A man spotted the scar while looking at Google Earth satellite imagery earlier this year. Screenshot, Google EarthWhen tornadoes rip through populated areas, their presence is unmistakable. Theyre loud, dangerous and destructive, leaving behind a trail of debris that lingers long after theyre gone. But what about when they sweep across barren, rural land?Even when no one is around to see or hear them, tornadoes still make their mark on the landscape, as researchers in Australia recently demonstrated. By investigating a mysterious scar on the ground, they determined that a powerful tornado swept through the desert two years agobut it went undetected, until now.The findings were published last week in the Journal of Southern Hemisphere Earth Systems Science.Earlier this year, a man was studying Google Earth satellite imagery of a region called the Nullarbor Plain. Located in southern Australia, the Nullarbor Plain is a flat, dry, treeless area that spans the border between the states of South Australia and Western Australia.The man was looking for caves, but he instead spotted a mysterious shape on the ground. It looked like a long, slender line running mostly east-west. The mark wasnt perfectly straightit sloped and curved and, at one point, formed a deep V. It looked a bit like a childs drawing of a seagull, as Peter de Kruijff writes for the Australian Broadcasting Corporation.Eventually, news of the mysterious discovery reached researchers at Curtin University in Perth. After studying historic satellite imagery and weather data for the region, they realized the unusual squiggle on the ground was the calling card of a tornado.Without the power of technology, this remarkable example of natures ferocity would have gone unnoticed, Curtin University geoscientist Matej Lipar, the studys sole author, writes in the Conversation. Researchers studied the looping "cycloidal marks" in the scar to determine the tornado's severity, direction and wind speeds. Matej Lipar, Journal of Southern Hemisphere Earth Systems Science, 2024Lipar and his colleagues determined the tornado had passed through the area sometime between November 16 and November 18, 2022. During that period, a low-pressure system and a cold front occurred in the region, which could have produced severe weather conditions.The team also visited the Nullarbor Plain to see the scar for themselves. It was still thereand clearly visible18 months after the storm. The scar measured 6.8 miles long and spanned between 525 and 820 feet wide. It had cycloidal marks, or a chain of dark loops created by the tornados suction vortexes.Based on their observations, the researchers estimate the tornado was in the F2 or F3 category rated significant or severe, right in the middle of the Fujita Scale of tornado intensityand it likely reached speeds of more than 124 miles per hour. They suspect the tornado lasted for 7 to 13 minutes and was spinning clockwise as it traveled east across the barren landscape.But not everyone is convinced that the scar alone can reveal all that information. Since the tornado didnt damage any buildings and had no witnesses, its difficult to estimate its intensity.F2 and F3 tornadoes certainly occur in Australia, but are comparatively rare and are associated with stronger, longer-lived thunderstorms, John Allen, a meteorologist at Central Michigan University who was not involved with the research, tells the Australian Broadcasting Corporation. But based on the presence ofcycloidal marks, he agrees atornado likely did sweep through the area.The study suggests satellite imagery could be a useful tool for meteorologists, especially those studying remote, uninhabited places. Even in rural areas, researchers want to be able to predict and prepare for severe weather.The findings are also a stark reminder of just how powerful and unpredictable nature can be, sometimes without us knowing, Lipar writes in the Conversation.Extreme weather can strike anywhere, anytime, he adds.Get the latest stories in your inbox every weekday.Filed Under: Australia, Deserts, Earth Science, Geology, Maps, New Research, Satellites, Tornadoes, Weather