Satellite infrared analysis of active volcanoes

Abstract

Satellite remote sensing has been used for the analysis of active volcanoes since the mid 1980s when Landsat TM, a high spatial resolution sensor with wide spectral range, became available. Satellite remote sensing technique has advantages in spatial coverage, repeated observation capability, easy global access including remote areas and cost efficiency, compared with conventional ground-based methods. Infrared thermal analysis has been applied to investigation of various volcanic phenomena -degassing of the magma during lava dome growth, cooling and emplacement mechanism of lava flows, documentation of the detailed eruption processes and so on. Frequent time-series images from the metrological satellites have been utilised for investigating relationship between temporal variation of thermal anomalies and eruptive activities. These types of satellites also have been used for developing automated realtime monitoring systems by several institutes to monitor active volcanoes distributing wide areas. On the other hand, thermal infrared images from the hyperspectral satellites have been applied to estimation of SO₂ or existence of ash particles in eruption plumes. Next important issue to be explored in volcano remote sensing will be combined analysis among different types of remote sensing data or those and the ground-based observations.