Physics of global warming
1. The Greenhouse Gases (GHGs) in Earth atmosphere ensure that surface temperature is +15*C rather than -15*C
2 CO2 is the second most important GHG (after H2O vapor)
3 Basic calculations show that doubling CO2 will raise equilibrium surface temperatures by 1.2*C
4 Multiple lines of enquiry show that feedback mechanisms will convert a 1.2*C increase into a 3*C increase (+/- 1*C)
5 Projections indicate that any increase over +2*C would be dangerous