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Flashcards in Wildfires Deck (6)
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What are and what are the causes of wildfires?

Wildfires are uncontrolled fires in the wild, they are caused when the fire triangle of oxygen, fuel and heat meet in nature e.g hot, dry weather and dry vegetation and strong winds.

They can have either natural or human causes:
Lightning, Volcanic eruptions, dropped cigarettes, barbecues, fireworks and arson.


What are the three types of wildfire and what conditions can intensify fires?

GROUND FIRES, slow smouldering fire in the ground with little flame and little smoke.

SURFACE FIRES, Where leaf litter and low-lying vegetation burn.

CROWN FIRE, Where fire moved rapidly through the canopy, often intense and fast moving.

Certain conditions can intensify wildfires:

Vegetation type: Some trees such as Pine contain lots of oil and closely spaced trees allow fire to travel easily.

Fuel characteristics: Fine, dry material such as long grass can catch fire and burn most easily.

Climate and recent weather: Rainfall in the past must have been sufficient enough to allow vegetation to grow but more dry recently to allow vegetation to dry up.

Fire behaviour: Fire can burn in different ways e.g creeping fire moves slowly whilst rapid fire moves and spreads quickly.


What is an example of a Wildfire event?

The Black Saturday bushfires were Australia’s worst ever wildfires, from the 7th Of February 2009 the fires burned through the state of Victoria in South-East Australia.


What are some facts about the Black Saturday bushfires?

> Prior to the fires there had been ten years of drought, but above average rainfall (that had since dried up) had been recorded 3 months earlier which had helped the forests bloom and grow to their maximum vegetation before being dried out.
> Recent temperatures had been over 40°c for days and there were very strong winds.
> The government was criticised for its lack of forest management that would have tamed the fires, there was lots of oil rich Forrest litter that had been incorrectly managed.
> Faulty power lines were blamed for the fires.


What were some of the impacts of the fires?

> 173 people died and a further 400 seriously injured.
> 2000 homes were destroyed.
> More than 60 businesses had been destroyed.
> Around 4,300km2 Of land was burnt, millions of animals were killed including thousands of the rare Sooty owl which is now beloved extinct.


What were some of the responses?

>The Australian bureau of Meteorology predicted how the fires would spread and told people to evacuate in the most high risk areas, evacuation prevented many deaths but put the lives of many who stayed at risk.
> More than 20,000 firefighters and volunteers helped to contain the fires and support victims.
> AUS$400 was donated to help build homes for those who had lost them, however fire resistant measures made the homes still highly unaffordable for people.
> Many mitigation recommendations were made such as the construction of fire shelters and improved warning and evacuation procedures.