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> Uranium could power the world as far into the future as we are today from the dawn of civilization—more than 10,000 years ago. Thermodynamics would like to h

> Uranium could power the world as far into the future as we are today from the dawn of civilization—more than 10,000 years ago. Thermodynamics would like to have a word: > […] the Earth has only one mechanism for releasing heat to space, and that’s via (infrared) radiation. We understand the phenomenon perfectly well, and can predict the surface temperature of the planet as a function of how much energy the human race produces. The upshot is that at a 2.3% growth rate (conveniently chosen to represent a 10× increase every century), we would reach boiling temperature in about 400 years. https://dothemath.ucsd.edu/2012/04/economist-meets-physicist/ https://dothemath.ucsd.edu/2012/04/economist-meets-physicist...

Ratalala 3y ago
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. [1] https://www.researchgate.net/publication/307705601_Heat_Emission_from_a_Burning_Cigarette https://www.researchgate.net/publication/307705601_Heat_Emis... [2] https://www.vitalstrategies.org/tobacco-atlas-global-tobacco-users-at-1-3-billion-smoking-among-young-teens-ages-13-15-increases-in-63-countries/ https://www.vitalstrategies.org/tobacco-atlas-global-tobacco...