It depends on the intensity of the disaster. If the disaster destroys all or almost all of the bitcoin server all around the world correct me if I'm wrong with this one, this is how I undertand it at least, then it would produce a significant impact to bitcoin because the supply will decrease and that would result different consequences. And also if internet is paralyzed, there'll be no means to access bitcoin and use it. No interaction, it become useles and if this continues, it will become worthless.