'clean coal' can also mean coal burned without harmful particulates/elements ent...

dbz · on Nov 10, 2016

C02 is one of the worst 'dirty' emissions (methane is worse), and C02 is the most important gas for controlling the earth's temperature - http://earthobservatory.nasa.gov/Features/CarbonCycle/page5....

"The current episode of global warming is attributed to increasing emissions of CO2 and other greenhouse gases into Earth's atmosphere. " - https://en.wikipedia.org/wiki/Carbon_dioxide_in_Earth%27s_at...

Also in the first few lines of wikipedia you will see that C02 is only 0.04% of the atmosphere. This small percentage has huge effects.