Volcanoes activity Early warning system based on MSG SEVIRI data

Low-spectral, high-temporal resolution sensors on board geosynchronous satellites played an important role for monitoring known source of thermal anomalies. With the launch of the Meteosat Second Generation Spin Enhanced Visible and Infrared Imager (MSG-SEVIRI) it is now possible to follow with high-temporal resolution, changes of volcanoes summit thermal behaviour from space. This work is addressed to the analysis of volcanic area by means of thermal infrared data of Spinning Enhanced Visible and Infra-Red Imager (SEVIRI) onboard the geostationary satellite Meteosat Second Generation (MSG). In this paper the results obtained investigating datasets regarding the Mt Etna and Stromboli volcanoes both in the Sicily (South Italy) are presented. The Spinning Enhanced Visible and Infrared Imager sensor (SEVIRI) mounted on the Meteosat Second Generation (MSG) satellite produces 11 channels images every 15 minutes and the image processor, presented in this paper, provides radiance data with the same time rate. The system used is dedicated to the preprocessing, calibration, coregistration and storing of MSG-SEVIRI data. The MSG data processor collects different stripes of data coming from MSG SEVIRI and creates calibrated data files for the desired region. The overall architecture of the system has been home-developed in order to be used both for the continuous reception of data or to extract information from a single SEVIRI frame. This work emphasizes the capability of MSG-SEVIRI data for the estimation of parameter suitable for the volcanic monitoring. Measurements are made every 15 min, following the event evolution in near real time. The spectral radiance emitted by hot spots, reaches its maximum in the region of mid infrared (MIR, around 3 micron). Consequently, MSG 4th channel (centered at 3.9 micron), can be widely used for surface thermal monitoring, despite its relatively ground resolution cell (3 km nadir view). Investigating different data sets, regarding Mt Etna eruption (September 2004, July 2006, November 2006, November 2007) and Stromboli volcano eruption (February 2007), it has been pointed out that the beginning of new eruption is marked by a sudden increase of radiance value (up ten times) associated to the pixels centered over the crater (July 2006, November 2007, February 2007). The 3.9 micron MIR channel is saturated at 2.4 Watt/sr*m2*micron. The system proposed allows us to set up an early warning system dedicated to the impending eruption.