Residents along Australia's east coast awoke in the morning to an orange sky as winds swept millions of tons of red dust from the country's inland and dumped it on Sydney. Tanya Ferguson,living in Sydney,saw that the room was completely orange.She thought there was a bush fire.But when she went outside,the entire city was covered in a film of orange dust. "It was like being in the outback ,but it was right here in the city,"she said On that day,a big dust storm swept through Sydney.It covered the city in orange dust for about eight hours,making landmarks such as the Sydney Opera House and Harbor Bridge invisible. The storm affected the transportation system.Flights were delayed.Roads were busy as drivers struggled in the difficult conditions.Children and the elderly were told to stay indoors until the dust had cleared.Later strong winds blew it out to the sea and up the coast. No one was hurt in the storm,though health officials answered hundreds of calls from people with breathing difficulties.Emergency services responded to hundreds of calls about tree branches brought down by strong winds. Dust storms are common in the Australian outback,where the land is arid .But the storms rarely reach the coastal regions. Officials said it was the worst dust storm of the past 70 years.Air pollution levels were 15,500 micrograms of pollutants per cubic meter. "On a clear day the pollutants are around 10--20 micrograms per cubic meter,"said Chris Eiser of the NSW department of the environment. Experts said that dry conditions in the outback and strong winds caused the sandstorm. "Ten very dry years over inland southern Australia and very strong winds have combined to produce the storm,"said Nigel Tapper,an environmental scientist at Monash University, Australia. Which of the following is TRUE?
The dust storm didn't blow up to the coastal regions of Australia. The level of air pollution was very high due to the dust storm. People called the emergency service because they had got lost. Children stayed indoors for the schooling had been cancelled.