http://www.nasa.gov/audience/forstudents/9-12/features/912_liftoff_atm.html
The atmosphere is primarily composed of
Nitrogen (N2, 78%),
Oxygen (O2, 21%), and
Argon (Ar, 1%).
(H2O, 0 - 7%),
Ozone (O, 0 - 0.01%),
CARBON DIOXIDE (CO2, 0.01-0.1%)
How many sources (human and non-human) contribute to this 0.01 - 0.1%??
In percentage terms what do humans contribute to this 0.01-0.1%.
Even if humans are 100% responsible to carbon emissions then it's ONLY 0.01-0.1% of the atmosphere.
Australia ONLY contributes 1.2% to this 0.01-0.1%
And these idiot environmentalist are telling us that Australia cutting it's Carbon emissions by 5% will make a difference???

The reality is the environmentalists do not know in percentage terms how much carbon humans contribute to the carbon cycle
Professor Garnaut doesn't know and he's been paid to advise Labor on this issue