There are a bunch bunch of ideas for how to build a "thermostat." Some of them might be affordable for even a mid sized economy. We could find ourselves in a world where 26 different countries have competing climate control agendas and toolkits. Presumably Vanuatu has a different take that Latvia.
Perhaps this will be the 22nd century's alternative to resource wars.
Running experiments on the planet we live on is usually frowned upon.
We are in a big fucking experiment right now: what happens if we release fucktons of CO2 into the atmosphere? Most of the developed world doesn't give a fuck.
Regular people can't draw their own conclusions based on self study and own research. Scientifically literate is not enough when you rely on someone else's data and conclusions. So the only way is to present some evidence (plausible stuff) and the conclusion in a loud enough and convincing fashion. What you end up with is a great number of people who are genuinely convinced that global warming is a farce. They have scientists on their side so who are they to argue?
[0] https://arstechnica.com/science/2018/09/scientist-who-thinks...
Most of the world signed the Paris Agreement. The majority of the developed world thinks man-made climate change is real and is a threat. Conflicting priorities and systems of government that are set up for short term decisions make progress much slower than it should be, but saying that we don't care is very unfair to most of the developed world.
You don't like to test in PROD?
I feel that way myself, but I fear we aren't going to end up with any better choices.
Without another Earth to act as a control group, you could say experimenting is technically impossible.
You could but that hasn’t stopped anyone so far
Oh, wait. Some guy did just that in 2012 [1]. Some people claim it was an absolute success, while some others claim that more studies are needed (but they are not willing to fund them!), or we should not play with the only planet we have, etc, etc.
[1] https://planetsave.com/2014/07/02/ocean-fertilization-danger...