Glaciated and recently (post-Little Ice Age) deglaciated areas are very dynamic environments, undergoing continuous changes, in particular as a consequence of climatic fluctuations and cryosphere ...changes. The intense geomorphic activity that takes place here conditions natural hazard, sediment transport and tourist fruition. A geo-morphological mapping with applicative purposes has to take into account the peculiarities and the dynamism of these specific areas. We here propose a methodological approach based on the interpretation of a multitemporal set of aerial photos (from 1983 to 2012), in a GIS environment, with application to the sectors modeled by Little Ice Age glaciers in the upper Orco Valley (NW Italy). The result is a geo-morphological map focused on the elements that are most relevant for application purposes, complemented by a map of the spatio-temporal distribution of the natural instability processes identified in the study area for the reference period, aimed to highlight the recent dynamism of the geomorphological elements in the map.
Like any science, geology has a key role in the development and progress of human culture and society. In this context, scientists, professionals and practitioners of Earth sciences must inevitably ...confront themselves with the purposes, methods and results of their studies, concerning relationships between man and his environment, which thus deals with ethical questions. An essential base for any geo-environmental action should be respect for the natural ecosystem. This can be achieved by encouraging an ‘affectionate attitude’ towards Nature or ecology. Some ancient cultures had a great awareness of the close relationships between humankind and the Earth. The recent web-based ‘Museo Torino’ (Turin Museum) multimedia product shows the ‘history of a city’ (Turin, Italy) in a dimension of unity and as a continuum of space–time–life between the history of the Earth and of humans. Geoscientists are not limited to merely having a pragmatic vision of the Earth, but should pursue harmonious collaboration between man and Nature. Within complex Earth systems, scientists and professionals rediscover their geoethical roles by responsibly evaluating and managing georesources, for progress aimed at improving conditions of life and human dignity. Geoscientists can also promote respect for ‘human rights’ through appropriate educational and training actions, for the balanced exploitation of our georesources. An example from Mendoza (Argentina) is presented here, to encourage opportunities for meetings on environmental issues among people of different backgrounds and cultures. Last, but not least, there is the ethical role of geoscientists in ‘the service of the truth’. A misleading view of Earth systems by geoscientists can lead to fatalism or myths that often affect people from the psychological and sociological points of view.
In this work, we analyze climate variability and glacier evolution for a study area in the Northwestern Italian Alps from the Little Ice Age (LIA) to the 2010s. In this area, glacier retreat has been ...almost continuous since the end of the LIA, and many glaciers are now extinct. We compared glaciological and climatic data in order to evaluate the sensitivity of glaciers to temperature and precipitation trends. We found that temperatures show significant warming trends, while precipitation shows no clear signal. After the 1980s, the total number of positive trends in temperature increased, particularly minimum temperature. The latter does not seem to be the only cause of glacier shrinkage but rather on acceleration of an ongoing trend documented since the end of the LIA. In some rare cases, the effects of warming trends on glacier dynamics have been accentuated by a concomitant decrease in precipitation. We hope that this study will contribute to increase the knowledge of the relationships between climate variation and glacier evolution in the Greater Alpine Region.
A detailed geological survey of the Southern slope of Turin Hill reveals a Pleistocene terraced fluvial succession consisting of flat surfaces separated by scarps with associated fluvial clayey-silty ...and gravelly sediments. This succession is not linked to the present N-S hilly streams, but is instead related to major Pleistocene W-E rivers. The collected regional data suggest an ancient trend of the Po River flowing across Turin Hill, prior to its present course to the north of the hill. The Pleistocene terraced fluvial succession of the Western slope of Turin Hill is also mapped, based on a previous survey to allow a full reconstruction of the ancient rivers. The collected regional data and the petrographic analysis show that this succession is related to an ancient tributary of the Po River (Dora Riparia River). Wide saddles of the same river have been mapped on the main watershed between the two slopes of Turin Hill. The capping of soils less evolved with decreasing elevation over the fluvial sediments and landforms indicates that the whole terraced succession covers a large time range (Middle-Upper Pleistocene). The reported geologic successions and the current morphology of the relief result from the uplift and deformation of the Pleistocene Po Plain and the Dora Riparia Plain that were shaped at the south of Turin Hill. The proposed age/elevation relationships for the mapped terraces suggest a remarkable uplift of Turin Hill during the late Quaternary.
Glaciers are widely recognized as the best terrestrial indicators of climate change. Nevertheless, changes that have occurred since the end of the Little Ice Age (LIA) are often poorly understood. In ...Italy, glacier front variations in the last 100 years have been well documented, thanks to the efforts of the Italian Glaciological Committee (Comitato Glaciologico Italiano, CGI), which coordinates annual surveys on all glaciers, since 1927, in order to measure their front positions. However, although front variations are the easiest measurements to take in the field, they only partially describe changes that occur on the entire glacial mass. Moreover, the last national glacier inventory dates back to 1957-1958, which was promoted by the CGI on the occasion of the International Geophysical Year. Authors of the present work herein provide an updated inventory of present-day (2006) glaciers in the Western and South-Western Piedmont Alps (situated in the provinces of Turin and Cuneo). Along with the present-day glacial outlines, the map also includes a reconstruction of the extent of the glaciers during the Little Ice Age, inferred from morphological features such as LIA and post-LIA moraine ridges as well as the aid of historical archive data. Some basic glacier morphometric parameters (surface, length, width, mean slope, highest and lowest altitude, exposure) were computed for the two specified time periods (LIA and 2006). This study was carried out under the framework of the project 'GlaRiskAlp - Glacial Risks in Western Alps', project n.° 56 under the 2007-2013 ALCoTra programs.
ABSTRACT
Our new dataset from the Rivoli‐Avigliana end‐moraine system, the westernmost amphitheatre of the Italian Alps, provides an important step towards understanding foreland‐reaching glaciations ...before and during the Last Glacial Maximum (LGM) in the Western Alps. 10Be data from six boulders in pre‐LGM deposits gave ages between 26.8 ± 2.1 and 41.2 ± 1.9 ka. Based on morphological and pedological data, we interpret the oldest age as a minimum age for the glacier advance(s). 10Be results suggest that the LGM occurred in two major steps. During the first at 24.0 ± 1.5 ka, several ridges were constructed demonstrating oscillation of the Dora Riparia glacier snout at the maximum position. Our data demonstrate a significantly larger LGM extent in the Rivoli‐Avigliana amphitheatre than shown on previous maps. The maximum advance was followed by a short re‐advance of the glacier at 19.6 ± 0.9 ka, as recorded by 10Be ages from boulders in lateral positions along the lower Susa Valley. The maximum ice surface during the LGM was at 1000–920 m a.s.l. in the final reach of the valley (560–620 m of elevation above the alluvial plain) and at 620–340 m a.s.l. at the continuous moraines in the amphitheatre.
Detailed analysis of Digital Terrain Models (DTMs), digital imagery, and a discussion of their various applications and derived geothematic products are presented for study areas in two different ...geological and geomorphological contexts of North West (NW) of Italy. In both cases it has been proposed an integrated approach for geomorphological analysis that put in evidence many advantages of using these new geomatics tools.
In the first context, digital geomorphological mapping of high altitude areas of the Aosta Valley (Gran Paradiso and Gran San Bernardo) have been carried out by using photogrammetry and remote sensing on airborne laser scanner data (LiDAR derived DTM) and orthophotos. Suitable results have been obtained for areas of difficult accessibility, with reduced costs and work time compared to traditional field techniques.
In the second geomorphological context, high-resolution images of the present topography of the high Piedmont plain (Turin, Asti and Cuneo Provinces) have been used to perform GIS mapping and analysis. Evidences of Quaternary modifications in the hydrographic network have been enhanced, suggesting new geomorphological elements for the reconstruction of the recent geodynamic history of the area.
Nello stop lungo l'incisione della Dora Riparia nel tratto compreso tra gli abitati di Alpignano e Collegno, sono visibili i più antichi termini della successione quaternaria affiorante nell'area ...dell'AMRA. Si tratta dei depositi fluviali dell'unità di S. Gillio sui quali appoggiano i depositi glaciali di fondo dell'Allomembro di C.ne Vica.
Nello stop lungo l'incisione della Dora Riparia nel tratto compreso tra gli abitati di Alpignano e Collegno, sono visibili i più antichi termini della successione quaternaria affiorante nell'area ...dell'AMRA. Si tratta dei depositi fluviali dell'unità di S. Gillio sui quali appoggiano i depositi glaciali di fondo dell'Allomembro di C.ne Vica.
Carraro Francesco, Fioraso Gian Franco, Lucchesi Stefania. Arrêt 2 -Sols fossiles et surfaces de base des unités glaciaires de l'amphithéâtre morainique de Rivoli - Avigliana (Pianezza) . In: Collection EDYTEM. Cahiers de géographie, numéro 3, 2005. Le quaternaire des vallées alpines. Fronts glaciaires, mouvements de versants et comblements dans les vallées de l'Arve, d'Aoste et de Suse. Livret-guide de l'excursion organisée par l'AFEQ du 2 au 4 juin 2005. pp. 158-159.
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