Our atmosphere recently passed the 400 PPM CO2 level. It is a grim climate change milestone that must be addressed.
98% of climate scientists, every major scientific body in the world and increasingly the general public agree that human greenhouse gas emissions are changing the climate.
Continuing to push the concentration of CO2 higher and higher is a very risky path to follow.
Increasing energy efficiency and renewable energy supply are good ways to lower levels of greenhouse gas production. More important, though, will be changes that lead to simple lifestyles with dramatically lower ecological footprints.
Civilization may depend on how we choose to live right now. We should not be planning for extinction, which is what doing nothing will result in eventually.