Bushfires

What are bushfires?

Basically a bushfire is the combustion or burning of bush, forest or woodland area. Bushfires are natural hazard or natural disaster,  most common in Australia but also occur in many places around the world where there is plenty of wood, plant leaves or forest that can burn.

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Did you know... that bushfires are actually naturally stored solar energy that is out of control? That's because trees convert all that sunlight into oils that get stored in leaves that end up burning like petrol.


Bushfires are also called wildfires, and the US word may include brushfires or forest fires.

Explore more about bushfires clearlyexplained.com including:

Importance of bushfires

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Why are bushfires important ?

There are some obvious reasons for knowing about bush fires:

  • Environmentally bushfires can be important to local ecosystems. eg smoke is sometimes needed for seeds to germinate.
  • Bushfire benefits to the environment and recovery
  • Bushfires can have a economic and emotional effect on people and property directly affected.


Current news about bushfires

Bushfires are frequently reported in the Australian news. Due to the sudden and devasting potential bushfires cause, news broadcasts become important sources of information about bush fires. This is particularly important from a safety perspective.

Here is the ABC online RSS feed to recent Bushfires. Clicking on the links take you directly to the story:

Bushfire smoke viewed from space

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NASA's Aqua satellite detected many bushfires in Wollemi National Park, New South Wales.  The satellite passed over southeastern Australia on Nov. 4 at 03:40 UTC/Nov. 3 10:40 p.m. EST. The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard Aqua satellite has infrared capabilities that can detect heat from the various wildfires. 

Hot spots appears red and smoke appears in light brown. This image showed that many fires and a large area of smoke from the combined fires were occurring in the Wollemi National Park. image: Image: Jeff Schmaltz, NASA Goddard MODIS Rapid Response Team; Caption: Rob Gutro, NASA Goddard Space Flight Center

How do bushfires occur and progress?

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For a bushfire to start there needs to be fuel, in the form of leaves and/or wood and a ignition or flame point.

This ignition can be caused either naturally by a lightning strike, spontaneous combustion or a deliberate/accidental flame.

Australian Bushfires are particularly severe as eucalyptus tree leaves contain large amounts of oil that act much like any oil and burn very fast and hot.

Bushfire tornado

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Occasionally bushfires can create a range of wind vortexes. These can encompass smoke and create tornado looking like structures, some vortexes can form from flame itself. Though these tornados are not of the same type as the US tornado valley variety. 

Fire tornados like other vortexes can vary in strength and intensity. A range of geographically features can influence how they behave. …

History of bushfires

Bushfires have existed for as long as trees have been around. The kind of Australian trees that tend to burn most vigorously evolved millions of years ago to cope with the dry conditions as continental Australia drifted slowly towards the equator. For example is thought that bushfires in Australia really regularly occurred some 60 million years ago

Future of bushfires

Bushfires will continue to play a role in Australia's ecosystem, economy and social, environment development. The ability to predict and to combat or prevent fires that threaten people's homes will be come more critical.

Further scientific research into fire behaviour is likely to provide more defenses against dealing with this natural phenomena.

Animals during bushfires

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Most animals

When a bushfire is approaching or even smoke, any animals such as kangaroos, emus, or goannas ( lizards) would tend to jump or run in the opposite direction. These animals are most likely to escape.

Not all the animals will escape all the time. Sometimes the bushfire might be moving too fast or from several directions.

Birds and insects during bushfires

How bushfires can be beneficial to the environment

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The main benefits of bushfires to the Australian environment are for certain plant species to release their seeds. 

Some plants actually need heat and smoke to release their seeds. This suggests that fires are critical to the successful reproduction of certain plant species.

how the environment recovers after a bushfire

Most eucalypt areas start to recover about 1 month after the fires. …

Backburning in controlling bushfires to prevent spreading

Backburning

Back burning is basically a way of reducing the amount of flammable material during a bushfire by starting a small fire in front of a main fire front. Material that is burnt is unable to burn again. 



 It is called back burning because the small fires are designed to 'burn back towards the fire front'.

Why and how it works

Geographical processes in bushfires

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What is a geographical process exactly? Well it is basically any process that changes the geography of a region.

So in the case of bushfire the geography can sometimes change before, during and after a fire.

There are physical geographic processes.

For example, before a bushfire usually there is a period of drought. Droughts are caused in part by changes in the Earth's climate such as changes in the sea temperature, like El Niño effects.

how can human communities reduce their vulnerability to the negative impacts of the natural event of a bushfire?

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In Australia there are many communities that are near bushfire prone areas.

There are a few ways to reduce vulnerability.

  • creating fire breaks by clearing a section of trees around a town area.
  • removing the fuel of a bushfire from the town area, prune trees.
  • perhaps grow trees that are not so flammable.
  • ensure building codes and laws make houses more fire resistant.

Useful bushfire related links

Here are a list of resources of bushfire information. Including most emergency services around the Australian states. Also included are International related links.

Videos of bushfires


This youtube video shows an example of a grass scrub style bushfire. Notice how the birds, in this case Hawks,  are drawn to the fire. They  are actually  hunting insects  that are escaping the fire. 


Inside a bushfire control centre

Here is an interactive view of the NSW bushfire control centre. There is a wall of 100 video screens showing a variety of information. This is how bush fires are monitored and provide information to the various emergency services. This control room can give advice to where best target resources or organise evacuation plans.

Interactive by Lincoln Archer with Nick Grimm.