Aliens, David? Please. Don't be silly. The solution is simple. We allow the Israelis to ethnically cleanse all the Palestinians a bit quicker. Then "The Rapture" comes and Jesus saves us all. Problem solved!
Apocolyptic sarcasm aside, I think the odds are almost insurmountable that we survive as a species.
I've run my company very sustainably for about 15 years. Went vegan 5+ years ago. Got rid of the 2d car 3+ years ago. Had only 1 kid. Vote and support NGOs to affect change as much as we can.
My wife and I are enjoying these years while they last, and hope that we are pushing up daisies before the shit really hits the fan.