"Yes it is. The worlds average temp (without GHGS) is -18'C is what they say."
Oh, and look at that. Now you've added a qualifier to your initial statement; how convenient. This is your initial statement on the matter:
"According to the science you support the worlds temp is -18'C at the surface."
No mention of greenhouse gases in your initial statement. You only added it in when you realised you'd made a major error.
"So they introduced a BS variable"
Have a look out your window. Does the Earth look like it has an average temperature of -18 degrees?
No?
Then you need to explain why- if as you say, the greenhouse gas theory is "BS" then how would you account for the Earth's average temperature being at 15 degrees?
"We know the sun goes down at night and evapouration ceases."
Evaporation does not cease when the sun goes down.
