ou então ver a definição do Grande dicionário terminológico do Québec - Canadá
"Rising, columnar current of hot but solid material which might well up from below the asthenosphere, at a phase-change boundary a few hundred miles inside the mantle."

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Note added at 14 minutes (2008-09-17 07:59:28 GMT)
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diria "Coluna de gás"

Opção


- Plume: A visible or measurable discharge of a contaminant from a given point of origin that can be measured according to the Ringelmann scale. (Glossary of Air Pollution Terms)

- Plume
A volume of a substance that moves from its source to places farther away from the source. Plumes can be described by the volume of air or water they occupy and the direction they move. For example, a plume can be a column of smoke from a chimney or a substance moving with groundwater.

- A "plume" in the DIRSIG(Digital Imaging and Remote Sensing Laboratory ) context is a release of gas into the atmosphere from a point source. For DIRSIG to successfully render the plume, as with all materials in the scene, the optical properties of the gas must be known. Physical properties such as gas density and temperature are also required. Full treatment of the transmission through and emission by the plume are incorporated and described below. Currently, DIRSIG does not support any scattering effects in the plume. Consequently, plumes with large water-droplet concentration, such as those from cooling tower stacks, are not able to be simulated within DIRSIG. This feature will be implemented in future versions of DIRSIG. dirsig.cis.rit.edu/docs/manual/plumemodeling.html - 7k

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uma alternativa seria coluna de gás, mas acho preferível núvem

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Note added at 1 hr (2008-09-17 09:12:00 GMT)
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nuvem sen acento, claro

ou fomos gasosos, que eu não gosto muito