Optional Theme

Hazards and Disasters-Risk Assessment and Response

From the spec…• Environmental hazards exist at the interface between

physical geography and human geography. Natural hazard events are often exacerbated by human actions, although conversely, human induced hazard events are also affected ‑by natural environmental conditions. The principles involved in studying natural hazards are identical to those involved in studying human induced hazards.‑

• The focus of this optional theme is on the full range of human adjustments and responses to hazards and disasters at a variety of scales. The term “natural disaster” is deliberately avoided in this theme because it is not considered to be an accurate reflection of the multitude of underlying reasons that expose people to risk and subsequently create the pre conditions necessary for a ‑disaster to occur.

Hazards

• Hurricane Tsunami• Drought Flood• Earthquake Wildfire• Volcanic Eruption Disease Epidemic• Lightening HIV / AIDS• Avalanche Radioactive Leak • Tornado Chemical Explosion • Landslide

Research the following characteristics:• Geophysical process [Tectonic, Geomorphological,

Atmospheric, Biological, Not Geophysical] • Duration of impact [Instant, seconds, minutes,

hours, days, months, years, decades] • Length of forewarning [Seconds, minutes, hours,

days, months, years, decades] • Spatial occurrence [At one extreme global ...] • Scale of impact [Local, Regional or International] • Frequency [between events of a similar

magnitude] • Predictability [easiness of prediction- random or

consistent]

Hazard Characteristics

FREQUENCYFrequent Rare

DURATION OF IMPACT Instant Decades

LENGTH OF FOREWARNING Seconds Decades

SCALE OF IMPACTLocal International

SPATIAL EXTENTLocalised Global

PREDICTABILITYRandom Consistent

Earthquake, Volcanic Eruption, Hurricane, Chemical Explosion.

Hazards

EXTREME NATURAL EVENT

Hazards

VULNERABLE POPULATION

VULNERABLE POPULATION

NO INTERACTION = NO HAZARD

VULNERABLE POPULATION

SMALL INTERACTION = SMALL HAZARD

LARGE INTERACTION = LARGE HAZARD

VULNERABLE POPULATION

Draw Venn diagrams for these events:

• A moderate landslide occurring on an uninhabited island.

• A magnitude 8.1 earthquake occurring near to a city with a population of 18 million people which sits upon an old lakebed.

• A magnitude 6.5 earthquake with it's epicentre in a sparsely populated area, 40 km from the nearest town, in the country ranked 12th in terms of the Human Development Index.

Use the official IBO Spec to define:

• Hazard• Disaster• Hazard Event• Risk• Vulnerability