What causes a "Dust Devil"?

Question

A dust devil is common around the southwest of US. It's like a small tornado. but it's very, very small. and doesn't have the force to tear up buildings. just enough to fly trash 200 feet in the air. what causes it?

Answer 1

The same processes the create a tornado creates a dust devil. It's hot air rising, as the air rises it pulls in air from around it to fill the void. Now is could be warm air on the surface or it could be a lot of warm air high above you. As the air is pulled to the center it's stats to swirl, and bingo a dust devil is born. When the air rises enough that it find equilibrium then the dust devil dies. You will often see tiny dust devils in a corner where two buildings meet like an inside corner of a L, and if the inside of the L is facing the sun it will heat up. As the sun heats the building the energy is transfered to the air and as the air heats up rises and a little dust devil forms. Now lastly warm air rises because just like water and most other materials when you heat something up is density is reduced. And it become lighter as it is lighter is floats on top of the colder air. Just like the little air bubbles the rises out of your soda.

~D

Answer 2

Basically just the blowing of wind. It sorta gets caught up in a wave pattern that simply repeats upon itself rather than expanding outward...just like when water drains it doesn't always produce a whirlpool..but sometimes it does. Since wind blows in a wave pattern it is very easy for the gusts of wind to pick up debris. The debris is heavier than the force of the air current can sustain and thus will be expelled into the air after a short period of time. If there is another wave of air then the object can be twirled around numerous times before it is released. The remaining force that accompanies the object propels the object in a straight line in whatever direction the object was catapulted. The throwing of the object is the result of centrifugal force.

Answer 3

Dust devils form in areas of strong surface heating and usually occur under sunny skies and light winds, when the ground can warm the air to temperatures well above the temperatures just above the ground.
Once the ground heats up enough, a localized pocket of air will quickly rise through the cooler above it. The sudden uprush of hot air causes air to speed horizontally inward to the bottom of the newly-forming vortex. This rapidly rising pocket of air may begin to rotate, and if it continues to be stretched in the vertical direction, will increase in rotation speed. This increase in rotation speed from vertical stretching is similar to the increased spinning of an ice skater as they bring their arms in toward their bodies. As more hot air rushes in toward the developing vortex to replace the air that is rising, this spinning effect is intensified. As the air rises, it cools and eventually will descend back through the center of the vortex. Under optimal conditions, a balance between the hot air rising along the outer wall of the vortex and the cooler air sinking in the vortex occurs. The dust devil then begins to move across the ground, picking up more and more dust, which highlights the vortex making it visible to the eye. The dust devil, once formed, is a funnel-like chimney through which hot air moves both upward and circularly.

Answer 4

During hot days the warm ground does the updraft thingy and it spins upwards towards the sky. Though it isn't nearly as strong as a tornado they are really fun to get into the middle of. That is basically how it works like a small updraft of warm air.

Answer 5

Nothing causes a dust devil.It just appears out of nowhere for a hot day where one part of the ground the hotter than the rest

Answer 6

Thermals transport heat in the air, but they can be transient. If their effect suddently drops, a downrush of air can occur, and it can create its own circulation, becoming a dust devil. PS: I experienced one near Baltimore, MD which developed near gale-force winds and almost ruined a cultural fair. It was weird.

Answer 7

Mainly the result of human arrogance, greed, and stupidity. Check it out. Oh yeah, and check for the connections with the global depression which helped lead to WWII.

Answer 8

when your in the destert when there is lots of wind and sand the wind blows it