Development of a Prediction Scheme for Volcanic Ash Fall from Redoubt Volcano, Alaska

The purpose of this project is to develop a volcanic plume prediction model for volcanoes located in the Cook Inlet area, Alaska. Knowing where the ash plume is and predicting where it will go are important for public health and safety, as well as for flight operations and mitigating economic damage. For near-real-time plume prediction, acquisition of upper-air wind data is the essential part of the prediction scheme. In this project, near-real-time meteorological data are provided by the National Meteorological Center, transmitted via Unidata. Reading the real-time and forecast wind data, the prediction model computes advection, diffusion, and gravitational fallout for the plume particles from the vertical column over the volcano. Three-dimensional dispersal of plume particles are displayed on the computerized graphic display as a h c t i o n of time following the eruption. The model predictions appear on the screen about 15 minutes after the eruption report, showing the geographical distributions of plume dispersal for the following several hours. Although the model simulation inevitably has forecast errors owing largely to errors in the forecast wind input, the prediction product offers a useful guide for public safety, especially for the Cook Inlet area, Alaska.