Greenhouse gases make up approximately 1.5% of the atmosphere. CO2 makes up 3.6% of this 1.5% with 95% of this 1.5% being water vapor.
Humans produce around 3.5% of the CO2 released each year.
Australia produces in total 1.3% of human emissions
If Australia reduces our CO2 by 50% we affect 1.3% x 50%x 3.5% of the worlds CO2 released in one year or 0.023% - or 0.023% x 3.6% of approximate contribution to greenhouse gases = 0.000828 %.
This is well beyond any confidence or tolerance of measurement. this doesnt even consider the other effects on the climate - such as the biggest one - the sun!
