03-12-2014 Initial upload of the tephra2 probability scripts (perl scripts) which use the tephra2 model of ash dispersion to create survivor curves for specific locations around a volcano.
07-09-2013 Initial upload to GitHub. tephra2 is a tephra dispersion model based on an analytical (closed-form) solution of the advection-diffusion equation. This initial version uses a plume model based on the beta function and incorporates a 2-D wind model that varies in speed and direction with changes in elevation.