How can human race survive the next hundred years?

Stephen Hawking, the famous British astrophysicist and best-selling author is asking How can human race survive the next hundred years? He asks:

In a world that is in chaos politically, socially and environmentally, how can the human race sustain another 100 years?

As I write this I saw 18645 answers and no doubt there will be more. There’re all sort of answers. Some suggesting to “get rid or the nuclear weapons” where as others think ‘we’ll go underground or to other planets”.

Recently Hawking was here in Hong Kong and he spoke about finding new homes in outer space for human survival because he thinks some disaster might destroy earth. He says:

It is important for the human race to spread out into space for the survival of the species, Life on Earth is at the ever-increasing risk of being wiped out by a disaster, such as sudden global warming, nuclear war, a genetically engineered virus or other dangers we have not yet thought of.

All this reminds me of Year 2012, Wayne Chen is talking about.