by Angelina Moore

Created on: March 05, 2009   Last Updated: March 06, 2009

Whirlwinds, dancing dervishes, willy-willy, whirly whirly; dust devils have many different names across the world.

A dust-devil is a strong, powerful, long-lived tumultuous cyclone. They are very rare however when they strike; although some can be harmless; some can strike with immense power and inflict severe harm to people and their property. They range from many sizes including over 10 meters wide to over 1000 meters tall; this is the largest type of dust devil that has been recorded. A small dust devil ranges from half a meter wide and a few meters tall, these types of dust devils would not cause much harm onto anybody or anything.

How Dust devils form

When hot air collides near the surface of the ground and rises rapidly upwards into a low pressure that lies above, a dust devil is formed. With the right conditions applied, the air then begins to rotate intently. As the air continues to rise with great speed it is pulled upwards causing the spinning effect of the two air pressures to become even more colossal and immense ; the spinning rotates at a much faster rate.

With the spinning motion rotating faster the dust devil causes more hot air to form which is made to flow horizontally at a hasty pace to the bottom of the newly forming whirlpool. As more hot air tears inwards to the emerging whirlpool it substitutes the air that is escalating upwards. This results in the spinning rotation becoming yet more powerful and vigorous, which starts to cause concern for destruction of people and their assets.

Dust devils are very similar to tornadoes by the shape that they form, as they begin to become in full flow. It outlines a funnel-chimney like shape as the hot air soars off the ground as well as in the centre of the whirlpool.

Although the hot air continually rises it meets the cooler air and as a result of this the air starts to cool down. This causes the air to lose its resilience and optimism to carry on its journey of demolition and eventually stops rising. As the cool air returns its balances the hot air that is placed on the outside wall of the dust devil. This acts as a way of calming down the dust devil to reduce its speed.

However this process is affected by the environmental conditions surrounding the dust devil. For example; the hotter the surface the longer the spinning effect is able to maintain itself, for a longer period of time. The surface friction that is caused by the spinning motion continues the forward momentum as well.

The dust devil tries to

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