Anyone thinking of entering this essay competition for Year 12 Geographers? Nice open-ended question, and it would definitely fill a big hole in a personal statement! Plus...£600 prize money! You don't have to be thinking of applying to Cambridge - but if you are, it would be an even better idea!
Maybe I'm being over optimistic, but I don't think the human race is going to be entirely wiped out in 100 years...I imagine at the very least, the Richard Bransons of the world could afford to be smugly orbiting in space!
I guess you could either mention a few topics in the intro and then go into detail on the one you see as most important, or try to do a decent couple of paragraphs on several areas. Probably more interesting to go into more depth though...