Fuller doesn't know his Arrhenius
Svante said 5-6C for doubling CO2, including feedbacks:
http://en.wikipedia.org/wiki/Svante_Arrhenius#Greenhouse_effect
Fuller needs to work on his accuracy.
The interesting astronomy connection is that scientists were trying to calculate the Moon's surface temp in the late 1800s by measuring infrared radiation coming from it and had to account for CO2 absorption in the Earth's atmosphere. They realized that measuring IR from the moon near the horizon as opposed to at zenith imitated the effect of increasing CO2 in the atmosphere. This is in the book, The Long Thaw.
Would probably make a good high school science experiment today.