Lecture 2: Natural Hazard Concepts Flashcards
Natural disaster
An extreme event triggered by destructive forces occurring in nature that causes significant disruption to society
Rapid process, limited areal extent
People are unprepared
Includes EQ, forest fires, droughts
Natural catastrophe
Has more global implications, go across national borders, countries and oceans are effected
2004 Indonesian Tsunami
Natural hazard
Any natural process that threatens human life or property
Not directly anthropogenic (shouldn’t have started by an individual)
Process itself is not a hazard, only if threatening
Types of hazards (2)
- Catastrophic hazard
2. Hazardous conditions
Catastrophic hazard
Sudden onset
Occur without much warning
Loss of life, damage to property
Hazardous conditions
Occur slowly
Not necessarily with loss of life
Property damage and long-term health issues (ie. asbestos, radon)
Vulnerable
Exposure to being harmed or damaged
Risk
Product of the probability of a hazardous process and its possible consequences (death, injury, damage)
risk = vulnerability x hazard probability
Acceptable risk
Level of risk that can be tolerated before action is needed to reduce exposure to the process
Hazard assessment
Evaluation of the possibility and/or probability that a threatening process can or will occur
Numerical and physical models
Does not attempt to quantify risk
Risk analysis
Evaluation of the probability of a hazardous process and its possible consequences (the vulnerabilities: death, injury, $ damage)
Geological hazards
Volcanoes, geomagnetism, seismicity, tsunamis, , floods, landslides
Climatological hazards
Hurricanes, tornadoes and blizzards, snow avalanches
Multiple condition hazards
Floods, landslides
Extraterrestrial hazards
Impacts
