Hi all, first post ever. Sorry if this has already been discussed.
So I’m walking down the street and I see something I’ve seen a few times in my life, which is when a pile of leaves/dust/debris suddenly form into a mini tornado on a windy day. The leaves come off the ground, spin around centralized point (eye?) and it eventually subsides. I’ve looked online and I guess it closest description would be a “dust devil” but I don’t live in the desert and it’s no where near the magnitude.
Assuming everyone here knows what I’m referring to, my question is:
Are these windy occurrences actually the same atmospheric phenomena as actual tornados? Assume is has something to do with air pressure, but don’t know.
In: Earth Science
Small leafy whirlwinds are not the same phenomenon as huge tornadoes. I mean, physically they are both spinning air, but tornadoes are driven by hot air rising at the center and cold air falling at the periphery. This inwards sucking at ground level causes a rotation due to the Coriolis effect, which causes a self-feeding cycle creating more and more spin until the spin force and the pressure differential force almost cancel out. This continues until the pressure differential runs out.
Little whirlwinds during a breeze corm because the breeze gets redirected as it hits objects, forming vortices. Vortices are pretty common when any fluid flow (air is a fluid in the physics sense) gets redirected at high speed.
You don’t _have_ to live in the desert to get dust devils, they are just more common in deserts. They do need a sunny day without much wind though…air near the ground needs to heat up to be warmer than overlying air, then start rising up through the overlying air. And you can’t always see the whole thing, especially if the ground isn’t, well, dusty. Sometimes it’s just the bottom portion that you can see because debris are moving in it.
So you might have still seen a dust devil. Or maybe not, sometimes whirlwinds are just eddies in wind flow.
Latest Answers