Difference between revisions of "Dust devil"

From Glossary of Meteorology
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<div class="definition"><div class="short_definition">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.</div><br/> <div class="paragraph">Dust devils are occasionally strong enough to cause minor damage (up to EF0 on the [[Enhanced Fujita scale|Enhanced Fujita scale]]). Diameters [[range]] from about 3 m to greater than 30 m; their average height is about 200  m, but a few have been observed as high as 1 km or more. They have been observed to rotate  anticyclonically as well as cyclonically. Although the [[vertical velocity]] is predominantly upward,  the flow along the axis of large dust devils may be downward. Large dust devils may also contain  secondary vortices. Dust devils are best developed on a hot, [[calm]] afternoon with [[clear]] skies, in  a dry region when intense surface heating causes a very steep [[lapse rate]] of [[temperature]] in the  lowest 100 m of the [[atmosphere]].</div><br/> </div>
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<div class="definition"><div class="short_definition">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.</div><br/> <div class="paragraph">Dust devils are occasionally strong enough to cause minor damage (up to EF0 on the [[Enhanced Fujita scale|Enhanced Fujita Scale]]). Diameters [[range]] from about 3 m to greater than 30 m; their average height is about 200  m, but a few have been observed as high as 1 km or more. They have been observed to rotate  anticyclonically as well as cyclonically. Although the [[vertical velocity]] is predominantly upward,  the flow along the axis of large dust devils may be downward. Large dust devils may also contain  secondary vortices. Dust devils are best developed on a hot, [[calm]] afternoon with [[clear]] skies, in  a dry region when intense surface heating causes a very steep [[lapse rate]] of [[temperature]] in the  lowest 100 m of the [[atmosphere]].</div><br/> </div>
 
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Revision as of 11:29, 28 April 2016



dust devil

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.

Dust devils are occasionally strong enough to cause minor damage (up to EF0 on the Enhanced Fujita Scale). Diameters range from about 3 m to greater than 30 m; their average height is about 200 m, but a few have been observed as high as 1 km or more. They have been observed to rotate anticyclonically as well as cyclonically. Although the vertical velocity is predominantly upward, the flow along the axis of large dust devils may be downward. Large dust devils may also contain secondary vortices. Dust devils are best developed on a hot, calm afternoon with clear skies, in a dry region when intense surface heating causes a very steep lapse rate of temperature in the lowest 100 m of the atmosphere.