the definition of a natural disaster
The definition of natural disasters is any catastrophic event that is caused by nature or the natural processes of the earth. The severity of a disaster is measured in lives lost, economic loss, and the ability of the population to rebuild.
Events that occur in unpopulated areas are not considered disasters. So a flood on an uninhabited island would not count as a disaster, but a flood in a populated area is called a natural disaster. All natural disasters cause loss in some way. Depending on the severity, lives can be lost in any number of disasters.