|
Bushfires in Australia are frequent events during the hotter months of the year, due to Australia's mostly hot, dry climate. Each year, such fires impact extensive areas. While they can cause property damage and loss of human 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. For thousands of years, Indigenous Australians have used fire to foster grasslands for hunting and to clear tracks through dense bush. 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. Other major conflagrations include the 1983 Ash Wednesday bushfires, the 2003 Eastern Victorian alpine bushfires and the 2006 December Bushfires. Victoria has seen the majority of the deadliest and largest bushfires in Australia, most notably the 2009 Black Saturday fires, where 173 people were killed, around 2,000 homes and structures were destroyed, towns were gutted, and some, such as Marysville, were destroyed. Global warming is increasing the frequency and severity of bushfires〔"There is a “clear link” between climate change and bushfires, with the current New South Wales fires influenced by a rising frequency of hot, dry days, according to the climate body that had its funding withdrawn by the Coalition government. * * * The Climate Council’s interim findings, drawn from 60 peer-reviewed studies, show climate change is influencing the number of extremely warm days in Australia, as well as prolonged periods of low rainfall."〕 and will lead to increased days of extreme fire danger.〔(【引用サイトリンク】url=http://www.climatecouncil.org.au/bushfire-information/ )〕 == Categories== 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,〔Dowdy Andrew, J. and Graham A. Mills. Atmospheric and Fuel Moisture Characteristics Associated with Lightning-Attributed Fires. Journal of Applied Meteorology and Climatology 52.11 (2012):2025-2037.〕 arcing from overhead power lines, arson, accidental ignition from agricultural clearing, grinding and welding, campfires, cigarettes and dropped matches, machinery, and controlled burn escapes. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Bushfires in Australia」の詳細全文を読む スポンサード リンク
|