Aldino Bondesan

Current Behaviour and Dynamics of the Lowermost Italian Glacier (Montasio Occidentale, Julian Alps)

Abstract Smaller glaciers (<0.5 km2) react quickly to environmental changes and typically show a large scatter in their individual response. Accounting for these ice bodies is essential for assessing regional glacier change, given their high number and contribution to the total loss of glacier area in mountain regions. However, studying small glaciers using traditional techniques may be difficult or not feasible, and assessing their current activity and dynamics may be problematic. In this paper, we present an integrated approach for characterizing the current behaviour of a small, avalanche‐fed glacier at low altitude in the talian lps, combining geomorphological, geophysical and high‐resolution geodetic surveying with a terrestrial laser scanner. The glacier is still active and shows a detectable mass transfer from the accumulation area to the lower ablation area, which is covered by a thick debris mantle. The glacier owes its existence to the local topo‐climatic conditions, ensured by high rock walls which enhance accumulation by delivering avalanche snow and reduce ablation by providing topographic shading and regulating the debris budget of the glacier catchment. In the last several years the glacier has displayed peculiar behaviour compared with most glaciers of the uropean lps, being close to equilibrium conditions in spite of warm ablation seasons. Proportionally small relative changes have also occurred since the Little Ice Age maximum. Compared with the majority of other Alpine glaciers, we infer for this glacier a lower sensitivity to air temperature and a higher sensitivity to precipitation, associated with important feedback from increasing debris cover during unfavourable periods.

Geomorphological evolution of the plain between the Livenza and Piave Rivers in the sixteenth and seventeenth centuries inferred by historical maps analysis (Mainland of Venice, Northeastern Italy)

The ancient hydrographical network and geomorphological framework of the fluvial and coastal plain encompassed between the Livenza and Piave Rivers in the mainland of Venice (Northeastern Italy) were reconstructed, based on historical maps, georeferenced, and overlaid on available geomorphological maps and aerial photographs. A selection of 59 maps was accurately analyzed (32 from the sixteenth century, 31 from the seventeenth century, and 6 from the eighteenth century). They were selected by author, commitment, date, and scale, from among more than 1000 maps edited by Savi e Esecutori alle Acque (the ‘hydrographical’ service during the Republic of Venice) in the 16th and seventeenth century. The most representatives (7 from the sixteenth century and 6 from the seventeenth century) were georeferenced and redrawn. Finally, four 1:50.000 maps were created, picturing the ancient morphology and hydrographical network in the years 1550, 1600, 1650, and 1700, covering an area of about 130 square kilometers. Geographical information was compared with historical documents and geological, geomorphological, and geochronological data. Further comparison of geodetic maps from the eighteenth to the twenty-first century produced new maps with important information on the paleogeographical and environmental framework across two centuries, and particularly on the artificial diversion projects performed by the Venetian Republic, their effectiveness, and the geomorphological changes both related to human intervention and recent climatic changes.

Geomorphological Processes and Landscape Evolution of the Lagoon of Venice

The Lagoon of Venice, extending along the northern Adriatic coast in northeastern Italy, is the most important Italian lagoon. The delta systems of the Po, Adige and Brenta rivers delineate the lagoon from the south, whilst the Sile and Piave rivers border the lagoon in the north. The lagoon is closed by the barrier islands of Lido and Pellestrina and the spit of Cavallino. Inside the lagoon, several landforms typical of this peculiar environment are present: islands, salt marshes, tidal flats, fluvial deltas, tidal channels, sand dunes, ancient coastlines and man-made forms such as landfills, fish farms, coastal defences and artificial channels. Due to protracted human interference with natural processes, the Lagoon of Venice may be considered today as an artificial environment.

Geophysical Imaging of the WWI Archeological Site of Linke Peak (Forni Glacier, Italian Central Alps)

The centenary of World War I triggered several and relevant studies in the fields of Conflict Archeology. The research scenario becomes even more challenging when the study site is located at high altitude in the Alps were past battles and also the modern research should face extreme conditions. A major research project was recently undertaken in the saddle between Mount Vioz and the Linke peak, in the Cevedale massif, where the progressive retreat of the Forni and of the Vedretta Rossa glaciers exposed barracks, tunnels, barbed wire, sledges, ammunitions and several other war remains. Geophysical imaging was the core of the project that was focused on a double objective: mapping possible WWI remains embedded in the ice and a obtaining some information on the glacier. Results from two different geophysical campaigns were encouraging as radar and seismic profiling provided detailed data about geometry and properties of the glacier as well as unexpected evidences of buried structures.

GPR and seismic surveying in the World War I scenario of Punta Linke (Ortles-Cevedale Group, Italian Alps).

The Ortles-Cevedale Group was the setting of repeated clashes occurring under extreme conditions and at the highest altitudes of all fightings in the Great War (WWI). The research scenario associated with the group is very challenging because modern research faces a series of logistical and climatic obstacles. The gradual retreat of glaciers has unearthed several archaeological remains of WWI such as barracks, barbed wire, military ammunition, weapons and other materials. The study site is the saddle between M. Vioz and Punta Linke, where the Historic War Museum of Pejo, under the direction of the Archaeological Service of the Province of Trento (Soprintendenza per i Beni Culturali, Ufficio Beni Archeologici), started an archaeological excavation in the year 2009 of some of the infrastructure of the cableway station, which also includes a tunnel section in the bedrock. The saddle is placed at the head of Forni Glacier. GPR and seismic imaging was the best survey choice to characterize the glaciological and geo-archaeological context and to find structures or remains within the ice mass. Geophysical imaging spanned two campaigns in the years 2010 and 2011. The ice-rock interface was reconstructed in detail to depths greater than 45-50 m. The surface of the bedrock reveals a complex morphology, with several undulations and two rocky ridges elongated in the NNW-SSE direction. They identified some anomalous reflectors within the ice mass located near the western edge of the saddle of Punta Linke. The interpretation of radar profiles seems to indicate the presence of a tunnel in the ice, whose geometry and position is similar to others excavated in alpine glaciers during the Great War.

Average shear wave velocity of the plain of the province of Treviso (Northern Italy)

The accompanying map is the result of a regional survey to present average shear wave velocity in the uppermost layers (20–40 m in depth) of a large area situated in the province of Treviso, northeastern Italy. The research was conducted using the Refraction Microtremors (ReMi) seismic technique. Data from a total of 250 recording stations, scattered over an area of 2000 km2, was collected during a two months in early 2006. The final Vs map shows the tight correlation between the seismic response of the area and the structure of alluvial deposits formed during late Pleistocene and Holocene. The ReMi technique, as well as the other techniques based on the survey of the surface wave, can be valuable tools for regional mapping average values of the shear wave in near surface deposits. These data, from a seismological perspective, along with measurements of the fundamental period, represent an excellent alternative for the site modeling.

High-resolution Seismic Imaging of the Pian di Neve Glacier on the Adamello Massif (Italy)

Active seismic investigations, generally employed to image the earth interior, are also widely applied in glaciology to map the thickness of glaciers and to study the basal sediment properties. In this work we present the results of a 1-km multichannel seismic survey carried out on the Pian di Neve, a high altitude glacier located in the Adamello massif (Italy), with the purpose to image the glacier bottom and obtain the ice thickness profile. The Pian di Neve occupies a 18-km² plateau at an altitude of between 3100 and 3400 m, and together with the adjacent Mandrone glacier forms the largest glacier mass in the Italian Alps. From the maximum Little Ice Age extension to present, these two glaciers lost about 36% of their total area. The seismic survey evidenced an ice thickness ranging from 170 m to 270 m and the presence of a relatively thick layer of sediments at the bottom. Comparison with previous investigations seems to indicate that, in the last 50 years, the ice thickness in the survey area has not significantly changed. This evidence is contrary to the general retreat trend and could be due to a sort of thermal inertia in this glacial accumulation area.

Geophysical potentials in glacial and periglacial environments in the Alps.

This study analyzes the historical series of precipitation fallen along Latian coast and Abruzzo coast, and extreme rainfall in the context of climate change. Daily precipitation data cover the years ranging from 1922 to 2009 for one meteorological station, and from 1951 to 2010 for five stations. We focus on the extreme values following two approaches: the first one is based on the maximum annual daily rainfall series (1-day, 2day and 3-day) for which suitable probability distributions are fitted. The second one is based on the series of peaks over annual thresholds (POT) for which the best fitting distribution is identified. The aim of this analysis is to estimate rainfall return levels for various return periods. This is particularly helpful to the Local Administration for the urban planning and for alerting residents in metropolitan areas.

Relazioni della Campagna Glaciologica 2012. Report of the Glaciological Survey 2012.

ALLAIS Giorgia: 81; ANTONIETTI Osvaldo: 312, 314-315; BERTOGLIO Valerio: 59, 61, 67, 69, 70, 78, 79, 102, 103,109, 110, 111, 112, 113, 114, 128, 129, 130, 131, 134; BETHAZ Alberto: 248; BETTIO Marco: 180; BISOLO Andrea: 57; BORNEY Stefano: 140, 142, 143, 144, 145, 146, 147; BORRE Piero: 102, 103, 109, 110, 111, 112, 113, 114, 115, 128, 129, 130, 131; CAT-BERRO Daniele: 64, 81, 304; CERISE Stefano: 128,129, 131, 132, 133, 134; FAVRE Dario: 127.1, 127.2; FRANCESCONI Roberto: 109, 112, 113, 114; FORNENGO Fulvio: 64, 78, 79, 81; FUSINAZ Alberto: 197,198, 209, 221, 235; GADIN Gian Luigi: 232; GARINO Roberto: 189; GERARD Nicola: 134; GILLI Giulia: 86; GILLI Michelangelo: 86, 101; GIORCELLI Augusto: 281, 282, 283, 284, 285, 289; GIORCELLI Marco: 281, 282, 283, 284, 285, 289; GIULIANO Maura: 297; GODONE Danilo: 321, 322, 324, 325, 326, 327; GROSA Marco: 116; MASSA MICON Enzo: 138; MASSONI Demis: 133; MERCALLI Luca: 64, 81, 304; MIRAVALLE Raffaella: 56, 57, 58, 60, 69, 72.1, 72.2, 73, 78; MOCCAGATTA Marco: 212, 214, 216, 217, 218, 219, 223, 224, 225, 226, 227, 228, 229, 230, 231, 234, 235, 236, 238 (solo fotografie); MONTERIN Willy: 304; MORTARA Giovanni: 320; MOTTA Luigi: 278, 279, 279.1; MOTTA Michele: 279, 279.1, 280; NICOLINO Martino: 138; OSSOLA Raffaella: 357; PALOMBA Mauro: 13,20, 297; PERACINO Alberto: 140; PERONA Stefano: 13, 20; PICCINI Paolo: 304, 306, 311, 312, 314-315; POGGIO Laura: 134; POLLICINI Fabrizio: 144, 145, 146, 147, 155, 168, 172; ROGLIARDO Franco: 36, 37, 40, 41, 42, 43, 46, 47, 48, 49, 50, 51, 52; ROSSO Luciano: 2, 3, 5 ,6; TESORO Marco: 241, 246; 248; 252, 253; 253.1, 255, 256, 257, 258, 259, 260, 265, 266, 267, 268, 269; TOSATTO Elena: 70, 128, 129, 131; TRON Maurizio: 29, 34; VALISA Paolo: 349, 356, 359, 360; VALLET Valter: 139; VERGNANO Giuseppina: 59, 61, 79; VILLA VECELLA Laura: 241, 246; 248; 252, 253; 253.1, 255, 256, 257, 258, 259, 260, 265, 266, 267, 268, 269; VIOTTI Alessandro: 201, 202, 203. SETTORE LOMBARDO (LOMBARDIA SECTOR) (pagg. 304314); coordinatore (coordinator) BARONI Carlo, Università di Pisa, Dipartimento di Scienze della Terra, Via S. Maria 53, 56126 Pisa (baroni@dst.unipi.it).

Geomorphology of the El Alamein Battlefield (Southern Front, Egypt)

This map outlines the main processes and related landforms of the stretch of the Western Desert from Deir El Munassib to El Taqa Plateau, south of El Alamein (Egypt). Freely available digital elevation data derived from the Shuttle Radar Topography Mission, image processing of the Advanced Spaceborne Thermal Emission and Reflection Radiometer and field surveys have led to the geomorphological map at 1:40,000 scale. Landforms constitute the result of the complex interplay of gravitational, aeolian, coastal and fluvial processes strongly influenced by geological structure. Particular attention was devoted to the recognition, identification and mapping of military remains dating to 1942, which occur all over the study area.