In a nutshell...
As far as the atmosphere is concerned, increased CO2 emissions from man this past century or so amount to absolutelly sod all, and even then CO2 is NOT a pollutant that causes global warming. In fact, global warming CAUSES an increase in CO2, not the other way round!
If anything it's the sun that causes most of our climate changes, and the current global warming we are experiencing is because of changes in the sun behaviour eg sun spots etc.
The CO2/global warming phoenomenon has been invented and manipulated by journalists and politicians to serve their own agendas ie keeping themselves busy and in a job. Also to stop people in the 3rd world from using fossil fuels to develop their nations - so we can have their oil and coal instead.