This encyclopedia is a descriptive, illustrated account of disasters, both natural and human-induced, that have occurred throughout the world at different times over the past two thousand years. They include experiences of earthquakes, tsunamis, volcanic eruptions, floods, extremes of weather, droughts, pandemic illnesses, land subsidence and landslides. Most troubling of all is a newcomer to the world of disasters, the terrorist attack. While terrorists have, from time to time in the past, wrought havoc on human environments, the expanded volume and brutality of their activities over the past thirty years has gone beyond all previous acts of violence. Terrorism is the type of disaster that may become increasingly destructive in the future.
Sometimes disasters are so named if a large number of people are killed. At other times, the criteria is the amount of damage done to homes and other structures. A third identifying characteristic is the long-term consequences of the event. In this encyclopedia, disaster events have been selected on the bases of all three of these characteristics. A calamitous event that occurred at a given point in time is selected if it caused great damage, significant loss of life, and carried important consequences for subsequent years. The majority of the events included are natural disasters such as earthquakes, floods, and volcanic eruptions because, for the better part of the past two thousand years, catastrophes of this kind were the costliest and deadliest in human experience. Natural disasters were also, and still are, highly unpredictable, so there are good reasons to study them and so continue the search for answers to their predictability.