"Scientists have calculated that nature cycles about 330 billion tonnes of carbon every year.

Human activities put about 7.5 billion tonnes into the atmosphere - a tiny sum in comparison but enough, say researchers"
...
"If you take out the fossil fuels - for which we understand the CO2 source to within 10% - and look at the rest of the carbon dioxide that's introduced into the atmosphere by our activities, it's uncertain by 100%. "
From second link:
http://news.bbc.co.uk/2/hi/science/nature/7769619.stm

This should understood in the context that politicians want to spend trillions of dollars, drive world economy into deep depression, possibly cause major wars, in order to reduce CO2 literally by immeasurable amounts. Not just immeasurable because they are tiny in comparison, but if 100 times more then their wildest dreams it still would immeasurable.
And why do politicians want to do such a foolish thing, because they want people to think that they are "saving the world".

Save us from the politicians!
They are the ruin of this world.