How Big Is the Atmosphere?

I have looked up a few facts:

• The Earth's atmosphere that can support life extends up about 36,000 feet
• The air gets thinner at increasing atmosphere, and the transition from atmosphere to outer space is gradual and uncertain
• When a spacecraft re-enters the atmosphere, the effects become noticeable around 75 miles up
• The diameter of the Earth varies from about 7926 miles at the equator to 7900 miles at the poles
• You can calculate the volume of the portion of the atmosphere that can support life at 1,343,534,989 cubic miles (which is a whopping 197,765,598,800,000,000,000 cubic feet)
• If you add in the volume of the atmosphere up to the onset of outer space, the volume increases dramatically to 15,034,881,520 cubic miles (or 2,213,103,768,000,000,000,000 cubic feet)
• The number of cars worldwide is just over 1 billion

Why are these facts significant?  I think the amount of CO2 produced by cars is a drop in the bucket compared to the total volume of the atmosphere.  With the atmosphere having only about 0.0397% carbon dioxide, the volume of CO2 is still 878,602,195,900,000,000 cubic feet.  With 1,000,000,000 cars, the amount of CO2 volume in the atmosphere per car is 878,602,196 cubic feet/car.  Do you still think that your car can destroy the earth as the brilliant scientist, Al Gore, tells you over and over?

A complication is that the facts on CO2 produced per automobile per mile is listed in mass or weight rather than volume.  The EPA says that the average car gets 21 mpg.  (I guess that's the US average, because Europeans generally drive smaller, more fuel efficient cars.)  With that average mpg, the average car produces 423 grams per mile of travel, based on a gallon of gasoline producing 8887 grams of CO2 when it is burned.

The density of the air in pounds/cubic foot varies with the altitude.  When the CO2 leaves the tailpipe of the car, what happens to it?  Does it mix in throughout the atmosphere with the earth's rotation creating centripetal force that pushes is out into the atmosphere?  If it is strewn throughout this entire huge volume, 75 miles thick all over the surface of the planet, how can this small amount of CO2 emissions make a significant difference?

If it is significant, why not convert the CO2 to oxygen?  How?  Trees.  Use the billions of dollars spent by our government trying to convince us to stop burning fossil fuels, and grow and plant trees.  I've written it before, and here I am writing it again.  It's time to do something productive for a change.  Stop the MessAPolitico that is killing our economy.