Why are autumn leaves blown into mini tornadoes on the street?
The answer to this question will leave you in a spin...
Asked by: Jessica Mackin, Banbridge
Buildings shield us from the surprisingly strong airflows that sweep over the land at this time of the year. If these airflows strike buildings, they produce eddies and swirls just like those around a brick stuck in a stream. The resulting vortices can tip over to produce tornado-like swirls – especially around tall buildings in built-up areas.
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Authors
Robert is a science writer and visiting professor of science at Aston University.
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