War would see an increase in bitcoins price but a natural disaster? I'm not sure. It depends how many places it affects since if it's just a small country or a few islands it wouldn't affect the price at all even if the people there had to spend all of their bitcoins.
It has a point. People today did not really give attention to bitcoin, some people ises but not all therefore we can conclude that it would not be affected because of the high population a specific location a disaster will come. With this we can say that the market as a whole will not be affected.