Looking towards the town Swifts Creek, Victoria, in December 2006 during the Victorian Alpine Fires

Intense bushfires can seriously impact the environment, such as here by the Big River, near Anglers Rest, East Gippsland, after the 2003 Victorian fires

Bushfires in Australia are frequently occurring events during the hotter months of the year due to Australia's mostly hot, dry climate. Large areas of land are ravaged every year by bushfires, which also cause property damage and loss of life.

Certain native flora in Australia have evolved to rely on bushfires as a means of reproduction and fire events are an interwoven and an essential part of the ecology of the continent. In some eucalypt and banksia species, for example, fire causes seed pods to open, which allows them to germinate^{[citation needed]}. Fire also encourages the growth of new grassland plants. Other species have adapted to recover quickly from fire.

For many thousands of years, Indigenous Australians people have used fire for a variety of purposes. These included the encouragement of grasslands for hunting purposes and the clearing of tracks through dense vegetation.

Major firestorms that result in severe loss of life are often named based on the day on which they occur, such as Ash Wednesday and Black Saturday. Some of the most intense, extensive and deadly bushfires commonly occur during droughts and heat waves, such as the 2009 Southern Australia heat wave, which precipitated the conditions during the 2009 Black Saturday bushfires in which 173 people lost their lives.

Definition[link]

Bushfires in Australia, are generally defined as any uncontrolled, non-structural fire burning in a grass, scrub, bush or forested area. Australia, being a geographically and meteorogically diverse continent, experiences many types of bushfires. Fires can be divided into two main categories, depending on topography of the area.

• Hilly/mountainous fires - Burn in hilly, mountainous or alpine areas which are usually densely forested. The land is less accessible and not conducive to agriculture, thus many of these densely forested areas have been saved from deforestation and are protected by national, state and other parks. The steep terrain increases the speed and intensity of a firestorm. Where settlements are located in hilly or mountainous areas, bushfires can pose a threat to both life and property.

• Flat/grassland fires - Burn along flat plains or areas of small undulation, predominantly covered in grasses or scrubland. These fires can move quickly, fanned by high winds in flat topography, they quickly consume the small amounts of fuel/vegetation available. These fires pose less of a threat to settlements as they rarely reach the same intensity seen in major firestorms as the land is flat, the fires are easier to map and predict and the terrain is more accessible for firefighting personnel. Many regions of predominantly flat terrain in Australia have been almost completely deforested for agriculture, reducing the fuel loads in these areas.

Common causes of bushfires include lightning, arson, accidental ignition from agricultural clearing, campfires, cigarettes and dropped matches, machinery, and controlled burn escapes.

Looking towards Dargo, Victoria from Swifts Creek, 11 January 2007

History[link]

Epicormic shoots sprouting vigorously from epicormic buds beneath the thick bushfire damaged bark of a Eucalyptus tree – one of the strategies evolved by plants to survive bushfires

Bushfire damage to forests in East Gippsland, Victoria from the Bogong Fire Complex of 2003, two years after fires swept through the area, showing the recovery of trees and undercroft

The natural fire regime in Australia was altered by the arrival of humans.^{[citation needed]} Fires became more frequent, and fire-loving species—notably eucalypts—greatly expanded their range.^[1] It is assumed that a good deal of this change came about as the result of deliberate action by early humans, setting fires to clear undergrowth or drive game.^[2]

Plants have evolved a variety of strategies to survive (or even require) bushfires, (possessing epicormic shoots or lignotubers that sprout after a fire, or developing fire-resistant or fire-triggered seeds) or even encourage fire (eucalypts contain flammable oils in the leaves) as a way to eliminate competition from less fire-tolerant species.^[3]

Some native animals are also adept at surviving bushfires.^{[citation needed]}

Warnings[link]

In 2009, a standardised Fire Danger Rating (FDR) was adopted by all Australian states. During the fire season the Bureau of Meteorology (BOM) provides fire weather forecasts and by considering the predicted weather including temperature, relative humidity, wind speed and dryness of vegetation, fire agencies determine the appropriate Fire Danger Rating.^[4] In 2010, following a national review of the bush fire danger ratings, new trigger points for each rating were introduced for grassland areas in most jurisdictions. See for example the following glossary ^[5]

Fire Danger Ratings are a feature of weather forecasts and alert the community to the actions they should take in preparation of the day. Ratings are broadcast via newspapers, radio, TV and on websites.

Regional management[link]

The Australasian Fire Authorities Council (AFAC) is the peak body responsible for representing fire, emergency services and land management agencies in the Australasian region.

New South Wales[link]

The New South Wales Rural Fire Service (RFS) is a volunteer-based firefighting agency and statutory body of the Government of New South Wales.^[6]

South Australia[link]

The Country Fire Service is a volunteer based fire service in the state of South Australia.

Victoria[link]

Major bushfires in Victoria in the 2000s

In Victoria, the Country Fire Authority (CFA) provides firefighting and other emergency services to country areas and regional townships within the state, as well as large portions of the outer suburban areas and growth corridors of Melbourne not covered by the Metropolitan Fire Brigade.^[7]

Western Australia[link]

The Fire and Emergency Services Authority of Western Australia (FESA) and the Department of Environment and Conservation (DEC) have joint responsibility for bushfire management in Western Australia.^[8] FESA is an umbrella organisation supporting the Bush Fire Service, Emergency Services Cadets, Fire and Rescue Service, State Emergency Service, Volunteer Emergency Service, Volunteer Fire Service, Volunteer Fire and Rescue Service and the Volunteer Marine Rescue Services.

Seasonality[link]

Bushfires in Australia can occur all year-round, however the severity and the "bushfire season" varies by region.^[9] These seasons are commonly grouped into years such as "2006-07 Australian bushfire season" and typically run from June one year until May the next year.

In south east Australia, bushfires tend to be most common and most severe during summer and autumn (December–March), in drought years, and particularly severe in El Niño years. Southeast Australia is fire prone, and warm and dry conditions intensify the probability of fire.^[10] In the north of Australia, bushfires usually occur during the dry season (April to September),^[11] and fire severity tends to be more associated with seasonal weather patterns. In the southwest, similarly, bushfires occur in the summer dry season and severity is usually related to seasonal growth. Fire frequency in the north is difficult to assess, as the vast majority of fires are caused by human activity, however lightning strikes are as common a cause as human ignited fires and arson.

Major bushfires in Australia[link]

Bushfires have accounted for over 800 deaths in Australia since 1851 and the total accumulated cost is estimated at $1.6 billion.^[12] In terms of monetary cost however, they rate behind the damage caused by drought, severe storms, hail, and cyclones,^[13] perhaps because they most commonly occur outside highly populated urban areas.

Some of the most severe Australian bushfires, in chronological order, have included:

See also[link]

• Wildfire
• McArthur Forest Fire Danger Index

References[link]

External links[link]

Wikimedia Commons has media related to: Bushfires in Australia

• "Bushfires overview". CSIRO. http://www.csiro.au/science/Bushfires.html. 
• "Australian fire risk and season maps". Romsey Australia. http://home.iprimus.com.au/foo7/firesum.html.