What is a Hazard?A natural hazardoccurs at theintersection of humanactivity and a naturalevent.
According to the EM-DAT internationaldatabace, a natural hazard becomes adisaster when one or more of the followingoccurs. 10 + people are killed 100 + people are affected A state of emergency is declared International assistance is called for.
Dregg’s disaster modelDefines a disaster asopposed to a NaturalHazard.
How would you categorise the following hazards?
Hydro- Geo-physical Extra-terrestrialmeteorologicalAre there any hazards that do not easily fit into these three categories?
Some hazards are sogreat that they havethe potential to affectthe entire planet.These are calledContext Hazards.Anthropogenic GlobalWarming is anexample of a contexthazard.
Remember that hazards can interact. The interaction of hazards can complicate the categories. One hazard can sometimes set off another (eg. heavy rain can lead to a geo-physical hazard - landslides) Global Warming is particularly complicated with regards to the consequential effects - more about that later.
Hazard profilesUsed to describe the key features of a hazard. Hazardprofiles for volcano in Hawaii (Kilauea) and the IndianOcean Tsunami shown.
Now create your own copy of the hazard profile andchoose at least three hazards you are familiar with to‘map’ on the profile. Remember to use a ruler!
Remember...Risk = hazard x vulnerability capacity to cope
KeywordsContext hazard: Widespread (global) threat due to environmental factors such asclimate changeGeophysical hazard: A hazard formed by tectonic/geological processes(earthquakes, volcanoes and tsunamis)Hazard: A perceived natural event which has the potential to threaten both life andpropertyHydro-meteorological hazard: A hazard formed by hydrological (floods) andatmospheric (storms and droughts) processesVulnerability: A high risk combined with an inability of individuals and communitiesof copeDisaster: A hazard becoming reality in an event that causes deaths and damage togoods/property and the environmentRisk: The probability of a hazard event occurring and creating loss of lives andlivelihoods
Where do hazards occur?This map shows deaths from hazards from theperiod 1975-2004. (worldmapper.org)