I suspect that Dibert's worse case scenario is about right. Add in a little bit of climate change induced catastrophe and some resource related wars in the next 100 years and the numbers could fly up.
Sadly I got pretty close. What does that mean?
Try This at Home
Let me try a little test with you. I’ll ask you a question, and you answer within 5 seconds. The point is to see how different your first reaction is to the answer you eventually settle on.
Here’s the setup. Imagine a baby born today, who ends up living to the age of 100. Now think about the course of that baby’s hundred years on earth, and answer the following question in five seconds. No cheating. Five seconds.
Question: During that baby’s 100 years of life, how many people will die?
Don’t read on until you have your answer.
I’ll bet your answer was somewhere in the millions.
There are 6 billion people on earth right now, and virtually all of them will die in the next hundred years. Add to that the several billion who will be born during the baby’s life and not be so lucky to live to old age. I think an estimate of 10 billion deaths is entirely reasonable. And that’s if things go well. The worst case is probably 20 billion people.
Is that mind-boggling?