Graphical depiction of a red sky, but it many Australians actually saw a red sky as a cyclone approached this weekend.
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Stunning images on social media reminded me of one of my favorite U2 lyrics about a blood-red sky. It wasn’t an alien invasion or the end of the world. It was simply atmospheric science at work. Footage posted from Western Australia showed a creepy, red sky in advance of Tropical Cyclone Narelle. What’s the science behind the red skies of Australia last week?
To answer that question, I asked one of the top dust experts in the world. Tom Gill is a professor at the University of Texas – El Paso. “This is pretty extreme! It’s about the reddest dust levels I’ve ever seen,” he told me in a message. “The dust is red because there is a lot of iron oxide (basically, rust) in the sand and soil of the desert there, and the wind scours it up from the ground into the sky,” Gill went on to say.
Gill has looked at this type of phenomenon in West Texas and found that the higher the wind speeds, the more manganese and iron was present in the dust. What’s going on? He said, “Increased force of the stronger winds could literally scrape more rust off the surface of the grains of desert sand and suspend it into the air.”
There is something about the red skies of Australia that surprised Gill, however. “Dust storms caused by tropical cyclone winds are very rare, because of course there’s usually a lot of rain, but if the strong wind field from a tropical cyclone crosses on the dry side and over a desert, it can create a very heavy dust storm.” It has happened a few times with a few eastern Pacific hurricanes that moved into the southwestern U.S., according to Gill.
Electromagnetic Spectrum, The Visible Range (Shaded Portion) Is Shown Enlarged On The Right. (Photo By Encyclopaedia Britannica/UIG Via Getty Images)
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Because of the way sunlight interacts with these rust-laden dust and soil particles, the longer wavelength colors of orange and red are scattered less, so a reddish color dominates our eyes. It’s very similar to why sunsets and sunrises are so brilliant. The light is traveling across a greater distance and shorter wavelength parts of visible light are scattered. Here in the southern U.S., we often have vivid sunsets or sunrises when African dust from the Saharan region is in the sky, but it is nothing like what we saw in Australia.
TOPSHOT – The afternoon sky glows red from bushfires in the area around the town of Nowra in the Australian state of New South Wales on December 31, 2019. Thousands of holidaymakers and locals were forced to flee to beaches in fire-ravaged southeast Australia on December 31, as blazes ripped through popular tourist areas leaving no escape by land. (Photo by SAEED KHAN / AFP) (Photo by SAEED KHAN/AFP via Getty Images)
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Tropical Cyclone Narelle made landfall in Queensland, Northern Territory, and Western Australia. “It is relatively rare for a storm to make landfall in three Australian states and territories, with the last two being Cyclone Ingrid in 2005 and Cyclone Steve in 2000,” according to NASA.
Dust storms and wildfires have caused such “apocalyptic” scenes in the past, so perhaps The Fixx was on to something when they wrote”Red Skies.”
Cyclone Narelle approaching western Australia in March 2026.
NASA Worldview