Natural hazards such as earthquakes, landslides, floods, volcanic
eruptions, tsunamis, and hurricanes cause environmental, economic as
well as sociological problems worldwide. In recent years, greater
availability of information and sensational media reports of natural
hazard occurrence -and in particular in terms of property damage or loss
oflife caused by these hazards -resulted in an increase of hazard
awareness at a societal level. This increase in public awareness has
often been misconstrued as an indication that natural hazards have been
occurring more frequently with higher magnitudes in recent
years/decades, thus causing more damage than in the past. It is still
under debate, however, to which extent recent increases in damage can be
related to changing frequencies of natural processes, or whether
catastrophic events occur at similar rates as they always had. If the
latter is the case, the reason for a greater damage can be related to
dramatic population growth over the last century, with a substantial
augmentation of population density in some regions. Indeed, the
implications are more server in underdeveloped and developing countries,
where urbanisation has increasingly occurred in hazard prone areas such
as coastal zones, alluvial river plains and steep slopes, thus causing
an increase in the exposure to natural hazards. Some groups of society
in wealthy countries accept higher risks in order to live directly on
top of a cliff or on a steep slope to enjoy panoramic views of the
landscape.