Assessment and improvement of a robust satellite technique (RST) for thermal monitoring of volcanoes

The RST approach (robust satellite technique) is a multi-temporal scheme of satellite data analysis already successfully used to monitor volcanoes at different geographic locations. In this work, the results of a long-term validation analysis of RST-based hot spot products are presented. This study was performed processing fourteen years of NOAA-AVHRR (National Oceanic and Atmospheric Administration-Advanced Very High Resolution Radiometer) records acquired over Mt. Etna area between 1 January 1995 and 31 December 2008, at different overpass times (day/night), and analyzing hundreds of volcano bulletins reporting information on Mt. Etna eruptive activity, provided by visual observations and ground-based measurements. An optimized configuration of the RST approach, named RSTVOLC, is also, for the first time, presented and discussed here. This method, thanks to a better tradeoff between reliability and sensitivity, may be particularly suitable to support operational systems for volcano monitoring and hazard mitigation.