Carbon dioxide, one of many components of vehicle exhaust, is the same non-toxic gas exhaled by humans. It accounts for 80 percent of greenhouse gases; 98 percent of the atmosphere's carbon dioxide comes from burning fossil fuels.
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Blatently WRONG. 98% of the Earth's CO2 does NOT come from fossil fuels. Almost the opposite is true. This 98% statement is pure, lying ideology, exacerbated by a scientifically ignorant and lazy press. Oh, and CO2 is NOT 80% of greenhouse gas either by mass or volume. The right answer would be water vapor. But then, that would be science, not politics.

-p