Investigating the temporal fluctuations in satellite advanced very high resolution radiometer thermal signals measured in the volcanic area of Etna

The time dynamics of long-term time series of satellite thermal signal, measured at Mount Etna, has been investigated. The signal has been analyzed by means of a recently proposed multi-temporal and robust technique (RST), which has already shown to be better capable to detect and monitor vol- canic hotspots, compared to traditional satellite approaches. The temporal fluctuations of the thermal signal detected by RST over a long series (1995-2005) of Advanced Very High Resolution Radiome- ter (AVHRR) satellite data, have been characterized by means of the correlation function and the power spectrum analysis, which have shown the presence of correlation structures in the thermal time series recorded in the crater area.