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The application of Structure-from-Motion (SfM) and Multi-View-Stereo matching with aerial images can be successfully used for deriving dense point clouds to analyse changes in the mountain environment, which is characterized by changes due to the action of natural process. The comparison of multiple datasets requires to setup a stable reference system, task that is generally implemented by means of ground control points (GCPs). On the other hand, their positioning may be sometimes difficult in mountains. To cope with this drawback an approach termed as Multitemporal SfM (MSfM) is presented: multiple blocks are oriented together within a unique SfM project, where GCPs are used in only one epoch for establishing the absolute datum. Accurate coregistration between different epochs depends on the automatic extraction of tie points in stable areas. To verify the application of MSfM in real cases, this paper presents three case studies where different types of photogrammetric data are adopted, including images from drones and manned aircrafts. Applications to glacier and mountain river erosion are entailed. [ABSTRACT FROM AUTHOR]

Since the mid-eighties, the space-time fluctuations of TIR radiation measured by satellite record have been considered as a possible earthquakes precursor (see Tramutoli et al., 2015). As proposed by several authors (Qiang et al., 1991; Tramutoli et al., 2001, 2013) the appearance of anomalously high TIR records near the place and the time of earthquake occurrence could be related to the increase of green-house gases (such as CO2, CH4, etc.) emission rates.Following the original idea of N. Bryant, Bleier et al. (2009) analyzing TIR (Thermal InfraRed) radiances measured by GOES-W satellite, report an apparent "nocturnal heating" in the area where Alum Rock earthquake occurred 13 days later (30 October 2007; M5.4). A similar effect was reported by Piroddi and Ranieri (2012) - using LST (Land Surface Temperature) products retrieved from MSG-SEVIRI radiances – few days before L'Aquila earthquake (6 April 2009; Mw 6.3).In this work, the multi-purpose change detection method named RST (Robust Satellite Technique; Tramutoli, 1998, 2005, 2007) has been used for studying "nocturnal heating" effect possibly associated to Amatrice earthquake (Mw 6.0) occurred 24 August 2016. To this purpose, TIR records collected by MSG/SEVIRI during nighttime (since 22:00 LT up to 04:50 LT) in the months of July and August from 2004 to 2016 over Italian peninsula have been used. Preliminary results shown TIR anomalies, identified by using the new RETIRSA (Robust Estimator of TIR-Slope Anomalies) index, starting from 2 days up to few hours before the main shock (24 August 2016; Mw 6.0). [ABSTRACT FROM AUTHOR]