have global agreements paying countries not to exploit their "unburnable" fossil fuel resources. Little things like the EU mandate for ending incandescent lightbulbs can definitely add up. You need technology and policy and economics. The market for power plants is never go…
I always want to suggest to these people that they should start smoking, because clearly, the future's so bright there will be a cancer cure soon.
And, not to be too crass, but that admittedly snarky reply is about one body. The geoengineering proposals are about intentionally influencing a hugely complex system we still don't fully understand, and that is undergoing changes with implications we don't fully understand. All the talk about ecological engineering seems to assume that the worst that happens is it doesn't work. That sort of naive optimism would be cute if we weren't literally talking about the planet. And if at least some of it weren't duplicitous.
This isn't the reason I chose not to have kids, but it sure does reaffirm that choice. Perhaps the Drake pessimists are correct, and intelligent life can't get off-planet before offing itself.