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Real-time integration of multi-parametric observations\ud is expected to accelerate the process toward improved, and\ud operationally more effective, systems for time-Dependent Assessment\ud of Seismic Hazard (t-DASH) and earthquake short-term (from\ud days to weeks) forecast. However, a very preliminary step in this\ud direction is the identification of those parameters (chemical, physical,\ud biological, etc.) whose anomalous variations can be, to some extent,\ud associated with the complex process of preparation for major earthquakes.\ud In this paper one of these parameters (the Earth’s emitted\ud radiation in the Thermal InfraRed spectral region) is considered for its\ud possible correlation with M C 4 earthquakes occurred in Greece in\ud between 2004 and 2013. The Robust Satellite Technique (RST) data\ud analysis approach and Robust Estimator of TIR Anomalies\ud (RETIRA) index were used to preliminarily define, and then to\ud identify, significant sequences of TIR anomalies (SSTAs) in 10 years\ud (2004–2013) of daily TIR images acquired by the Spinning Enhanced\ud Visible and Infrared Imager on board the Meteosat Second Generation\ud satellite. Taking into account the physical models proposed for\ud justifying the existence of a correlation among TIR anomalies and\ud earthquake occurrences, specific validation rules (in line with the\ud ones used by the Collaboratory for the Study of Earthquake Predictability—\ud CSEP—Project) have been defined to drive a\ud retrospective correlation analysis process. The analysis shows that\ud more than 93 % of all identified SSTAs occur in the prefixed space–\ud time window around (M C 4) earthquake’s time and location of\ud occurrence with a false positive rate smaller than 7 %. Molchan error\ud diagram analysis shows that such a correlation is far to be achievable\ud by chance notwithstanding the huge amount of missed events due to\ud frequent space/time data gaps produced by the presence of clouds\ud over the scene. Achieved results, and particularly the very low rate of\ud false positives registered on a so long testing period, seems already\ud sufficient (at least) to qualify TIR anomalies (identified by RST\ud approach and RETIRA index) among the parameters to be considered\ud in the framework of a multi-parametric approach to t-DASH

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Abstract.In the last few years, Robust Satellite data analysis Techniques (RST) have been proposed and successfully applied for monitoring major natural and environmental risks. Among the various fields of application, RST analysis has been used as a suitable tool for satellite TIR surveys in seismically active regions, devoted to detect and monitor thermal anomalies possibly related to earthquake occurrence. In this work, RST has been applied, for the first time, to thermal infrared observations collected by MODIS (Moderate Resolution Imaging Spectroradiometer) -the sensor onboard EOS (Earth Observing System) satellites -in the case of Abruzzo (Italy) earthquake occurred on 6 April 2009 (M L ∼5.8). First achievements, shown in this work, seem to confirm the sensitivity of the proposed approach in detecting perturbations of the Earths emission thermal field few days before the event. The reliability of such results, based on the analysis of 10 years of MODIS observations, seems to be supported by the results achieved analyzing the same area in similar observation conditions but in seismically unperturbed periods (no earthquakes with M L ≥5) that will be also presented.

Abstract.A self adaptive approach (RST, Robust Satellite Technique) has been proposed as a suitable tool for satellite TIR surveys in seismically active regions devoted to detect and monitor thermal anomalies possibly related to earthquake occurrence. In this work, RST approach has been applied to 15 years of AVHRR (Advanced Very High Resolution Radiometer) thermal infrared observations in order to study the 6 April 2009 Abruzzo earthquake. Preliminary results show clear differences in TIR anomalies occurrence during the periods used for validation (15 March-15 April 2009) and the one (15 March-15 April 2008) without earthquakes with M L ≥4.5, used for confutation purposes. Quite clear TIR anomalies appears also to mark main tectonic lineaments during the preparatory phases of others, low magnitude(3.9

In May 2016, three powerful paroxysmal events, mild Strombolian activity, and lava emissions took place at the summit crater area of Mt. Etna (Sicily, Italy). During, and immediately after the eruption, part of the North-East crater (NEC) collapsed, while extensive subsidence affected the Voragine crater (VOR). Since the end of the May eruptions, a diffuse fumarolic activity occurred from a fracture system that cuts the entire summit area. Starting from 7 August, a small vent (of ~20–30 m in diameter) opened up within the VOR crater, emitting high-temperature gases and producing volcanic glow which was visible at night. We investigated those volcanic phenomena from space, exploiting the information provided by the satellite-based system developed at the Institute of Methodologies for Environmental Analysis (IMAA), which monitors Italian volcanoes in near-real time by means of the RSTVOLC (Robust Satellite Techniques–volcanoes) algorithm. Results, achieved integrating Advanced Very High Resolution Radiometer (AVHRR) and Moderate Resolution Imaging Spectroradiometer (MODIS) observations, showed that, despite some issues (e.g., in some cases, clouds masking the underlying hot surfaces), RSTVOLC provided additional information regarding Mt. Etna activity. In particular, results indicated that the Strombolian eruption of 21 May lasted longer than reported by field observations or that a short-lived event occurred in the late afternoon of the same day. Moreover, the outcomes of this study showed that the intensity of fumarolic emissions changed before 7 August, as a possible preparatory phase of the hot degassing activity occurring at VOR. In particular, the radiant flux retrieved from MODIS data decreased from 30 MW on 4 July to an average value of about 7.5 MW in the following weeks, increasing up to 18 MW a few days before the opening of a new degassing vent. These outcomes, in accordance with information provided by Sentinel-2 MSI (Multispectral Instrument) and Landsat 8-OLI (Operational Land Imager) data, confirm that satellite observations may also contribute greatly to the monitoring of active volcanoes in areas where efficient traditional surveillance systems exist.