Bushfire
145120
225717894
2008-07-15T01:44:33Z
137.92.97.114
/* External links */
{{Refimprove|date=June 2008}}
{{Wildland Firefighting}}[[Image:Backburning.jpg|right|thumb|[[Controlled burn|Backburning]] in [[Townsville, Queensland|Townsville]], [[Australia]].]]
[[Image:Bushfire damage.jpg|right|thumb|Regrowth two years after the bushfire at [[Bogong High Plains|Bogong]], 2003.]]
[[Image:Termite cathedral mounds in a bushfire blackened tropical savanna.jpg|right|thumb|[[Termite]] cathedral mounds in a [[tropical savanna]] blackened by [[Kakadu National Park]]'s annual bushfires.]]
[[Image:Bushfires_Southeastern_Australia.jpg|right|thumb|Smoke from bushfires can cover a large area, as seen here in eastern [[Victoria (Australia)|Victoria]].]]
[[Image:Melb_bush_fire_smoke.jpg|right|thumb|The city of [[Melbourne]] swathed in smoke during the 2006-2007 bushfire season.]]
[[Image:Trappe fg02.jpg|right|thumb|An [[Australian Bustard]] searching for food behind a bushfire.]][[Image:Ladysmith-RFS.JPG|right|thumb|[[Ladysmith, New South Wales|Ladysmith]] [[New South Wales Rural Fire Service|NSW RFS]] fire fighting tanker]]
A '''Bushfire''' is a [[fire]] that occurs in [[The Bush|the bush]] (collective term for [[scrubland|scrub]], [[woodland]] or [[grassland]] of [[Australia]], [[New Zealand]], [[New Caledonia]]). In south east Australia, bushfires tend to be most common and most severe during summer and autumn, in [[drought]] years, and particularly severe in [[El Niño]] years. Subsequently south east Australia is considered one of the most fire prone areas of the world. In the north of Australia, bushfires usually occur during winter (the dry season)<ref>{{cite web| url=http://burarra.questacon.edu.au/pages/seasons.html | title=Monsoonal Climate | accessdate=2006-09-09 | format=html | publisher= Questacon }}</ref>, 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 can cause bush fires too.
==History==
{{Unreferencedsection|date=June 2008}}
The natural fire regime was altered by the arrival of humans in Australia. Fires became more frequent, and fire-loving species — notably eucalypts — greatly expanded their range. It is assumed that a good deal of this change came about as the result of deliberate [[Fire-stick farming|action by early humans]], setting fires to clear undergrowth or drive game.
Plants have evolved a variety of strategies to survive (or even require) fires, (possessing reserve shoots that sprout after a fire, or developing fire-resistant or fire-triggered [[seed]]s) or even encourage fire ([[eucalypt]]s contain flammable oils in the leaves) as a way to eliminate competition from less fire-tolerant species. Many native animals are also adept at surviving bushfires. Many animals become extinct from bushfires destroying their habitat.
==Bushfire control==
===Key Factors affecting bushfires===
• Fuel: Anything that burns is fuel for the fire: litter on the ground (leaves, twigs, rubbish), undergrowth (shrubs, grass, seedlings), trees and other vegetation, structures (such as your house) and any miscellaneous stuff laying about; gas bottles, piles of firewood, tyres, etc. Ladder fuels are low growing (30 cm to 2 meters) vegetation that offers a ladder for the fire to rise to the canopies of trees.
• Weather: Weather is a major contributor to bushfires. The hotter and dryer, the more likely it is for a bushfire to start and spread uncontrollably. High winds will reduce humidity, and cause an already started bushfire to spread more rapidly. Most bushfires start in the afternoon, when it is driest and hottest.
• Topography/slope: The topography of the terrain is a major factor in bushfire behaviour. Generally the fire spreads faster uphill. Conversely, fire going downhill advances more slowly. The superheated air is pushed in front of the fire drying and pre-warming the fuel for ignition. When a fire progressing downhill hits the flat at the bottom of the hill, the height of the flame can quadruple, when the fire hits the undulating slope opposite, the height may quadruple again. In other words, 1 metre flames going downhill can turn into 4 metre flames at the bottom of the hill, and to 16 metre flames starting to climb the next hill. While the height of the flame depends mainly on the height of the fuel, the former stands as a reminder that an innocent looking small bushfire can rapidly change into a life threatening fire.
===Firefighting Methods===
In [[National Park]]s and reserves, bushfire fighting is carried out by [[professional]] staff, such as [[Ranger]]s, Park Workers, Field and Technical Officers, with help from [[volunteer]]s from rural areas. The rural areas have [[Fire fighting|bush fire services]], E.g the [[Country_Fire_Authority|CFA]], largely staffed by volunteers, to help control bushfires. As with large fires on [[public land]] it is common for Parks staff and Rural or Country volunteers to work together on large rural fires. On some occasions [[urban firefighting]] professionals are also called in to assist. As well as the water-spraying trucks commonly used in urban firefighting, bushfire services often own or lease aircraft, particularly [[fire helicopter]]s, that can douse areas inaccessible to ground crews. However, large fires are often of such a size that no conceivable firefighting service could attempt to douse the whole fire directly, and so alternative techniques are used.
Typically, this involves controlling the area that the fire can spread to, clearing [[control line]]s which are areas which contain no combustible material. These control lines can be produced by [[bulldozing]], or by [[backburning]] — setting a small, low-intensity fire to burn the [[flammable]] material in a controlled way. These may then be extinguished by firefighters, or, ideally, directed in such away so that they meet the main fire [[front]], at which point both fires will run out of flammable material and be extinguished.
Unfortunately, such methods can fail in the face of wind shifts causing fires to miss control lines, or because fires jump straight over them (for instance, because a burning tree falls across a line, or burning embers are carried by the wind over the line).
The actual goals of firefighters vary. Protection of life (both the firefighters and civilians) is given top priority, then private property according to [[economic]] and [[social]] value. In very severe fires, this is sometimes the only possible action. Protecting [[house]]s is regarded as more important than, say, machinery sheds, though firefighters, if possible, will try to keep fires off [[farmland]] to protect [[stock]] and fences (steel fences are destroyed by the passage of fire, as the wire is irreversibly stretched and weakened by it). Preventing the burning of publicly owned [[forest]]ed areas is generally of least priority, and, indeed, it is quite common (in Australia, at least) for firefighters to simply observe a fire burn towards control lines through forest rather than attempt to put it out more quickly — it is, after all, a natural process.
The risk of major bushfires can be reduced by reducing the amount of [[fuel]] present. In forests, this is usually accomplished by conducting [[controlled burn]]s — deliberately setting areas ablaze during favourable weather conditions in spring or autumn. Controlled burns can be controversial, both because they can be regarded as tampering with the forest [[ecosystem]], and because serious fires can be started if a control burn gets out of hand. The [[Indigenous Australians|Australian Aborigines]] used controlled burning to encourage new growth of plants.
Contrary to urban understanding of bushfire, rural farming communities are comparatively rarely threatened directly by them. They are usually located in the middle of large areas of cleared, usually grazed, land, and in the drought conditions present in bushfire years there is often very little grass left. However, [[urban fringe]]s often spread into forested areas, and communities have literally built themselves in the middle of highly flammable forests.
On occasions, bushfires have caused wide-scale damage to [[private property]], particularly when they have reached such urban-fringe communities, destroying many homes and causing deaths.
In fire-prone areas, people living in them typically take a variety of precautions. These include building their home out of [[Flame retardant|flame-resistant]] materials, reducing the amount of fuel near to the home or property, constructing [[firebreak]]s, and investing in firefighting equipment.
==Significant bushfires==
===Notable bushfire events===
* [[Black Thursday]] (1851)
* [[Red Tuesday bushfires]] (1898)
* [[Black Friday (1939)|Black Friday bushfires]] (1939)
* [[Black Sunday bushfires]], [[South Australia]] (2 January 1955)
* [[1961 Western Australian bushfires]] (January-March, 1961)
* [[Chatsbury bushfire|Southern Highlands bushfires]] (1965)
* [[1967 Tasmanian fires|Tasmanian "Black Tuesday" bushfires]] (1967)
* [[Northern Sydney bushfires]] (1979)
* [[Ash Wednesday fires|Ash Wednesday bushfires]] (1983)
* [[1994 Eastern seaboard fires]] (1994)
* [[Linton bushfire]] (1998)
* [[Black Christmas (bushfires)]] (2001-02)
* [[2003 Canberra bushfires]] (2003)
* [[2003 Eastern Victorian alpine bushfires]] (2003)
* [[Eyre Peninsula bushfire]] (South Australia 2005)
* [[2006 Central Coast bushfire|Central Coast bushfires (NSW)]] (New Years Day, 2006)
* [[Jail Break Inn Fire|Jail Break Inn Fire, Junee]] (New Years Day 2006)
* [[Stawell New year fire|Victoria]] (December 2005 - January 2006)
* [[Grampians Bushfire|Victoria]] (January 2006)
* [[Pulletop bushfire|Pulletop bushfire, Wagga Wagga]] (6 February 2006)
* [[2006-07 Australian bushfire season]] (September 2006 - January 2007)
* Black Sunday (4th October 2006)
* [[Kangaroo Island Bushfires]] (6 December 2007 - 14 December 2007)
=== Bushfire gallery ===
<gallery>
Image:Gippsland, Sunday night, February 20th, 1898.jpg|A painting depicting the [[Red Tuesday bushfires]] at [[Gippsland]].
Image:Wagga Wagga, Pulleytop bushfire, February 6th, 2006.jpg|The [[Pulletop bushfire]] at [[Wagga Wagga, New South Wales|Wagga Wagga]].
Image:UminaFire1.JPG|One of the blazes of the [[2006 Central Coast bushfires]] on [[New Years Day]], 2006. Photo taken at [[Umina Beach, New South Wales|Umina Beach]].
Image:Smoke_from_fire_near_holbrook_NSW.jpg|Smoke from the bushfire near [[Holbrook, New South Wales|Holbrook]] on [[2 February]] [[2007]].
</gallery>
==See also==
* [[Country Fire Service]] (South Australia)
* [[Country Fire Authority]] (Victoria)
* [[New South Wales Rural Fire Service]]
* [[Tasmania Fire Service]]
* [[Dead Man Zone]]
* [http://www.nationalparks.nsw.gov.au/npws.nsf/Content/Home NSW National Parks and Wildlife Service]
* [http://www.dse.vic.gov.au/dse/index.htm Victorian Dept of Sustainability and Environment]
* [http://www.environment.act.gov.au/bushparksandreserves/parksandreserves/canbnaturepk ACT Parks Brigade]
== Notes and references ==
{{reflist}}
== External links ==
* [http://www.aus-emaps.com/hotspots.php Bushfire Watch Map] Interactive Google map showing current fire hotspots in Australia and neighbouring countries
* [http://www.timber.net.au/bushfire/ Bushfire Compendium] State requirements for building in bushfire-prone areas
* [http://www.fesa.wa.gov.au Fire & Emergency Services Authority of Western Australia] General Information & Emergency Alerts
* [http://www.rfs.nsw.gov.au New South Wales Rural Fire Service], The NSW [[Rural Fire Service]] is the largest fire department in the world which specialises in fighting bushfires.
* [http://nrfa.fire.org.nz/ New Zealand National Rural Fire Authority Website]
* [http://www.safirefighter.com/ SA Firefighters] A website for South Australian Fire fighters
* [http://www.cfs.org.au/ South Australian Country Fire Service Official Website]
* [http://www.fire-brigade.asn.au/ South Australian CFS Promotions Unit Website]
* [http://www.cfa.vic.gov.au/ Country Fire Authority], Victoria, Australia
* [http://abc.net.au/nature/bushfire/ Bushfire Summer - ABC TV Nature] ABC TV case study of the 2005-2006 bushfire season
* [http://www.iawfonline.org/journal.shtml The International Journal of Wildland Fire]
* [http://www.iawfonline.org The International Association of Wildland Fire]
* [http://www.ewatercrc.com.au/bushfire Bushfires and Catchments] - Effects of Bushfires on Catchments
[[Category:Flora of Australia]]
[[Category:Fire]]
[[Category:Wildfires]]