To be clear, you'd need to stack them about half a mile high.
I'm not sure what vanity has to do with anything climate related, or the age of the earth for that matter.
Well, "we", if you mean Homo Sapiens, have been around for millennia. It's not exactly a mystery why the area where farming first emerged, once referred to as "The Fertile Crescent", is no longer fertile. Humans have always despoiled the environment and annihilated species. It's what we do best, and it's why we're so successful compared to sabre-toothed tigers, mastodons, and giant sloths, for example
As for the waning glaciers, it's happening now because civilization is burning oil, gas, coal, and jet fuel, not to mention trees, forrests, and other "biomass", at an ever increasing rate, every hour of every day, 365 days a year; year in, year out; decade upon decade. I've never understood why anybody would doubt human-caused global warming. It's just common sense. When you burn shit, it gets hot.