John McPhee
pgleick | March 27, 2017[An early version of this essay was originally published on my Forbes blog in 2012. It has been edited and updated.]
Geologic time scales are long – far too long for the human mind to easily comprehend. Over millions, and tens of millions, and hundreds of millions of years, the Earth has changed from something unrecognizable to the planet we see on maps, plastic globes, and photos from space. The Atlantic Ocean didn’t exist eons ago and it will literally disappear in the future as the continental plates continue to shift inch by inch. A visitor from outer space millions of years ago would…