for how long? Is it offset or moderated by other variables?
Do other variables have a much larger effect?
What could/should be done about it, and what effects would those changes have on CO2 levels? Temperatures on earth? Sea levels? How long would it take for any drastic changes on the part of mankind to have a positive impact in re: CO2 levels, and how would that affect temperatures?
Here's an economist who talks about a thought experiment a consortium of economists had done to try and prioritize what could and should be done given our limited resources.
They concluded that the biggest bang for the buck (or mark, or ruble, or euro) was most definitely NOT making changes to drop CO2 levels, which came in last place among the options they considered:
https://www.ted.com/talks/bjorn_lomborg_sets_global_priorities