Facts about the Australia bushfires. Climate change increases the occurrence and severity of wildfires. Email updates Sign up to receive updates from the field, stories from families we've helped, and ways you can get involved. Sign up now.
Hazards are inevitable — but the impact they have on society is not. Australia is very prone to menacing bushfires. At any time of the year, some parts of Australia suffer extremely damaging bushfires. Have a look below at some facts and numbers about the devastating Australia bushfires. Australia bushfires: Facts and numbers As of 6 January Over million animals died across New South Wales. Officials say 24 people have lost their lives nationwide this fire season.
Explore more. Disasters explained: Earthquakes Powerful earthquakes and landslides can be very deadly. How does climate change affect disasters? Show more. Choose a country: Countries Canada United States. They can occur in forests, grasslands, brush and deserts, and with sufficient wind can rapidly spread. Unchecked, such fires can cause devastation to forests and other areas of vegetation. If fires approach or occur near towns or cities it often prompts a precautionary evacuation, as the direction fires may take are unpredictable.
The most common causes of fires are lightning strikes, sparks during arid conditions, the eruption of volcanoes, and man-made fires arising from deliberate arson or accidents. A side-effect of wildfires that also threatens inhabited areas is smoke. Fires create large quantities of smoke, which can be spread far by wind and poses a respiratory hazard. Satellites can be used to map the extent of a fire by observing the smoke plumes and identifying burn scars.
Thermal infrared sensors can detect heat, thereby pinpointing the exact locations of fires and data acquired through the Charter may be passed on to firefighters on the ground within a matter of hours, providing helpful assistance for their efforts in locating and combating fires. The higher the temperature the more likely it is that a fire will start or continue to burn.
This is because the fuel is closer to its ignition point at high temperatures and pre-heated fuel loads burn faster. Dry air promotes a greater intensity fire than moist air. Plants become more flammable at a low humidity because they release their moisture more easily. Fires pre-heat their fuel source through radiation and convection. As a result, fires accelerate when travelling uphill and decelerate travelling downhill. The steepness of the slope plays an important role in the rate of fire spread.
The speed of a fire front advancing will double with every 10 degree increase in slope, so that on a 20 degree slope, its speed of advance is four times greater than on flat ground.
Bushfires can originate from both human activity and natural causes with lightning the predominant natural source, accounting for about half of all ignitions in Australia. Fires of human origin currently account for the remainder and are classified as accidental or deliberate. Fires lit deliberately can be the result of arson or might be designed to achieve a beneficial outcome but conditions have changed, resulting in uncontrollable spread.
Unfortunately deliberate and accidentally lit fires are more prevalent near populated areas and have a disproportionately higher risk of infrastructure impact. Arsonists place people and property at serious and unnecessary risk, particularly when igniting fires on extreme fire weather days. The Australian climate is generally hot, dry and prone to drought. At any time of the year, some parts of Australia are prone to bushfires.
The widely varied fire seasons are reflected in the continent's different weather patterns. For most of southern Australia, the danger period is summer and autumn.
For New South Wales and southern Queensland, the peak risk usually occurs in spring and early summer. The Northern Territory experiences most of its fires in winter and spring. Grassland fires frequently occur after good periods of rainfall which result in abundant growth that dries out in hot weather. Bushfires tend to occur when light and heavy fuel loads in Eucalypt forests have dried out, usually following periods of low rainfall.
The potential for extreme fire weather varies greatly throughout Australia, both in frequency and severity. When potential extreme fire weather is experienced close to populated areas, significant loss is possible. In terms of the total area burnt, the largest fires are in the Northern Territory and northern areas of Western Australia and Queensland.
Most loss of life and economic damage occurs around the fringes of cities where homes are commonly in close proximity to flammable vegetation. A comparison of disaster cost estimates in Australia. International J of DRR.
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