The exact
net feedback number is claimed by the AGW folks to be the only unsolved link in the chain, the only unknown that keeps us from determining the so - called «climate sensitivity».
If half of past warming, or about.4 C is due to man, that means climate sensitivity is around 1C, exactly the no -
feedback number that climate skeptics have thought it was near for years.
There is no good evidence that
feedback numbers are as high as those plugged into climate models, or even that they are positive.
The no feedback number is the grounding point.