Numerical Simulation of long-range atmospheric dispersion of SO_2 discharged from Miyake Island

摘要

The active volcano Oyama in the Miyake Island has been emitting a huge amount of volcanic gases since the first eruption in July 2000. High concentrations of SO_2 gas originated in Oyama frequently appeared in the wide area from the northeast to the west parts of Honshu, Japan. This paper describes the following simulations dealing with atmospheric dispersion of SO_2 from Miyake Island:(1) Retrospective simulation to find the mechanism of the transport of high concentration volcanic gas to the west Kanto District on 28 August, 2000 and to estimate the release amount of volcanic gas.(2) Retrospective simulation to find the mechanism of the transport of volcanic gas to Tokai and Kansai districts in a case of stench incident on 13 September, 2000.(3) Automated real-time simulation from the acquisition of meteorological data to the output of figures for operational predication of the transport of volcanic gas to Tokai and Kanto districts.