The dynamics of mantle flow and melting of a ridge-centered plume were investigated with three-dimensional variable-viscosity numerical models, focusing on three buoyancy sources: temperature, melt depletion, and melt retention. The width, W, to which a plume spreads along a ridge axis, depends on plume volume flux, Q, full spreading rate, U, buoyancy number, B, and ambientrplume viscosity cont...

A simple model for laser ablation plasma plume expansion in a background gas is presented. The expanding plume is approximated by a semi-ellipsoidal shell of infinitesimal thickness and with a mass corresponding to the amount of background gas that has been snowploughed by the shell as it expands. Furthermore, the internal pressure of the plume and external pressure of the background gas are ta...

Water mass modification in surface-trapped, near-field river plumes is examined using a 1.5-layer reduced gravity model and a three-dimensional numerical model. Solutions to the layermodel are shown to be qualitatively similar to previous observations and three-dimensional simulations of near-field plumes. Analytic analysis of the layer model demonstrates how the near-field plume is controlledb...

Observations of volcanic lightning made using a lightning mapping array during the 2010 eruption of Eyjafjallajökull allow the trajectory and growth of the volcanic plume to be determined. The lightning observations are compared with predictions of an integral model of volcanic plumes that includes descriptions of the interaction with wind and the effects of moisture. We show that the trajector...

Observations of volcanic lightning made using a lightning mapping array during the 2010 eruption of Eyjafjallajökull allow the trajectory and growth of the volcanic plume to be determined. The lightning observations are compared with predictions of an integral model of volcanic plumes that includes descriptions of the interaction with wind and the effects of moisture. We show that the trajector...

River plume fronts off NW Iberia during autumn 2002 are examined based on the gradient of the mixed layer depth (MLD) in threedimensional model data and on sea surface temperature gradients in Advanced Very High Resolution Radiometer (AVHRR) imagery. The method reveals new aspects of the dynamics of fronts in the area. The strong gradient of the MLD between the plume and the adjacent ocean serv...

United States Environmental Protection Agency (USEPA) set opacity standards for visual emissions from industrial sources to protect ambient air quality. USEPA developed Method 9, which is a reference method to describe how plume opacity can be quantified by human observers during daytime conditions. However, it would be beneficial to determine plume opacity with digital still cameras (DSCs) to ...

We present Daysmoke, an empirical-statistical plume rise and dispersion model for simulating smoke from prescribed burns. Prescribed fires are characterized by complex plume structure including multiple-core updrafts which makes modeling with simple plume models difficult. Daysmoke accounts for plume structure in a three-dimensional veering/sheering atmospheric environment, multiple-core updraf...

The writers present a one-dimensional integral model to describe multiphase plumes discharged to quiescent stratified receiving waters. The model includes an empirical submodel for detrainment, and the capability to include dispersed phase dissolution. Model equations are formulated by conservation of mass, momentum, heat, dissolved species concentration, and salinity, and allow the tracking of...

The structure of a river plume is related to the vertical mixing using an isohaline-based coordinate system. Salinity coordinates offer the advantage of translating with the plume as it moves or expanding as the plume grows. This coordinate system is used to compare the relative importance of different dynamical processes acting within the plume and to describe the effect each process has on th...