Atmospheric dispersion simulations of volcanic gas from Miyake Island by SPEEDI

Japan Atomic Energy Research Institute is advancing the study for prediction of material circulation in the environment to cope with environmental pollution, based on SPEEDI (System for Prediction of Environmental Emergency Dose Information) and WSPEEDI (Worldwide version of SPEEDI), which are originally developed aiming at real-time prediction of atmospheric dispersion of radioactive substances accidentally released from nuclear facility. As a part of this study, dispersion simulation of volcanic gas erupted from Miyake Island is put into practice. After the stench incident at the west Kanto District on 28 August 2000 caused by volcanic gas from Miyake Island, the following simulations dealing with atmospheric dispersion of volcanic gas from Miyake Island have been carried out. (1) Retrospective simulation to analyze examine the mechanism of the transport of high concentration volcanic gas to the west Kanto District on 28 August and to estimate the release amount of volcanic gas. (2) Retrospective simulation to analyze the mechanism of the transport of volcanic gas to Tokai and Kansai districts in a case of stench incident on 13 September. (3) Automated real-time simulation from the acquisition of meteorological data to the output of figures for operational prediction of the transport of volcanic gas to Tokai and Kanto districts. This report describes the details of these studies. (author)