Interesting read.
I once wondered what would be the contribution to atmospheric heat of the combustion of cigarettes, and waved it as probably insignificant.
A quick googling suggests burning a cigarette releases 7.8 J/mg of tobacco[1], that a cigarette weighs around 1 g, and that about 5 trillions (5e12) cigarettes are smoked annually [2].
This amounts to 3.9e16 J, or, averaged over one year, 1.2e9 W; corresponding to the total US energy consumption around 1730, according to the figure in parent's link.
Insignificant today, but not a few centuries back.