I'd consider 9% of all human emissions[1] to be a "major source". Just because it's not the majority doesn't mean it's not important. [1] https://www.epa.gov/g

I'd consider 9% of all human emissions[1] to be a "major source". Just because it's not the majority doesn't mean it's not important. [1] https://www.epa.gov/ghgemissions/sources-greenhouse-gas-emissions https://www.epa.gov/ghgemissions/sources-greenhouse-gas-emis...