There are a few problems with the idea that more CO2 in the air will increase the amount of long wave radiation absorbed.

1/- CO2 can only absorb a very narrow band of radiation, & the current level of CO2 is absorbing 97% of what is being radiated from earth.

2/- CO2 displaces water vapour from the atmosphere. As water vapour is a much more efficient greenhouse gas than CO2 it actually reduces green house effect.

3/- The effect of CO2 is logarithmic, thus any increase in CO2 has a very rapidly decreasing effect, proved by the lack of heating despite rapidly increasing CO2 levels.

4/- CO2 increases the effective convection rate in the atmosphere, thus increasing the cooling. The math on this one was too heavy for me, so I have no personal opinion on it.

5/- There is enough long wave radiation coming in from the sun to fill many times over, the absorption capacity of all the CO2 in the atmosphere. Higher interception of this radiation expels it from our atmosphere more quickly than surface absorption, so cooling the planet.

6/- Ice core examination show that the level of CO2 in the atmosphere was 4 times the current level during some periods of the ice ages.

We are already way past any heating effect of CO2, & no matter how much we burn carbon, it will not stop the coming cold from a cooling sun, as indicated by the lack of sun spots.

"With a little bit of luck, just a little bit of luck" there will be snowballs at Christmas 2025 in Melbourne to throw at Steely & his mates.

"As the models show a larger increase that actual measurement it seems
that the models sensitivity parameter is set to a too high a level."

Very very true.

" it (CO2)will have a significant impact in and of itself"

Define significant. someone might think that 3c is significant but we'll only get 1c. Someone else might think 1c is significant but we'll get 3c. 'Significant' is one of those weaselly words used as a substitute for "I've got no idea".

"advanced modelling have been pretty spot "

That is blatant rubbish.

" CO2 which is the issue and it is increasing rapidly."

Or not...http://papundits.files.wordpress.com/2012/10/historical-co2-levels.jpg

"there will be snowballs at Christmas 2025 in Melbourne"

No that can't be right. Don''t you know that "THE SCIENCE" decided that snow was a thing of the past...( http://dailycaller.com/2014/03/04/top-5-failed-snow-free-and-ice-free-predictions/) and as we all know, the science is settled. QED.

Ahhh yes Hasbeen, thanks I had forgotten that
3/- The effect of CO2 is logarithmic,

Of course that changes everything, indeed it explains why the models
difference to reality and some clever chap should be able to calculate
exactly where we are on the saturation curve.
As the earlier parts of the curve will be almost linear it should be
possible to match the real curve against the theoretical curve and
work out whether there is more to come or it is all over red rover !
Trouble is there has been so much fiddling with temperature readings
it might be hard to decide where we are.

Truly doubt fiddling with the temp figures is a real event
Like the fact science is being used, maybe abused?
To prove the science is wrong

The strongest evidence for global warming is the rising sea level. What I have trouble comprehending is how anyone can think they can model the earth and accurately predict how things will be in fifty years time. That is totally crazy. Even crazier is thinking that the solution to a crazy prediction is to destroy the economy presently. Looking at the world it is apparent to me that bad governments are far more devastating, the consequences evident without need for swallowing a fifty year forecast.

The longer this debate goes on, the more I see sense in commentators like Bjorn Lomborg. There are many real problems that need solving. Prosperous countries will be more likely to find solutions to these problems. The thought of destroying our prosperity to solve an imaginary problem does my head in.

Fester, sea level change is contrary to global warming theory.
Some 70% of Pacific Islands are larger and about 5 or 10%, I forget
exactly, are smaller and the rest are unchanged.
The sea level change is about 1mm a year.
Some tidal marks show falling but some think that is because the
continent is sinking or rising in places. All in all not much use.
See Aukland Uni Coastal Institute