To better visualize the absurdity of the runaway greenhouse idea, I did RRTM runs for the tropical atmosphere – with increasing amounts of CO2. That is represented by the blue line below. The red line shows the same experiment with no water vapor in the atmosphere.
The first thing to note is that without water vapor, the Earth would be very cold, no matter how much CO2 there was in the atmosphere. The CO2 runaway greenhouse idea is beyond ludicrous.
The second thing to note is that in the real atmosphere (with water vapor) the effect of even huge increases in CO2 is minimal.
Now here is the real kicker. In the real atmosphere, a doubling of CO2 to 550ppm has almost no effect in the tropics. Downwelling LW radiation only increases by 0.2% from 397.1 to 397.7 w/m^2.
Well, it does show a logarithmic curve……..
So the science behind this whole to-do is not even sound.
It was not even sound 100+ years ago and was sidelined until someone needed a research grant so they pulled CO2 out of the waste can!
And after it goes away this time, refuted by reality, it will later raise its ugly head again after humanity once again fails to learn from history.
I know it will because humanity depends on CO2 and there will always be people who wish to control what humanity depends upon.
Our H2O is the next item on the list.
Ah but the tropics are a wasteland of blasted barren rock with no life possible, except intrepid climate scientists who venture there cautiously and reluctantly for data collection and vast and expensive conferences.
Steve,
my you have a paper ready for peer review right here, and it is really short too! Amazing that all those scientists did not know about the effect of water vapor, or the diminishing impact of CO2.
Yes, amazing that Hansen doesn’t understand it. Do you have anything to discuss scientifically, or just the usual personality gossip argument?