FUTUREVOLC Partner UNIVBRIS Jeremy Phillips, Mark Woodhouse, Andrew Hoggto develop and provide physics-based theoretical models of plume dynamics and tephra

dispersion to help understand the new observations/monitoring data and apply the results operationally

Deliverables (D7.1) Progress

Improved plume height-source mass flux relationships (MS60; 12 months);

• Plume height—source mass flux relationship including wind published (in JGR).

• Web-tool released to allow calculations to be made online.

• Testing of steady plume model with webcam images and volcanic lightning data (two papers in prep.).

Tephra deposition model based on an unsteady source and wind-affected plume (MS66; 18 months)

• Assessment of existing unsteady plume models.• On-going development of unsteady wind-blown

plume model.• Developed shallow-layer model of buoyancy-

driven intrusions with wind (JFM paper in prep.).• ‘Hybrid model’ of intrusions to allow rapid

calculations (paper in prep.).

Steady plume model1. Comparison with webcam

5 minute period – 60 images

data courtesy of Sonja Behnke (Uni. South Florida)

2. Comparison with lightning

3. Web-tool (www.plumerise.bris.ac.uk)

Unsteady plume models

Our analysis of a recent unsteady plume model (Scase & Hewitt 2012) shows an underlying pathology in the mathematical description.

Ongoing work is addressing this issue. The model will then be extended to volcanic plumes in a wind field in an attempt to describe unsteadiness in the source.

Buoyancy-driven intrusions

Wind & buoyancy are important for long-range tephra dispersal.

We’re developing a shallow-layer model of buoyancy-driven intrusions in a wind field. Model by Chris Johnson (Uni. Bristol)

Steady models not appropriate for eruptions with time varying source conditions.

Buoyancy forces are not usually considered in dispersion models.

Ongoing work to compare with observations and develop operational tools.