December 2, 2024
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What caused the seven-mile scar in the Australian outback seen on Google Earth?
A man researching Google Earth discovers a mysterious scar in the Australian outback. And now scientists are figuring out why
This Google Earth image shows a mysterious scar carved into Australia’s barren landscape.
The following essay is reproduced with permission. conversationan online publication covering the latest research.
Earlier this year, a cave explorer was poring over satellite images of the Nullarbor Plain when he discovered something unexpected. It was a huge mysterious scar carved into the barren land.
This discovery intrigued scientists, including my colleagues and myself. Upon further investigation, it was determined that the scar was created by a violent tornado that no one knew existed. We provide an overview of the new research results announced today.
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Tornadoes are a known threat in the United States and other countries. But they also happen in Australia.
Without the power of technology, this amazing example of the power of nature would have gone unnoticed. It’s important to study the aftermath of tornadoes to predict and prepare for the next big twister.
Tornadoes are not just a phenomenon in the United States. It can also occur in Australia.
Gray Zone/Alamy Stock Photo
Australian tornado history
Tornadoes are violently spinning columns of air that fall to the ground from thunderstorms and can have wind speeds exceeding 200 kilometers per hour. They can cause massive destruction, uprooting trees, tearing buildings apart, and throwing debris long distances.
Tornadoes have been reported on every continent except Antarctica. It most commonly occurs in the Great Plains region of the United States and northeastern regions of India and Bangladesh.
The first tornado observed by Australian settlers occurred outside Sydney in 1795. However, it was not confirmed by Western scientists that tornadoes occurred here until the late 1800s.
Examples recorded in Australia in recent decades include a 2013 tornado that crossed northeast Victoria and reached the New South Wales state border. It brought winds of 250 to 300 kilometers per hour and caused damage to towns on the Murray River.
And in 2016, severe storms spawned at least seven tornadoes across central and eastern South Australia.
It is important for scientists to accurately predict tornadoes and issue warnings to local communities. That’s why the Nullarbor tornado scar was so useful for research.
swirling mystery
The Nullarbor Plain is a remote, dry, treeless stretch of land in southern Australia. The man who discovered the scar was using Google Earth satellite imagery to search for caves and other karst formations in Narebor.
Karst is a landform characterized by unique topography beneath limestone. The discovery of this scar came to the attention of my colleagues and I through a collaborative network of researchers and explorers studying the Nullarbor karst.
The scars extend from Western Australia across the border to South Australia. It is located 20 kilometers north of the Trans-Australian Railway and 90 kilometers east-northeast of former railway settlement Forrest.
We compared satellite images of the scene over several years and determined that the tornado occurred between November 16 and 18, 2022. A blue circular pattern appeared next to the scar, indicating puddles from heavy rain.
My colleagues and I then visited the site in May of this year to examine and photograph the scar and surrounding landscape.
Our results are Southern Hemisphere Earth System Science Journal.
what we found
The scar is 11 kilometers long and 160 to 250 meters wide. You can see an impressive pattern called the “cycloid mark” formed by the tornado’s suction vortex. This suggests that this tornado was not an ordinary storm, but was in the strong F2 or F3 category, rotating with destructive winds in excess of 200 kilometers per hour.
The tornado probably lasted between 7 and 13 minutes. The characteristics of the scar suggest that the swirling winds within the tornado were moving clockwise. The tornado also appears to have moved from west to east, which is consistent with the direction of a strong cold front in the area at the time.
Cycloid tracks can be seen in the tracks of tornadoes caused by multiple vortices in the Australian outback.
Local weather observations also recorded intense cloud cover and rainfall during that period in November 2022.
Unlike tornadoes that hit populated areas, this one did not cause any damage to homes or towns. But it nevertheless left its mark, eroding soil and vegetation and reshaping the Earth’s surface.
Remarkably, the scars were still clearly visible on satellite images and on the ground 18 months after the incident. This is probably because vegetation grows slowly in this arid landscape and has not yet covered the erosion.
predict and prepare
This fascinating discovery on the Nullarbor Plains shows how powerful and unpredictable nature can be, sometimes without us even realizing it.
Only three tornadoes have ever been recorded on the Nullarbor Plain. This is likely due to the remoteness of the area with few witnesses and the event causing no damage to property or infrastructure. Interestingly, these three tornadoes occurred in November exactly like this one.
Our study provides valuable insight into tornadoes in this remote and little-studied region. This will help you understand when and under what conditions these types of tornadoes occur.
It also highlights the importance of satellite imagery to identify and analyze weather phenomena in remote areas and help predict and prepare for the next big event.
And finally, this result is a stark reminder that extreme weather events can occur anywhere at any time.
This article was first published conversation. please read original article.
