Laboratory experiments of forced plumes in a density-stratified crossflow and implications for volcanic plumes | INSTITUT DE PHYSIQUE DU GLOBE DE PARIS

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  Laboratory experiments of forced plumes in a density-stratified crossflow and implications for volcanic plumes

Publication Type:

Journal Article

Source:

Geophysical Research Letters, Volume 41, Number 24, p.8759-8766 (2014)

Abstract:

The mass eruption rate feeding a volcanic plume is commonly estimated from its maximum<br/>height. Winds are known to affect the column dynamics causing bending and hence reducing the<br/>maximum plume height for a given mass eruption rate. However, the quantitative predictions including<br/>wind effects on mass eruption rate estimates are not well constrained. To fill this gap, we present a series<br/>of new laboratory experiments on forced plumes rising in a density-stratified crossflow. We identify three<br/>dynamical regimes corresponding to increasing effect of wind on the plume rise. The transition from one<br/>regime to another is governed by two dimensionless velocity scales defined as a function of source and<br/>environmental parameters. The results are found consistent with the conditions of historical eruptions and<br/>provide new empirical relationships to estimate mass eruption rate from plume height in windy conditions,<br/>leading to valuable tools for eruption risk assessment.