9. Consequences of disasters

Hazardous process of all types can have primary, secondary, and tertiary effects:

1. Primary effects occur because of the process itself. For example, water damage during a flood or collapse of buildings during an earthquake, a landslide, or a hurricane.

2. Secondary effects occur only because a primary effect has caused them. For example, fires ignited because of earthquakes, disruption of electrical power and water service because of an earthquake, a flood, or a hurricane, or flooding caused by a landslide into a lake or a river.

1.2. Technological (or man-made) hazards are events that are caused by humans and occur in or close to human settlements [33]. Man-made disasters are less complicated and occupy smaller areas making them easier to control [35]. Table 2 shows the man-made disasters

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Hazards that arise suddenly, or whose occurrence cannot be predicted far in advance, trigger rapid-onset disasters. Earthquakes, cyclones and other windstorms, landslides and avalanches, wildfires, floods, and volcanic eruptions are usually categorized as rapid-onset events. The warning time ranges from seconds or at best a few minutes in the case of earthquakes and many landslides, to several days in the case of most storms and floods. Some volcanic eruptions may be preceded by weeks or months of activity, but predicting volcanoes' behavior remains very difficult and the warning time for the erup-

Most discussion of slow-onset disasters concentrates on one hazard: drought. It can take months or sometimes years for the results of drought to become disastrous, in the form of severe water and food shortages and, ultimately, famine. Other examples are pollution of the environment, and human activities that degrade the environment and damage ecosystems (deforestation for instance) also contribute to disasters. Their cumulative impact may not be felt for decades, although the hazards that they make more likely, such as flash

tion itself may be only days or hours. Most disasters are rapid-onset events [37].

floods and landslides, may be sudden-onset events [37].

Table 2. Classification of technological (man-made) disasters.

with its subgroups and examples [36].

2. Classification based on the speed of onset

2.1. Rapid-onset disasters

2.2. Slow-onset disasters

3. Tertiary effects are long-term effects that are set off because of a primary event. These include things like loss of habitat caused by a flood, permanent changes in the position of a river channel caused by flood, crop failure caused by a volcanic eruption, and so on [31].
