Your comment is puzzling. It is true that there is nothing we can realistically do about the CO2 that is already in the atmosphere. Whoever lives on this planet will have to deal with it for thousands of years. But we can do something about the CO2 that has not yet been released. The question is not to go back to pre-industrial levels, but to prevent Earth to become an unlivable hell within the next 80 years.
Not quite right. Please read the paper I linked. We can't stop CO2 accumulation by doing things like switching to electric cars everywhere and switching the entire planet to renewable energy sources.
This is a shitty conclusion but I have yet to find anyone who, after having had an honest look at the data can explain how the conclusion is wrong.
BTW, even if we go back to pre-industrial levels it will take tens of thousands of years for levels to come down.
That's the point. If it takes 100,000 years to come down by 100 ppm without humanity on earth how can it possibly take less than that with 8 billion people on the planet?
Even worse, how can the reduction in CO2 happen a thousand times faster?
How can it happen that much faster without expending so much energy and utilizing so many resources that we are far more likely to kill everything on the planet than to "save it"?
EDIT:
With regards to what you say about not adding any more CO2 to the atmosphere. That's also a nonstarter. I understand how it might be easy to think in those terms by creating a simple mental model of reality. However, anyone who understands the industrial economy that makes it possible for nearly eight billion people to live on this planet understands that we cannot eliminate CO2 production to the extent necessary to have an impact.
Put simply, if we erased the United States from the planet on Monday, the output of countries like China and India would continue to grow CO2 at alarming rates.
Erase them from the planet. CO2 would continue to grow.
Erase all of humanity and in 100,000 years CO2 levels will have dropped by approximately 100 ppm.
