CO2 emission reduction is the hardest way. It requires coordinating most of the humans in the world to act in a way that disadvantages them, while anyone who defects gets an advantage.
A solution that can be unilaterally implemented by a small minority is much, much easier. Solving technical problems is much easier than changing human nature, which is in fact impossible.
A solution that can be unilaterally implemented by a small minority is much, much easier. Solving technical problems is much easier than changing human nature, which is in fact impossible.