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International audience; The main goal of the Ma_MISS instrument is to study the Martian sub-surface environment. Access to the Martian subsurface is crucial to constrain nature, timing and duration of alteration and sedimentation processes on Mars, as well as habitability conditions. Subsurface deposits likely host and preserve water ice and hydrated materials diagnostic for understanding the water geochemical environment (both in the liquid and solid state) at the landing site.

Nell'ambito di un lavoro di tesi in collaborazione tra il Dipartimento di Scienze della Terra dell' Università di Torino e il gruppo di ricerca GeoClimAlp del CNR-IRPI, è stata analizzata la correlazione tra instabilità dei versanti ed evoluzione della criosfera per un settore delle Grandes Murailles. Seguendo i criteri proposti per la "Carta delle litofacies in funzione dell'instabilità della Valle d'Aosta" (Progetti "IFFI "e "Risknat"), è stata realizzata una classificazione dello stato reologico del substrato roccioso, integrata dalla caratterizzazione geomorfologica dell'area. L'interpretazione si è basata su dati di terreno e riprese aeree. Servendosi di immagini storiche e ortofoto digitali è stata anche analizzata l'evoluzione degli ambienti glaciale e periglaciale dell'area. In particolare, oltre alla ricostruzione cronologica di alcuni eventi di frana, sono state mappate le variazioni dell'estensione del Ghiacciaio di Mont Tabel a partire dalla Piccola Età Glaciale (1850 circa) e più dettagliatamente fra il 1954 e il 2012. Dalla Alpine Permafrost Index Map (Boeckli et al., 2012) è stata infine ricavata la probabilità di occorrenza di permafrost nell'area indagata. La correlazione tra le caratteristiche geologico-geomorfologiche del versante e l'evoluzione della criosfera ha permesso la formulazione di ipotesi sull'evoluzione futura del paesaggio geomorfologico nel contesto dei cambiamenti climatici in atto.

Description of SeaBIRD (Searchable and Browsable Infrastructure for Repository of Data), a software and hardware infrastructure for multi-mission planetary datamining, with web-based GUI and API set for the integration in users' software.

Rock glaciers are slowly flowing mixtures of debris and ice occurring in mountains. They can represent a reservoir of water, and melting ice inside them can affect surface water hydrochemistry. Investigating the interactions between rock glaciers and water bodies is therefore necessary to better understand these mechanisms. With this goal, we elucidate the hydrology and structural setting of a rock glacier-marginal pond system, providing new insights into the mechanisms linking active rock glaciers and impounded surface waters. This was achieved through the integration of waterborne geophysical techniques (ground penetrating radar, electrical resistivity tomography and self-potentials) and heat tracing. Results of these surveys showed that rock glacier advance has progressively filled the valley depression where the pond is located, creating a dam that could have modified the level of impounded water. A sub-surface hydrological window connecting the rock glacier to the pond was also detected, where an inflow of cold and mineralised underground waters from the rock glacier was observed. Here, greater water contribution from the rock glacier occurred following intense precipitation events during the ice-free season, with concomitant increasing electrical conductivity values. The outflowing dynamic of the pond is dominated by a sub-surface seepage where a minor fault zone in bedrock was found, characterised by altered and highly-fractured rocks. The applied approach is evaluated here as a suitable technique for investigating logistically-complex hydrological settings which could be possibly transferred to wider scales of investigation. Copyright © 2017 John Wiley & Sons, Ltd.

International audience; MATISSE is a web tool allowing 3D visualization of planetary data. Here we discuss the new functions implemented on MATISSE to allow visualization of derived and high-level data, as well as the implementation of protocols to make it compatible with the planetary Virtual Observatory, developed under the VESPA-Europlanet2020 activity.

International audience

Aims. We present a study of the spectrophotometric properties of dwarf planet Ceres in the visual-to-infrared (VIS-IR) spectral range by means of hyper-spectral images acquired by the VIR imaging spectrometer on board the NASA Dawn mission. Methods. Disk-resolved observations with a phase angle within the 7 ◦ < α < 132 ◦ interval were used to characterize Ceres’ phase curve in the 0.465-4.05 µm spectral range. Hapke’s model was applied to perform the photometric correction of the dataset to standard observation geometry at VIS-IR wavelength, allowing us to produce albedo and color maps of the surface. The V-band magnitude phase function of Ceres as been computed from disk-resolved images and fitted with both the classical linear model and H-G formalism. Results. The single- scattering albedo and the asymmetry parameter at 0.55 µm are w = 0.14±0.02 and ξ = −0.11±0.08, respectively (two-lobe Henyey-Greenstein phase function); at the same wavelength, Ceres’ geometric albedo as derived from our modeling is 0.094±0.007; the roughness parameter is ¯ θ = 29 ◦ ±6 ◦ . Albedo maps indicate small variability on a global scale with an average reflectance at standard geometry of 0.034 ± 0.003. Nonetheless, isolated areas such as the Occator bright spots, Haulani, and Oxo show an albedo much higher than average. We measure a significant spectral phase reddening, and the average spectral slope of Ceres’ surface after photometric correction is 1.1%kÅ −1 and 0.85%kÅ −1 at VIS and IR wavelengths, respectively. Broadband color indices are V−R = 0.38±0.01 and R−I = 0.33±0.02. Color maps show that the brightest features typically exhibit smaller slopes. The H-G modeling of the V-band magnitude phase curve for α < 30 ◦ gives H = 3.14±0.04 and G = 0.10±0.04, while the classical linear model provides V(1,1,0 ◦ ) = 3.48±0.03 and β = 0.036±0.002. The comparison of our results with spectrophotometric properties of other minor bodies indicates that Ceres has a less back-scattering phase function and a slightly higher albedo than comets and C-type objects. However, the latter represents the closest match in the usual asteroid taxonomy.

The evolution of the Mont Tabel Glacier over the last 150 years

L'itinerario del Miage e della Val Veny si sviluppa al cospetto del Monte Bianco ed è composto da tre percorsi collegati tra loro, i quali offrono nelle Soste alcune visioni panoramiche d'insieme e numerosi approfondimenti locali di dettaglio sui ghiacciai del Miage, della Brenva, della Lex Blanche e sugli altri apparati minori. In particolare è possibile fare alcune osservazioni in merito alIe pulsazioni tardoglaciali, oloceniche e storiche, all'instabilità delle pareti rocciose e delle morene, alla copertura detritica del Miage e alla sua articolata morfologia, alla presenza della vegetazione arborea sulla sua superficie, e all'evoluzione del Lago del Miage.

The analysis of glacial and periglacial morphodynamics and the study of past climate changes are important tasks for scientific and management purposes within recently deglaciated areas. Climate changes and related effects occurring in the last decades cause uncertainties on the survival of glaciers and affect stability of mountains. A systematic study of natural hazards related to glacial and periglacial morphodynamics of the Western Alps in Italy and the Coast Mountain and the Cordillera in Canada started only in the early 1990s. Since then, several instability phenomena of these glacial and periglacial environments have been analyzed, as well as their relationship with the climatic and environmental changes taking place since the end of the Little Ice Age. From the beginning of the 2000s, it became clear that environmental changes related to global warming were accelerating so quickly in high elevation and glaciated mountains. Within this perspective, we started an international effort to collect data and compare geomorphic processes occurring in the high mountains of two distant geographic areas, but with similar physiographic characteristics. Aims was to provide scientists and local administrations with the most advanced knowledge and tools to deal with climate-related instability events occurred in glacial and periglacial areas of the Italian Alps and of Western Canada, such as landslides, debris flows, glacial lake outburst floods, ice avalanches. We identified the types of instability mainly conditioned by climate change and discussed hazard scenarios. Methodological approaches used in Italy and Canada for studying the impacts of degrading permafrost and glacier ice loss on mountain environments were compared, and strategies for communication and dissemination of results were addressed. Studies have shown differences and similarities among the two areas, which highlight the effects of regional/local physiography and climate and, at the same time, confirm the global scale of the changes underway.

A systematic study of glacier-related hazards in the Western Alps started in Italy only in the early 1990s, and greatly benefited from the pioneering studies of John Clague. He analyzed natural instability processes in the glaciated environment and their relationship with the climatic and environmental changes taking place since the end of the Little Ice Age. From the beginning of the 2000s, it became clear that environmental changes related to global warming were accelerating so quickly in high elevation and glaciated mountains. An international effort to collect and exchange data was thus required, in order to provide scientists and local administrations with the most advanced knowledge and tools to deal with the impacts of climate change. This was the premise behind the start of a fruitful scientific collaboration developed over nearly 10 years between the authors and John Clague and other Canadian scientists, with the aim to compare geomorphic processes occurring in the high mountains of two distant geographic areas, but with similar physiographic characteristics. In this framework, we analyzed and compared instability events occurred in glacial and periglacial areas of the Italian Alps and of Western Canada, such as landslides, debris flows, glacial lake outburst floods, ice avalanches. We identified the types of instability mainly conditioned by climate change and discussed hazard scenarios. Methodological approaches used in Italy and Canada for studying the impacts of degrading permafrost and glacier ice loss on mountain environments were compared, and strategies for communication and dissemination of results were addressed. Studies have shown differences and similarities among the two areas, which highlight the effects of regional/local physiography and climate and, at the same time, confirm the global scale of the changes underway. These fruitful research results fed educational activities and research training within international academic exchange programs such as GeoNatHaz.