Since the Industrial Revolution, CO2 levels have doubled from 250 to 400 ppm. Global temps have risen less than 1 (0.8) degree C but to get another degree you need a doubling of CO2 from 400 to 800 ppm. So, to get 2-3 degrees you may need 1600 ppm. The claim is that double CO2 equals 4 (3.7) watts per meter square of extra solar absorbtion. But when CO2 absorns energy it radiates it in every direction. A hotter Earth also radiates heat away at 5.5 watts per degree. But there are some possible theoretical feed-foward results with water vapor. Some scientists claim hotter temps mean more clouds which account for 90% global warming.
97% Consensus on Anthrogenic Climate Change
these surveys ask:1. "do you believe the climate has experienced some recent warming" and 2. "do you believe that human-generated CO2 is contributing to climate warming?"
If you ask general questions like this, you are going to get a 97% favorable response. What these "consensus" articles are not asking is 1. "how much human-generated CO2 is contributing to warming" and 2. "is human-generated CO2 and resultant warming cause for alarm?"
Mechanism of Cloud Formation
Climate scientists pushing anthropogenic global warming have conceded that water vapor and not CO2 is the major greenhouse gas. However, these scientists maintain that increasing CO2 would still contribute to runaway global warmimg through a sensitive feed-forward mechanism. "Warmers"often talk about a dangerous tipping point with CO2 and climate. According to "warmers", Higher CO2 would produce more clouds which would trap more heat.
The contribution of cloud cover to warming is also complex because certain clouds reflect solar radiation back into space while other types of clouds trap heat. Also, the mechanisms of cloud formation are complex and only more recently being discovered. In this study linked above, cloud formation was dependent on hydrocarbon aerosols produced by trees interacting with cosmic rays. The conclusion being that this mechanism has nothing directly to do with CO2 and that the Earth might not be as sensitive to CO2 as the "warmers" had been claiming.