Abstract
The Advanced Spaceborne Thermal Emission Reflectance Radiometer (ASTER) is a high resolution multispectral imager ideal for discerning physical variations on the active Soufrière Hills volcanic dome. Five band thermal infrared data at 90 meter spatial resolution can produce accurate temperature and emissivity data. These data can potentially provide information of glass and vesicle distribution across the changing dome, and therefore on internal processes. One cloud-free image is captured every three months on average, with increased frequency in 2002, where the volcano was a high priority target. Six nighttime ASTER scenes of the dome have been chosen based on coverage of the entire dome, the presence of thermal infrared anomalies, and pyroclastic flow activity, as well as a relative lack of cloud cover over the active dome. Montserrat Volcano Observatory (MVO) weekly reports from 1999 to present (available online) were also ingested into a multi-parameter, searchable database. These data, which detail specific volcanic activity, were compared against the ASTER data. The database fields include SO2 flux, high temporal resolution weather satellite-derived radiance measurements, description of dome growth and collapse, and intensities of pyroclastic flows, rockfalls, fumarolic activity, and seismic activity. This database provides a unique cross-reference for the interpretation of the spaceborne data, as well as highlighting observable trends in each of the volcanic activity types. Results from this study will provide a better understanding of the capabilities of the ASTER instrument to accurately describe active dome processes and to characterize these and other processes statistically. This knowledge can be applied to other active areas to study potential indicators of volcanic activity, dome collapse, the generation of hazardous pyroclastic activity, as well as the transition from effusive dome growth to explosivity.
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