Expert: Dave Russell - 12/2/2006

Question
I would like a breakdown of the sources of carbon dioxide emissions (from non-natural processes--i.e., combustion) in the United States.  What is the total amount of CO2 emissions, and how much comes from each significant source.

The sources would include:

-internal combustion engines for vehicles
-oil fired power plants
-natural gas fired power plants
-coal fired power plants
-natural gas burned in homes and businesses for heating, etc.
-oil burned for heating
-any other significant sources

Also, for perspective, I would like to know the amount of CO2 produced in the US by natural processes, such as respiration of animals, forest fires, etc.

Answer
Rather than waste space and time in providing an answer that I would have to look up, let me point you to the source for data, I would use to answer your question.
http://www.eia.doe.gov/environment.html
That should provide your base answer.
The other sources (natural) are a bit of a puzzlement. The problem is there are only very rough estimates. The figure I've seen in a couple of places is that the total of manmade emissions (fuel related) represents about 82% plus or minus of the total of US emissions of CO2.  I cannot vouch for the figure or it's accuracy.  However, one source appears to be http://www.eia.doe.gov/oiaf/1605/gg98rpt/carbon.html
Good luck
Hope that helps.