It's an idea that most of us would rather not face -- that within the next century, life as we know it could come to an end. Our civilization could crumble, leaving only traces of modern human existence behind. It seems outlandish, extreme -- even impossible. But according to cutting edge scientific research, it is a very real possibility. And unless we make drastic changes now, it could very well happen.

Experts have a stark warning: that unless we change course, the "perfect storm" of population growth, dwindling resources and climate change has the potential to converge in the next century with catastrophic results.
'Earth 2100': the Final Century of Civilization? - ABC News