The video of the dust devil that formed at the playground of Bhavans Vidya Mandir, Thrissur was shot by Usha Pisharody, a teacher in the school.
How Do Dust Devils Form?
These small, rotating columns of air can result from a mini-weather system that occurs when onepiece of ground heats up faster than the ground surrounding it on a hot, calm, dry day. The American Meteorological Society says it is a well-developed dust whirl; a small but vigorous whirlwind, usually of short duration, rendered visible by dust, sand, and debris picked up from the ground.
Ajit Kumar from Kerala IMD said that the video resembles a tornado or a twister, however it does not seem destructive. It seems to have occurred because of the increase in temperature. The wind pressure gets concentrated in one particular area and forms a column of rotating dust. I have not seen anything of this sort in Thrissur.
â€śWhen the temperature raises, hot air converges and raises like a thin column and rotation gets amplified. The air accelerates in the vertical and is similar to the Ballerina's twirl,â€ť Prof. G.S. Bhatt, Center for atmospheric and oceanic science, IISc
Dust devils range in width from about 10 feet to 100 feet, according to the American Meteorological Society, with an average height of about 650 feet.
Dust devils occasionally are strong enough to cause minor damage (up to F1 on the Fujita scale).