On Friday, the sky over Shark Bay in Western Australia turned red ahead of the arrival of Tropical Cyclone Narelle. The phenomenon is largely due to the large amounts of iron-rich dust that the storm brought from the interior of the country.
According to a North American company that provides commercial global weather forecasting services, color change occurred “as dust filled the air prior to the arrival of Tropical Cyclone Narelle”. “No, it is not a filter!”, added the company, quoted by .
“It’s incredibly scary outside and everything is covered in dust“, reads the Facebook post of Shark Bay Caravan Park, caravan park in the area where the phenomenon was observed.
Why did it happen?
The soils of the regions of Australia, whose aenvironment is dry and hotis rich in iron and, suffer from a process of oxidation weathering – name given to chemical process in which the Atmospheric oxygen reacts with minerals in rocks (especially those containing iron), forming oxides and hydroxides – according to the National Environmental Satellite, Data and Information Service, a division of the United States National Oceanic and Atmospheric Administration.
“In this type of environment, these rocks effectively begin to rust,” the service said. “As the rust expands, it weakens the rock and helps break it down.”
Oxidation weathering gives the dust a reddish hue similar to the hue of Mars, explained the National Satellite, Data and Environmental Information Service. This red dust was then spread with the help of cyclone winds.
The phenomenon, also known as “Mie Scattering”happened when sunlight fell on a large number of smoke particles.
Is this the first time?
Although extraordinary, a similar situation occurred in 2019already Jambi province, in the central region of Sumatra, after a series of fires forestry that ravaged the east coast of Australia. Also there the sky ‘woke up’ black and then assumed a forte reddish tone.
Occasionally, the skies also turn red due to passing cyclones, dust storms and forest fires.
Cyclone Narelle arrived in Australia March 20classified as a category 4 hurricaneaccording to AccuWeather, reaching, first, the Cape York Peninsula between the Lockhart River and Coen regions.
After bringing winds and rain to the western part of the Australian continent on Saturday, the The cyclone has been downgraded to a tropical low pressure area, according to the Australian Meteorological Service.
As it crossed the coast of Western Australia on Friday afternoon, the cyclone Narelle became the first storm system in more than 20 years to hit three of Australia’s states and territoriesaccording to the North American meteorological company.
“The last storm that most closely resembled the forecast for the Narelle was Cyclone Bianca, in 2011″, informed the AccuWeather.
