what are extreme natural events? learning outcomes: 1. understanding the difference between an...
TRANSCRIPT
What are Extreme Natural Events?
Learning outcomes:1. Understanding the difference between an
extreme natural event and a natural
disaster.2. Explain the difference between natural
disasters and other hazards.
3. Identify natural hazards in NZ, Australia & the South-west Pacific
4. Draw and interpret a Venn diagram
Natural eventsCaused by natureOccur frequently in many
environmentsIs a result of a series of
processes.Example: The rainfall process
Extreme natural eventsOccur less frequentlyThey are natural hazards only if
they threaten people’s activities and property
Extreme natural events put people’s actions, property and resources at risk.
They are likely to modify or change environment.
A river after a flood
Examples of Extreme Natural events
Damage after a tornado
Earth quake damage
Damage after a volcano erupted
Human error vs. Extreme natural event
Ballantyne’s fire-possibly caused by electric fault
Napier fire-caused by 1931 earthquake
Important terms:Onset Period-Some natural events build
up more slowly, and give more warning, than others. A tropical cyclone has a much slower onset period than a hailstorm
Duration-Some extreme natural events last longer than others. A drought lasts much longer than an earthquake which may be over in a few seconds.
Frequency-Some extreme natural events occur less frequently than others but cause more damage when they occur.
New Zealand’s Natural hazardsNew Zealand’s environment is largely
mountainous and geologically active. It is surrounded by ocean and lies across a belt of westerly winds. Consequently extreme natural events occur frequently in New Zealand.
New Zealand’s population distribution and cultural processes (eg. farming, urbanisation) expose it to a range of natural hazards.
Natural hazards in New ZealandFlooding EarthquakesVolcanic Eruptions LandslipsTornados Coastal erosion
Bush firesCyclones Blizzards
Thunderstorms Hailstorms Droughts
Australia’s Natural HazardsAustralia’s natural and coltural
environments are different from New Zealand’s
Natural hazards in Australia include droughts, bush fires, tropical cyclones and floods
Different parts of Australia are affected by different natural hazards
South–west Pacific Islands natural hazardsThe islands of the South-west Pacific
have different natural and cultural environments from both New Zealand and Australia.
They have a tropical climate, are surrounded by ocean, and consist mainly of small volcanic islands and coral atolls.
The most common extreme natural events are tropical cyclones, earthquakes, volcanic eruptions, tsunamis and droughts.