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Come noto anche dalle più recenti cronache dei quotidiani l’attività solare si trova in un periodo di rapida crescita, all’interno di un ciclo periodico della durata di 11 anni. Questo si traduce nella presenza di macchie solari (Sunspot), eruzioni solari ed emissione di massa coronarica che producono campi magnetici che dalla superficie, attraverso il cosiddetto vento solare, arrivano ad alterare l’equilibrio del campo magnetico terrestre. Lo strato più periferico dell’atmosfera terrestre, la ionosfera, è il primo a subire gli effetti prodotti dall’attività solare in quanto gli ioni e le molecole ionizzate che esso continente tendono ad aumentare come numero in seguito all’attività ionizzante prodotta dal “vento solare”. La ionizzazione dello strato ionosferico, a sua volta, incide sulla propagazione dei segnali GNSS, essendo la ionosfera un mezzo dispersivo (che influenza in modo selettivo i segnali in funzione delle loro caratteristiche). Questo studio cerca di verificare quali possono essere gli effetti dell’attività solare sulle prestazioni dei servizi NRTK (Network Real Time Kinematic) attraverso l’analisi delle prestazioni raggiunte dagli utenti di un servizio di posizionamento nell’anno 2011, periodo caratterizzato da una rapida ascesa dell’attività solare verso i massimi previsti per il primo semestre del 2013. As recognized by hundreds of years of sun observation by the researcher in eliophysics, the Sun is now entering in a period of increased activity. The producing of sunspots, solar flares and coronal mass ejection from the Sun’s surface is able to create anomalies in the magnetic field that could stream towards the Earth. The terrestrial magnetic field may be influenced by the “solar wind” and the ionized upper layer of the atmosphere, called ionosphere, could be affected by scintillation and induced delays of the travelling signals. Several critical infrastructures would be influenced by such a disturbance. The 11-years long cycle of solar activity is expected to reach the peak by the middle of the year 2013 and possible effects on the GNSS (Global Navigation Satellite System) services have to be accounted for. This is because of the properties by the ionospheric layers to delay the GNSS signals depending on the electron density within the ionospheric strata. This study focuses on the effects of the ionospheric disturbance on the NRTK (Network Real Time Kinematic) services through the analysis of the performances achieved by the users during the year 2011, when a fast rising in ionospheric activity was recorded by the end of the year. A relationship between the reliability of positioning and the ionospheric activity was found.

This paper focuses on surface movements determined by geodetic methods and occurred as consequence of brine extraction from Tuzla salt deposit (Bosnia and Herzegovina). Previous studies were mainly concentrated on vertical movements, but important information about behavior of the deposit is also available from horizontal movement data. In the case of Tuzla salt deposit the geometry and spatial location of leached/empty spaces are unknown and the comparative analysis of vertical and horizontal movement could be really significant. The spatial identification of points with high values of vertical and horizontal movements depends on the geometry of empty spaces. Investigation of horizontal movements has been carried out analyzing data collected by several geodetic measurements. The results obtained by the correlated spatial analysis of vertical and horizontal movements, can identify basic geometric characteristics of the leached/empty spaces. The discussed temporal intervals are two characteristic periods, reffered to the capacity of the deposit exploitation. Movement rates per year and correlation between horizontal and vertical movements are considered as indicator parameters defining the character of ground deformation. Spatial analysis of these coefficients values has identified high risk areas, and gives additional information in thegeological structures definition.

Dune characterization in coastal zones is important for planning coastal defenses, groundwater management, and tourism development. Dune protection should be one of the main goals of any Integrated Coastal Zone Management Plan (ICZM). Coastal dunes efficiently oppose saltwater intrusion: their topographic elevation and their excellent infiltration capacity provide freshwater recharge and a hydraulic head that protect from saline intrusion according to the Ghyben-Herzberg principle (Fetter, 2001). The lateral continuity of the dunes system is also important for creating a continuous freshwater lens along the coast. As part of the Interreg IIIc Beachmed – “PosiDune project”, a monitoring campaign for groundwater levels and quality is being conducted on some test sites along stretches of the Ravenna coast: P.to Corsini, Marina Romea, Marina di Ravenna, Bevano river mouth. Dunes are still preserved in these areas and they act as natural defenses against storms, erosion and wave attack (Caruso et al., 2004; Caruso et al. 2006). A monitoring network has been established in each test site by placing piezometers both on the back and the crest of the dune and by carrying out a VES (Vertical Electri Sounding) geophysical campaign. The two methods (giving the chance to compare direct – piezometers - and indirect – geoelectric - data) has allowed to characterize the thickness of the fresh groundwater lens and the depth of the freshwater-saltwater interface. These actions have been integrated using: 1. a G.I.S. for data management; 2. a topographic and bathymetric reconstruction of the area using a LIDAR (Light detection and Ranging) survey; 3. a systematic seasonal update of the topography base and geomorphology using DGPS and theodolite surveys; 4. a survey of the geomorphologic evolution of the area through the periodical (monthly) acquisition of aerial images (flight height at 300m). The techniques employed are aimed at a precise charactetrization of the morphologic and hydrogeologic framework of the study areas. In addition, the maintenance of the monitoring system in future years will allow a better understanding of the effects of vegetation, dune restoration, and climate change to coastal hydrology and to ecosystem development (Gabbianelli & Sangiorgi, 2004; Ranjan et al. 2006). A clear comprehension of the role of dunes, achieved with this project, will be helpful for the management of the sites studied, especially considering their naturalistic values and peculiarities (they all belong to the Ramsar Zones list, SIC/ZPS sites list, Regional Po Delta Park – Emilia Romagna Region areas)

L'intenso sfruttameno dei depositi di sale sottostanti la città di Tuzla ha indotto vistosi fenomeni di subsidenza e di collassamento del terreno. A partire dal 2002 è stato effettuato un monitoraggio annuale DGPS e Remote Sensing

L’intenso sfruttamento dei depositi di sale sottostanti la città di Tuzla (Bosnia & Herzegovina) a partire dalla metà degli anni ’50, ha indotto vistosi fenomeni di subsidenza ed episodi di collassamento del terreno. Il problema ha reso necessaria un'analisi del fenomeno mediante un approccio integrato tra geometica ed analisi multicriteri dei fattori in gioco e degli elementi vulnerabili al danno.

Sinkhole development and collapse of underground caves within a gypsum substrate is focused in proximity to the beach resort of Marina di Lesina on the Adriatic coast of Southern Italy. This situation constitutes a serious geohazard for the local community and a threat to the development of the tourist activity. Fast sinkhole development has been reported in the last two decades both in terms of newly formed cavities and of widening of already existing ones. It is well known that the presence of structures, such as fault and fractures, focuses fluid flow and intensifies the dissolution and the karst evolution processes. An alignment of the sinkholes as well as their shape anisotropy, west of the harbour canal, suggests also a strong structural control.

Novel methodology to identify areas of localized deformation in a sinking urban area of Tuzla (BiH). Given that the major damage to buildings and infrastructure has been focused in areas of strain localization (surface fractures and faults), we used surface attributes to identify them. The surface attributes used are the directional, gaussian and normal curvatures computed from the cumulative subsidence surface. We compared maps of faults and fractures exposed at the surface to the curvature maps obtained with the previously mentioned methods.

L’intenso sfruttamento dei depositi di sale sottostanti la città di Tuzla (Bosnia & Herzegovina) a partire dalla metà degli anni ’50, ha indotto vistosi fenomeni di subsidenza ed episodi di collassamento del terreno. Le deformazioni del terreno conseguenti l’attività di estrazione vengono monitorate già dal 1956 grazie ai numerosissimi rilievi topografici con tecniche tradizionali effettuati su di una fitta rete topografica realizzata nell’area. Gli abbassamenti misurati nel periodo citato sono quantificabili, nelle aree maggiormente coinvolte, in una decina di metri con effetti catastrofici su buona parte dell’area storica della città e con gravi danni agli edifici, infrastrutture ed alle reti tecnologiche. A partire dal 2002, nell’ambito di una collaborazione tra municipalità di Tuzla e Provincia di Ravenna, è stato effettuato un riordino dell’enorme archivio di dati altimetrici unitamente all’introduzione di moderne tecniche di rilievo (GPS e Telerilevamento) a supporto del monitoraggio di fenomeni ancora intensi nell’area, correlati con l’attività estrattiva.

The Reno river mouth and the adjacent areas are characterized by sandy beaches, wide brackish lagoons and extended salt marshes. The study area belongs to the Po Delta Park of the Emilia Romagna Region. The study consists in a reconstruction of the coastal evolution from the beginning of the 19th century to the present. It is an analysis of the historical and geodetic cartography and of the photogrammetry. At the beginning of the XIX century the river mouth was oriented eastward but, after some human modifications to its terminal stretch, the river mouth showed a gradually northward shift, inducing the growth of a spit; in the last century the spit entered in an erosive phase, which caused the reduction and the thinning of its shape. At the same time the northward movement of the sediment coming from the Reno river caused the occlusion of the outlet of the Bellocchio Channel inducing a decrease of water exchange between the “Sacca di Bellocchio” and the Adriatic sea. From a naturalistic point of view, the “Sacca di Bellocchio” is one of the most important area of the Po Delta Park; the worrying forecasts for the next decades give uncertain expectation for this esteemed, sensitive ecosystem. The territorial setting suggests the possibility of increased intensification of flooding events, the amplifications of beach erosion, an instability in the water circulation and an enhanced intrusion of the saline wedge into the channels and into the coastal aquifers. Even in a short-term scale, all the above factors will be able to significantly modify this ecosystem.

The analisys of the huge dataset of altimetric data, the correlation with the boreholes activities and the introduction of more productive modern technologies (satellite GPS for geodesy) for repeated land monitoring are the object