Abstract
Mt. Mihara at Oshima Island, about 100 km south to Tokyo erupted in the early evening, 21 November 1986. The authors, the Natural Disaster Survey Group, made a reception of the observation by NOAA Satellite 10 concerning the plume of eruption. Then we made airplane MSS observations of temperature patterns at ground surface in the island on the next day and 20 days later.
In this paper we present images processed by use of the above-stated observations. Regarding the eruption plume we obtained the following estimates from the images with the help of surface and radiosonde meteorological observations. The ejected plume went straight up to the altitudes from 3, 500m to 6, 000m. After that, it is concluded, the plume gradually ascended into the layer between some 7, 500m and 10, 000m height. This may agree with a JAL pilot reporting that the plume height was about 8, 000m.
