Natural Hazards? 1. A natural disaster (physical event)  volcanic eruption  Earthquake  Landslide 2. Human activity  Ex: coastal settlement of populations

Basically….. A natural disaster is a naturally occurring event/phenomenon that has an effect on people

Vulnerability  Vulnerability = susceptibility to injury or attack  Human vulnerability leads to financial, structural, and human losses.  Natural disasters only occur in inhabited areas  A natural disaster in an uninhabited area has little tangible impact on people  Natural disasters are increasing because of…  Population growth (more people)  Urbanization (lots of people in small spaces)  alteration of the natural environment (manmade islands)

Disasters Human Costs  Every year natural disasters leave…  4,000,000 homeless  46,000 injured  5520 dead  These figures do not include the tsunami in Asia (273,000) and Hurricane Katrina (1000) and the Haiti earthquake and…… Source: The International Red Cross

Positive Effects  natural disasters have beneficial ecological consequences.  rejuvenation of a coniferous forest months and/or years after fires  recharging of groundwater stocks after a flood).  benefits tend to become apparent months or years after an extreme event

Methods of Classification  Calculating human costs  Impact measured by:  loss of life (total deaths)  number of injuries  damage to property (replacement costs)

Methods of Classification  Strength/size/intensity of event  Hurricane system  Tropical depression, tropical storm, category 1-5  Tornado scale  Force 1-5  Richter scale (seismic events)  Scale of 1-9, with 9 being cataclysmic, worldwide event  Epidemic, pandemic

Methods of Classification  Regional occurrence  Hurricane (Atlantic)  Typhoon (Pacific rim)  Monsoon (Asia, Africa)  Frequency of occurrence  Annually?  Centenially?

Disaster Categories  We classify natural disasters by the chief process or sphere in which it operates  Ex: Atmosphere, biosphere, lithosphere  This system has three categories

Atmospheric Hazards Cyclonic Storms (hurricane, typhoon, cyclone) Tornado (twisters, dust devils) Severe Storm (White Juan, Nor’easter) Flooding (heavy rains) Drought (lack of rain, prolonged high pressure) Wildfire (wind, lightning) Severe Weather (hot/cold) ex: ice storm

Biological Hazards Infectious Disease  HIV, H1N1, Bubonic Plague) Parasitic Disease  ringworm Insect Infestation  malaria, West Nile virus Plant Disease  Dutch Elm disease, blight

Geological Hazards Slide (mud, land, rock) Volcanic Activity Earthquake Avalanche Tsunami (tidal wave)

Comparison and Analysis  Any one disaster can be described by analyzing various factors that determine how great an impact it will have on people  This system recognizes six main factors

Comparison and Analysis 1. Frequency  how often is the event likely to happen 2. Duration  the length of time the event lasts 3. Extent  Size of area or region affected  Town? Continent? Region?

Comparison and Analysis 4. Speed of onset 4. sudden, without warning, over quickly? 5. build slowly before a peak period 5. Spatial dispersion  area likely to be affected by a particular event 6. Temporal spacing  how hazards and disasters occur in time; are they random or do they occur within a cycle