A reader has some fair questions about the climate-change consensus:

Some first order technical questions regarding global climate change which still lack unique answers:
1) What is the ideal global average temperature?
2) What is the ideal atmospheric CO2 concentration?
3) By what percentage must AGW emissions be reduced to halt the increase of atmospheric CO2 concentrations?
4) Over what time period must those reductions occur?
5) Over what time period must atmospheric CO2 concentrations be reduced to the ideal?
Since the science is “settled” and the “debate” is over, the answers to these questions should be known or knowable.
If you accept the assertions that the “ideal” temperature is lower than the current temperature and that the ideal atmospheric CO2 concentration is lower than the current atmospheric CO2 concentration, then the answer to question 3 above is “intuitively obvious to the casual observer”; and, the answer to question 4 above becomes critical. The answer to question 5 above can safely be deferred until after the first four questions have been uniquely and definitively answered.
There is a sixth question which is non-technical:
6) Who will convince all of the world’s governments to take the required steps on the required timeframe, regardless of the adverse impacts on their economies?
This sixth question may well be unanswerable.