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The 2009 Australian dust storm, also known as the Eastern Australian dust storm, was a dust storm that swept across the Australian states of New South Wales and Queensland from 22 to 24 September. The capital, Canberra, experienced the dust storm on 22 September, and on 23 September the storm reached Sydney and Brisbane. Some of the thousands of tons of dirt and soil lifted in the dust storm were dumped in Sydney Harbour and the Tasman Sea. On 23 September, the dust plume measured more than in width and in length and covered dozens of towns and cities in two states.〔(Largest dust storms in 70 years cover Sydney ) ''The Daily Telegraph''〕 By 24 September, analysis using MODIS at NASA measured the distance from the northern edge at Cape York to the southern edge of the plume to be 3,450 km. While the cloud was visible from space, on the ground the intense red-orange colour and drop in temperature drew comparisons with nuclear winter, Armageddon, and the planet Mars.〔 The dust storm was described by the Bureau of Meteorology as a "pretty incredible event" that was the worst in the state of New South Wales in nearly 70 years.〔〔 The phenomenon was reported around the world. The Weather Channel's Richard Whitaker said: "This is unprecedented. We are seeing earth, wind and fire together".〔 ==Cause== Air particle concentration levels reached 15,400 micrograms per cubic metre of air. Normal days register up to 20 micrograms and bushfires generate 500 micrograms. This concentration of dust broke records in many towns and cities. The CSIRO estimated that the storm carried some 16 million tonnes of dust from the deserts of Central Australia, and during the peak of the storm, the Australian continent was estimated to be losing 75,000 tonnes of dust per hour off the NSW coast north of Sydney.〔Leys, J., Heidenreich, S. and Case, M. 2009. DustWatch interim report 22–23 September. DustWatch is funded by the Lower Murray Darling, Lachlan, and Murray CMAs, the Department of Environment, Climate Change and Water NSW and Griffith University.〕 The dust storm coincided with other extreme weather conditions which affected the cities of Adelaide and Melbourne. The dust is believed to have originated from far-western New South Wales and north-east South Australia. This includes an area known as the 'Corner Country', a dry, remote area of far-western New South Wales. In South Australia the dust may also have come from Lake Eyre Basin or the Woomera area, the latter raising concerns that it was radioactive and dangerous since the area contains the Olympic Dam uranium mine.〔 According to the New South Wales regional director of the Bureau of Meteorology, Barry Hanstrum, the cause was an "intense north low-pressure area" which "picked up a lot of dust from the very dry interior of the continent".〔 Senior forecaster Ewan Mitchel said winds from a cold front picked up dust from north-east South Australia on 22 September.〔 That night the winds strengthened to 100 km per hour and collected more dust from areas in New South Wales that were drought affected.〔 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「2009 Australian dust storm」の詳細全文を読む スポンサード リンク
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