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A considerable amount of the plastics produced around the world is now dispersed throughout the environment, and in particular in aquatic ecosystems. This can have damaging consequences for plants, animals and human beings. This study investigates some approaches for detection and monitoring of plastics waste in river habitats through multispectral image classification. The data are acquired using a proximity sensor in the electromagnetic spectrum range that includes the ultraviolet, visible and near infrared bands, as for the WorldView-2 satellite. The in-depth analysis of the spectral signatures obtained shows typical plastics trends and reflectance values in the near infrared bands. Different classification methods were compared to test their effectiveness for the isolation of plastics samples dispersed in a river habitat. This project represents the first step within a wider research programme, with the aim to define a new approach for future river pollution monitoring.

Tra il 1922 e il 1953 Pietro Zangheri realizzò un plastico di circa 20 mq rappresentante tutto il territorio della Romagna per un’estensione di circa 6400 Kmq, secondo gli studi dello stesso Zangheri. Il plastico fu realizzato in modo rigoroso su base cartografica dell’Istituto Geografico Militare Italiano (IGMI) utilizzando direttamente le tavolette in scala 1:25000. Il plastico, di proprietà del museo civico di storia naturale di Verona è esposto stabilmente a Santa Sofia (FC) presso la sede del Parco Nazionale delle Foreste Casentinesi, Monte Falterona e Campigna. Nel 1998 il plastico subì un’accurata opera di restauro che lo riportò agli splendori originari. Si è voluto realizzare un modello virtuale tridimensionale del plastico utilizzando la tecnica fotogrammetrica. È stato riprodotto in scala, simulando, un volo fotogrammetrico aereo. Attraverso un processamento rigoroso delle immagini acquisite e utilizzando una serie cospicua di punti di controllo “a terra” misurati e di coordinate note, è stato realizzato il modello tridimensionale del plastico. Quest’ultimo verrà confrontato sulla base dell’orografia attuale mediante modelli tridimensionali recenti per iniziare a comprendere su scala regionale innanzi tutto la validità metrica dell’opera di Zangheri e per evidenziare specifiche variazioni morfologiche del territorio.

Plastic pollution has become one of the main global environmental emergencies. A considerable part of used plastics materials is dispersed or accumulated in the environment with a significant damaging impact on many terrestrial and aquatic ecosystems.Artificial Intelligence has proven a fundamental approach in last years for the detection of plastics waste in the aquatic habitats: several groups have recently tried to tackle such problem by developing some machine learning-based methods and multispectral or RGB imagery. This study compares the results obtained by two machine learning classifiers, namely Random Forests and Support Vector Machine, to detect macroplastic in the fluvial habitat through multispectral imagery. The acquisition of images has been made with a hand-held multispectral camera called MAIA-WV2. Despite the obtained results are quite good in terms of accuracy in a random validation dataset, some issues, mostly related to the presence of white rocks and glares on water have still to be properly solved.

In Antarctica, the severe climatic conditions and the thick ice sheet that covers the largest and most internal part of the continent make it particularly difficult to systematically carry out geophysical and geodetic observations on a continental scale. It prevents the comprehensive understanding of both the onshore and offshore geology as well as the relationship between the inner part of East Antarctica (EA) and the coastal sector of Victoria Land (VL). With the aim to reduce this gap, in this paper multiple geophysical dataset collected since the 1980s in Antarctica by Programma Nazionale di Ricerche in Antartide (PNRA) were integrated with geodetic observations. In particu-lar, the analyzed data includes: (i) Geodetic time series from Trans Antarctic Mountains DEFormation (TAMDEF), and Victoria Land Network for DEFormation control (VLNDEF) GNSS stations installed in Victoria Land; (ii) the integration of on-shore (ground points data and airborne) gravity measurements in Victoria Land and marine gravity surveys performed in the Ross Sea and the nar-row strip of Southern Ocean facing the coasts of northern Victoria Land. Gravity data modelling has improved the knowledge of the Moho depth of VL and surrounding the offshore areas. By the integration of geodetic and gravitational (or gravity) potential results it was possible to better con-strain/identify four geodynamic blocks characterized by homogeneous geophysical signature: the Southern Ocean to the N, the Ross Sea to the E, the Wilkes Basin to the W, and VL in between. The last block is characterized by a small but significant clockwise rotation relative to East Antarctica. The presence of a N-S to NNW-SSE 1-km step in the Moho in correspondence of the Rennick Geo-dynamic Belt confirms the existence of this crustal scale discontinuity, possibly representing the tectonic boundary between East Antarctica and the northern part of VL block, as previously pro-posed by some geological studies.

Within coastal systems, sand dunes are the only natural barriers able to counteract erosive processes. Since their equilibrium is often threatened by human activities and high vulnerability of the coastal environment, dunes require increasing attention and specific monitoring. Located between the mainland and the sea, dunes are unique residue habitats for some plant and animal species. In particular, their vegetation is important because it has a consolidation function and promotes the vertical dune accretion. A georeferenced vegetation classification can be useful to define the advancements or erosion stage of the dune, usually based only on the geometric reconstruction. The proposed study aims to compare the classifications performed with some combinations of two of the last generation sensors and traditional image processing techniques. High spectral resolution satellite image (WorldView-2) and a multispectral orthophoto, obtained from data acquired by an unmanned aerial vehicle, were used. Objects and pixel algorithms were applied and the results were compared by a statistical test. Using the same bands, the findings show that both data are suitable for monitoring the evolutionary dune status. Specifically, the WorldView-2 pixel-based classification and UAV object-based classification provide the same accurate results.

GNSS networks in Antarctica are a fundamental tool to define actual crustal displacements due to geological and geophysical processes and to constrain the glacial isostatic models (GIA). A large network devoted to the detection and monitoring of crustal deformations in the Northern Victoria Land (Victoria Land Network for DEFormation control – VLNDEF), was monumented during the 1999–2000 and 2000–2001 field campaigns, as part of Italian National Program for Antarctic Research and surveyed periodically during the Southern summer seasons. In this paper, GPS observations of VLNDEF collected over a more than 15-year span, together with various selected POLENET sites and more than 70 IGS stations, were processed with Bernese Software, using a classical double difference approach. A solution was obtained combining NEQs by means of ADDNEQ2/FODITS tools embedded in Bernese Software. All the Antarctic sites were kept free and a subset of 50 IGS stations were used to frame VLNDEF into ITRF2008. New evidence provided by analysis of GPS time series for the VLNDEF network is presented; also displacements along the vertical component are compared with the recently published GIA models. The absolute velocities indicate an overall displacement of the northern Victoria Land region along the south-east direction (Ve = 10.6 mm/yr, Vn = −11.5 mm/yr) and an average uplift rate of Vu = 0.5 mm/yr. Two GIA models have been analyzed: ICE-6G_C-VM5a proposed by Argus et al. (2014), Peltier et al. (2015) and W12A_v1 by Whitehouse et al. (2012a,b). Up rates, predicted over the VLNDEF sites by the mentioned GIA models, have been extracted and compared with those observed. A preliminary comparison with GPS-derived vertical rates shows that the Victoria Land ICE-6G_C-VM5 and W12A_v1 GIA models predict overestimated uplift rates of 0.7 and 0.9 mm/yr weighted mean residuals respectively. The mean horizontal relative motions within the Victoria Land (VL) area are in most cases negligible, while only a few points exhibit horizontal velocities greater than the confidence level. Such a residual horizontal velocity field could represent some of the tectonic characteristics affecting VL, characterized by block faulting, tilting along NE striking and SE dipping extensional faults. Uplift rates, highlighted in the present paper depict a well defined spatial pattern in the investigated areas. Northward, all sites show a general positive trend up to 2.3 mm/yr. In the central and southern areas small negative trends (up to −1.3 mm/yr) were detected in the vertical displacements. Only the site VL06, located atop the Mt. Melbourne volcano, does not concord with such a general reading, as it is representative of the volcanic complex’s evolution. Observed and predicted uplift rates increase westward (inland) where the ice-load increases. The same behavior is predicted southward by the GIA models; whereas GPS values decrease toward the south pole, due to the movements of a few sites reflecting the neotectonic phenomena acting in the Victoria Land region.

In recent years digital sensors have been successfully integrated on board Unmanned Aerial Vehicles (UAV) to assess crop vigour, vegetation coverage, and to quantify the ‘greenness’ of foliage as indirect measurements of crop nitrogen status. The classical approach of precision agriculture has involved the use of multispectral sensors onboard UAV and the development of numerous vegetation indices associated with vegetation parameters, such as the mostly used Normalized Difference Vegetation Index (NDVI). However, the main negative issue when dealing with multi and hyperspectral reflectance measuring tools is their high cost and complexity from the operational point of view. As a low-cost alternative, vegetation indices derived from Red Green Blue (RGB) cameras have been employed for remote-sensing assessment, providing data on different stress conditions and species. Digital images record information as amounts of RGB light emitted for each pixel of the image; however, the intensity of red and blue will often alter how green an image appears. To simplify the interpretation of digital colour data, recent studies have suggested converting RGB values to the more intuitive Hue, Saturation, and Brightness (HSB) colour spectrum, and then into a single measure of dark green colour, the Dark Green Color Index (DGCI). In this study, NDVI acquired by a ground-based handheld crop sensor and by a multispectral camera mounted on board a UAV has been compared with DGCI calculated from images taken with a commercial digital camera on board a UAV, trying to quantify the colour of turfgrass that had received different nitrogen (N) rates. The objectives of the trial were to study an affordable easy-to-use tool evaluating the relationship among NDVI, DGCI and leaf nitrogen content on turfgrass.

The feasibility of unmanned-aerial-vehicle-based photogrammetry was assessed for the reconstruction of high-resolution topography and geomorphic features of quarries by nadir and off-nadir imagery. The test site was a quarry located in the rural area of Turi (Bari, southern Italy). Two processing scenarios were created. Nadir images were initially used, and images acquired with off-nadir angles were added. An accurate set of ground control points (GCPs) were surveyed for both georeferencing purposes and validation processes. In the reconstruction of the surfaces, an accuracy of a few centimeters was achieved in the final positioning of point clouds representing the main geometries of quarry environment. However, greatest differences were found along the edges or the lines characterized by sudden slope changes. To better understand such results, some characteristic quarry shapes depicted by both the scenarios were compared to those surveyed by a total station used as an independent benchmark technique. It allowed to define the benefits introduced by the joint use of nadir and oblique images in the delineation of quarry shapes, surface discontinuities and better descriptions of sub-vertical walls. Beside the evaluation of benefits introduced by use of oblique cameras, the effectiveness of the proposed methodology was also discussed with alternative technologies. Unmanned aerial platforms represent an effective solution, with the need for few accurate GCPs.

Archaeologists can increasingly profit from digital elevation models for study and analysis of the actual landscape, which can contain signs of the past or mirror the ancient landscapes. From among the techniques available for such analyses, a photogrammetric method was chosen here that used images acquired by an unmanned aerial vehicle and involved structure-from-motion algorithms during the process. These methods were selected because as the state-of-the-art of the discipline they are in the initial stages and are under continuous evolution. Furthermore, they provided us with the possibility of rapid, highly automated, and also low-cost, production of high-resolution three-dimensional data. This test was carried out on the Roman site of Burnum (Croatia). It focused on the comparison between the digital surface model created using an unmanned aerial vehicle with a structure-from-motion approach, and the digital terrain model already built through a kinematic Global Navigation Satellite System survey. The results of the validation provided a final vertical accuracy of about 10 cm, which was achieved in specific areas where there were no trees, bushes and high grass. Through the resulting digital terrain models, archaeologists can provide vital support for important hypothesis regarding the ancient environment.

Recent advances in automation of photogrammetric 3D modelling software packages have stimulated interest in reconstructing highly accurate 3D object geometry in unconventional environments such as underwater utilizing simple and low-cost camera systems. The accuracy of underwater 3D modelling is affected by more parameters than in single media cases. This study is part of a larger project on 3D measurements of temporal change of coral cover in tropical waters. It compares the accuracies of 3D point clouds generated by using images acquired from a system camera mounted in an underwater housing and the popular GoPro cameras respectively. A precisely measured calibration frame was placed in the target scene in order to provide accurate control information and also quantify the errors of the modelling procedure. In addition, several objects (cinder blocks) with various shapes were arranged in the air and underwater and 3D point clouds were generated by automated image matching. These were further used to examine the relative accuracy of the point cloud generation by comparing the point clouds of the individual objects with the objects measured by the system camera in air (the best possible values). Given a working distance of about 1.5 m, the GoPro camera can achieve a relative accuracy of 1.3 mm in air and 2.0 mm in water. The system camera achieved an accuracy of 1.8 mm in water, which meets our requirements for coral measurement in this system., International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, XLI (B5), ISSN:1682-1750, ISSN:2194-9034, ISSN:1682-1777

In order to make inferences on the geodynamics of Antarctica, geodetic and gravimetric maps derived from past and new observations can be used. This paper provides new insights into the geodynamics of Antarctica by integrating data at regional and continental scales. In particular, signatures of geodynamic activity at a regional extent have been investigated in Victoria Land (VL, Antarctica) by means of Global Navigation Satellite System (GNSS) permanent station observations, data from the VLNDEF (Victoria Land Network for Deformation control) discontinuous network, and gravity station measurements. At the continental scale, episodic GNSS observations on VLNDEF sites collected for 20 years, together with continuous data from the International GNSS Service (IGS) and Polar Earth Observing Network (POLENET) sites, were processed, and the Euler pole position assessed with the angular velocity of the Antarctic plate. Both the Bouguer and the free-air gravity anomaly maps were obtained by integrating the available open-access geophysics dataset, and a compilation of 180 gravity measurements collected in the VL within the Italian National Program for Antarctic Research (PNRA) activities. As a result, new evidence has been detected at regional and continental scale. The main absolute motion of VL is towards SE (Ve 9.9 &plusmn, 0.26 mm/yr, Vn &minus, 11.9 &plusmn, 0.27 mm/yr) with a pattern similar to the transforms of the Tasman and Balleny fracture zones produced as consequence of Southern Ocean spreading. Residual velocities of the GNSS stations located in VL confirm the active role of the two main tectonic lineaments of the region, the Rennick&ndash, Aviator and the Lillie&ndash, Tucker faults with right-lateral sense of shear. The resulting VL gravity anomalies show a NW region characterized by small sized Bouguer anomaly with high uplift rates associated and a SE region with low values of Bouguer anomaly and general subsidence phenomena. The East and West Antarctica are characterized by a different thickness of the Earth&rsquo, s crust, and the relative velocities obtained by the observed GNSS data confirm that movements between the two regions are negligible. In East Antarctica, the roots of the main subglacial highlands, Gamburtsev Mts and Dronning Maud Land, are present. The Northern Victoria Land (NVL) is characterized by more scattered anomalies. These confirm the differences between the Glacial Isostatic Adjustment (GIA) modeled and observed uplift rates that could be related to deep-seated, regional scale structures.

The new era of designing in architecture and civil engineering applications lies in the Building Information Modeling (BIM) approach, based on a 3D geometric model including a 3D database. This is easier for new constructions whereas, when dealing with existing buildings, the creation of the BIM is based on the accurate knowledge of the as-built construction. Such a condition is allowed by a 3D survey, often carried out with laser scanning technology or modern photogrammetry, which are able to guarantee an adequate points cloud in terms of resolution and completeness by balancing both time consuming and costs with respect to the request of final accuracy. The BIM approach for existing buildings and even more for historical buildings is not yet a well known and deeply discussed process. There are still several choices to be addressed in the process from the survey to the model and critical issues to be discussed in the modeling step, particularly when dealing with unconventional elements such as deformed geometries or historical elements. The paper describes a comprehensive workflow that goes through the survey and the modeling, allowing to focus on critical issues and key points to obtain a reliable BIM of an existing monument. The case study employed to illustrate the workflow is the Basilica of St. Stefano in Bologna (Italy), a large monumental complex with great religious, historical and architectural assets.

Multispectral imaging is a widely used remote sensing technique, whose applications range from agriculture to environmental monitoring, from food quality check to cultural heritage diagnostic. A variety of multispectral imaging sensors are available on the market, many of them designed to be mounted on different platform, especially small drones. This work focuses on the geometric and radiometric characterization of a brand-new, lightweight, low-cost multispectral camera, called MAIA. The MAIA camera is equipped with nine sensors, allowing for the acquisition of images in the visible and near infrared parts of the electromagnetic spectrum. Two versions are available, characterised by different set of band-pass filters, inspired by the sensors mounted on the WorlView-2 and Sentinel2 satellites, respectively. The camera details and the developed procedures for the geometric calibrations and radiometric correction are presented in the paper.

A private network of 133 Global Navigation Satellite Systems (GNSS) permanent sites, named ItalPoS (ItalianPositioning Service) and uniformly covering the entire Italian territory, was established in April 2006 by the ItalianDivision of Leica Geosystems S.p.A. This network also involves several GPS stations of the INGV (ItalianNational Institute of Geophysics and Volcanology) RING (Real-time Integrated National Gps) network and GPSstations from other public and private bodies. Indeed Leica Geosystems contributed with its experience and itsproducts to these networks which currently fulfil the national coverage where there are no ItalPoS stations. Forinstance, the purpose of the ItalPoS network is mainly GNSS data distribution in terms of real time correctionsand RINEX files for the post-processing.In order to compute and distribute to private and scientific users a set of adjusted coordinates of the ItalPoS networkin the IGS05 and ETRF89-2000 reference frames, a dataset of RINEX of about 120 GPS permanent siteswas created and processed, using the distributed sessions approach, by means of Gamit/Globk 10.3 GPS dataprocessor, also using some SOPAC (Scripps Orbits and Permanent Array Center) and EUREF (European PermanentNetwork) solutions to improve the reference frame definition and the internal constraints.This paper describes all the strategies adopted to estimate coordinates and velocities of the ItalPoS Network inIGS05 and in ETRF89-2000 reference frames in the whole Italian territory.

The availability of high-resolution Digital Surface Models of coastal environments is of increasing interest for scientists involved in the study of the coastal system processes. Among the range of terrestrial and aerial methods available to produce such a dataset, this study tests the utility of the Structure from Motion (SfM) approach to low-altitude aerial imageries collected by Unmanned Aerial Vehicle (UAV). The SfM image-based approach was selected whilst searching for a rapid, inexpensive, and highly automated method, able to produce 3D information from unstructured aerial images. In particular, it was used to generate a dense point cloud and successively a high-resolution Digital Surface Models (DSM) of a beach dune system in Marina di Ravenna (Italy). The quality of the elevation dataset produced by the UAV-SfM was initially evaluated by comparison with point cloud generated by a Terrestrial Laser Scanning (TLS) surveys. Such a comparison served to highlight an average difference in the vertical values of 0.05 m (RMS = 0.19 m). However, although the points cloud comparison is the best approach to investigate the absolute or relative correspondence between UAV and TLS methods, the assessment of geomorphic features is usually based on multi-temporal surfaces analysis, where an interpolation process is required. DSMs were therefore generated from UAV and TLS points clouds and vertical absolute accuracies assessed by comparison with a Global Navigation Satellite System (GNSS) survey. The vertical comparison of UAV and TLS DSMs with respect to GNSS measurements pointed out an average distance at cm-level (RMS = 0.011 m). The successive point by point direct comparison between UAV and TLS elevations show a very small average distance, 0.015 m, with RMS = 0.220 m. Larger values are encountered in areas where sudden changes in topography are present. The UAV-based approach was demonstrated to be a straightforward one and accuracy of the vertical dataset was comparable with results obtained by TLS technology.

Unmanned Aerial Vehicles (UAV)-based remote sensing offers great possibilities to acquire in a fast and easy way field data for precision agriculture applications. This field of study is rapidly increasing due to the benefits and advantages for farm resources management, particularly for studying crop health. This paper reports some experiences related to the analysis of cultivations (vineyards and tomatoes) with Tetracam multispectral data. The Tetracam camera was mounted on a multi-rotor hexacopter. The multispectral data were processed with a photogrammetric pipeline to create triband orthoimages of the surveyed sites. Those orthoimages were employed to extract some Vegetation Indices (VI) such as the Normalized Difference Vegetation Index (NDVI), the Green Normalized Difference Vegetation Index (GNDVI), and the Soil Adjusted Vegetation Index (SAVI), examining the vegetation vigor for each crop. The paper demonstrates the great potential of high-resolution UAV data and photogrammetric techniques applied in the agriculture framework to collect multispectral images and evaluate different VI, suggesting that these instruments represent a fast, reliable, and cost-effective resource in crop assessment for precision farming applications.

The 3D reconstruction with a metric content of a submerged area, where objects and structures of archaeological interest are found, could play an important role in the research and study activities and even in the digitization of the cultural heritage. The reconstruction of 3D object, of interest for archaeologists, constitutes a starting point in the classification and description of object in digital format and for successive fruition by user after delivering through several media. The starting point is a metric evaluation of the site obtained with photogrammetric surveying and appropriate 3D restitution. The authors have been applying the underwater photogrammetric technique since several years using underwater digital cameras and, in this paper, digital low cost cameras (off-the-shelf). Results of tests made on submerged objects with three cameras are presented: © Canon Power Shot G12, © Intova Sport HD e © GoPro HERO 2. The experimentation had the goal to evaluate the precision in self-calibration procedures, essential for multimedia underwater photogrammetry, and to analyze the quality of 3D restitution. Precisions obtained in the calibration and orientation procedures was assessed by using three cameras, and an homogeneous set control points. Data were processed with © Agisoft Photoscan. Successively, 3D models were created and the comparison of the models derived from the use of different cameras was performed. Different potentialities of the used cameras are reported in the discussion section. The 3D restitution of objects and structures was integrated with sea bottom floor morphology in order to achieve a comprehensive description of the site. A possible methodology of survey and representation of submerged objects is therefore illustrated, considering an automatic and a semi-automatic approach.

Monitoring the time history of structures and infrastructures has always been an important area of application of geodetic and geomatic methods. Here we shall concentrate on the item of monitoring ancient buildings because, beyond its intrinsic interest, it provides a good illustration of some of the most recent monitoring techniques. Identifying the overhang, progressive changes of inclination, differential movements of the structure and detailing the study of structural elements are just some examples of the many fundamental and necessary information for structural engineers. Those data are required to study and analyze the behavior of a structure with the purpose to assess the stability. Looking at the several methods offered by Geomatics, laser scanning appears to be the best technology to provide an effective 3D solution to those requirements. Surveying by means of a terrestrial laser scanner, allows to detect a huge number of 3D information with high accuracy in a relatively short time and high accuracy. Just analyzing the point clouds, interesting information along with useful products can be obtained in order to draw some considerations about the investigated structure. This research aims at suggesting a new philosophy for using 3D models in a diagnostic perspective in order to study structures along with their actual dimensions, their stability and so on. Traditionally, indeed, laser scanning is chosen for artistic and architectural studies and the resulting three-dimensional model represents what often is of concern. Furthermore, the use of more classic techniques, such as total station and digital leveling, and LST is fundamental as an integrated approach for the monitoring of ancient buildings. The integration of different techniques allow a redundancy of observation and the possibility to verify the results obtained form independent techniques as is shown throughout some experimental applications.

Within the Italian Antarctic research programme repeated GPS-measurements are being carried out at well installed points in the area of Northern-Victoria-Land (NVL), Antarctica, called VLNDEF: Victoria Land Network for Deformation Control. Although the deformations obtained over a period of 4 years are quite small we consider micro-gravity measurement a suitable complement for geodynamic research. Since the German Federal Institute for Geosciences and Natural Resources (BGR) is active in that area as well, until the year 2010 performing nine expeditions comprising geological and geophysical work, we used the offer to join expedition GANOVEX X during the season 2009/2010. With three gravimeters 13 points of the Italian network near the German station Gondwana were observed. The advantage of such measurements is that they do not require topographic corrections. Thus, the instrumental resolution and the measurement conditions, resp., are the limits for the resolution and accuracy of the measurements. In order to receive a reliable data base we used three well calibrated gravimeters in parallel and repeated the measurements several times. Local effects due to changes of the ice cover and snow fall are below the achieved measurement accuracy, because the points are so exposed that local effects are negligible. Although the elevation differences up to more than 2,700 m are quite strong, the results reveal the feasibility of these measurements in that area: The obtained standard deviations are in the order of ±10 to ±20 μGal.

Satellite images are a tool increasingly used in environmental monitoring and in recent years have become also strongly used in the field of archaeology. In this study it was conducted an experimental analysis on the identification of wetlands from satellite images in order to identify sites of interest from the archaeological point of view because probable sites of ancient settlements. The studied area is the Plan de la Limagne which is located in North-East of the French city of Clermont-Ferrand. For wet areas identification were used two ASTER satellite images and pre-existing carthography. Different indexes have been used to identify wet areas. First of all, it was used the NDVI (Normalized Difference Vegetation Index) to discriminate bare soils. Secondly, through the Tasseled Cap transform, other indexes were obtained, such as the Greeness Index, the Brightness Index (SBI – Soil Brightnes Index) and the Wetness Index. Then it has been used the ATI index (Apparent Thermal Inertia) that provides information on the thermal inertia of soils. Through these indexes, visual inspection and the study of spectral signatures, it has been tried not only to identify wetlands within the images, but also to find repeatable processes for the detection of these areas. Some “anomalous” areas, that are probably wet areas, have been identified with this procedure. The identification of wet areas has been carried out in a raw way, this is surely a first approximation analysis. Certainly the in situ analysis would provide the possibility of a better evaluation, in fact field measurements could be used to calibrate the model and then find an effective and repeatable procedure for identifying wetlands.

Among the many open-source software solutions recently developed for the extraction of point clouds from a set of un-oriented images, the photogrammetric tools Apero and MicMac (IGN, Institut Géographique National) aim to distinguish themselves by focusing on the accuracy and the metric content of the final result. This paper firstly aims at assessing the accuracy of the simplified and automated calibration procedure offered by the IGN tools. Results obtained with this procedure were compared with those achieved with a test-range calibration approach using a pre-surveyed laboratory test-field. Both direct and a-posteriori validation tests turned out successfully showing the stability and the metric accuracy of the process, even when low textured or reflective surfaces are present in the 3D scene. Afterwards, the possibility of achieving accurate 3D models from the subsequently extracted dense point clouds is also evaluated. Three different types of sculptural elements were chosen as test-objects and "ground-truth" data were acquired with triangulation laser scanners. 3D models derived from point clouds oriented with a simplified relative procedure show a suitable metric accuracy: all comparisons delivered a standard deviation of millimeter-level. The use of Ground Control Points in the orientation phase did not improve significantly the accuracy of the final 3D model, when a small figure-like corbel was used as test-object.

A semipermanent Global Positioning System (GPS) network of 30 vertices known as the Victoria Land Network for Deformation Control (VLNDEF) was set up in the Austral summer of 1998 in northern Victoria Land (NVL), including Terra Nova Bay (TNB), Antarctica. The locations were selected according to the known Cenozoic fault framework, which is characterized by a system of NW‐SE regional faults with right‐lateral, strike‐slip kinematics. The TNB1 permanent GPS station is within the VLNDEF, and following its installation on a bedrock monument in October 1998, it has been recording almost continuously. The GPS network has been surveyed routinely every two summers, using high‐quality, dual‐frequency GPS receivers. In this study we present the results of a distributed session approach applied to the processing of the GPS data of the VLNDEF. An improved reference frame definition was implemented, including a new Euler pole, to compute the Antarctic intraplate residual velocities. The projection of the residual velocities on the main faults in NVL show present‐day activities for some faults, including the Tucker, Leap Year, Lanterman, Aviator, and David faults, with right‐lateral strike‐slip kinematics and local extensional and compressional components. This active fault pattern divides NVL into eight rigid blocks, each characterized by its relative movements and rigid rotations. These show velocities of up to several millimeters per year, which are comparable to those predicted by plate tectonic theory at active plate margins.

Ice streams play a major role in the ice mass balance and in the reckoning of the global sea level; they have therefore been object of wide scientific interest in the last three decades. During the 21st Italian Antarctic Expedition, in the austral summer 2005–06, we deployed a joint seismographic and geodetic network in the area of the David Glacier, Southern Victoria Land. This campaign followed a similar experiment carried out in the same area during the austral summer 2003–04 with the deployment of a seismographic network that recorded significant microseismicity beneath the David Glacier, primarily occurring as a few small clusters. In the latest 2005–06 deployment, 7 seismographic stations and 3 GPS geodetic receivers operated continuously for a period of 3 months (November 2005–early February 2006) in an area of about 100×150 km2 around the David Glacier. We have carried out several analyses using the combined data sets. These included the examination of the temporal evolution in earthquake magnitude and location and also the contemporaneous observation of both seismic activity and surface kinematics of the ice stream to possibly correlate the recorded microseismicity with the movement of the glacier, affected by the Ross Sea tides. Unfortunately, a clear correlation between the occurrence of seismic events and the movement of the glacier is not evident. Here we present some details of the two temporary networks and preliminary results and implications.

Scientific investigations in Antarctica are, for many different reasons, a challenging and fascinating task. Measurements, observations and field operations must be carefully planned well in advance and the capacity of successfully meeting the goals of a scientific project is often related to the capacity of forecasting and anticipating the many different potential mishaps. In order to do that, experience and logistic support are crucial. On the scientific side, the team must be aware of its tasks and be prepared to carry out observations in a hostile environment: both technology and human resources have to be suitably selected, prepared, tested and trained. On the logistic side, nations, institutions and any other organisation involved in the expeditions must ensure the proper amount of competence and practical support.

A semi-permanent GPS network of about 30 vertices has been installed at Terra Nova Bay (TNB) near Ross Sea in Antarctica. A permanent GPS station TNB1 based on an Ashtech Z-XII dual frequency P-code GPS receiver with ASH700936D_M Choke Ring Antenna has been mounted on a reinforced concrete pillar built on bedrock since October 1998 and has recorded continuously up to the present. The semi-permanent network has been routinely surveyed every summer using high quality dual frequency GPS receivers with 24 hour sessions at 15 sec rate; data, metadata and solutions will be available to the scientific community at (http://www.geodant.unimore.it). We present the results of a distributed session approach applied to processing GPS data of the TNB GPS network, and based on Gamit/Globk 10.2-3 GPS analysis software. The results are in good agreement with other authors' computations and with many of the theoretical models. Citation: Casula, G., M. Dubbini, and A. Galeandro (2007), Modeling environmental bias and computing velocity field from data of Terra Nova Bay GPS network in Antarctica by means of a quasi-observation processing approach, in Antarctica: A Keystone in a Changing World - Online Proceeding of the 10 th

Identifying the overhang, progressive changes of inclination, differential movements of the structure and detailing the study of structural elements are just some examples of the many fundamental information for structural engineers. Those data are required to study and analyze the behavior of a structure with the purpose to assess the stability . Laser scanning appears to be the best technology to provide an effective solution to those requirements. Surveying by means of a terrestrial laser scanner (TLS), allows to detect a huge number of information with relatively short time and high accuracy. Those data, then, do not necessarily need to be used to reconstruct the three dimensional surface model. Just analyzing the point clouds, interesting information along with useful products can be obtained in order to draw some considerations about the investigated structure. This research aims to suggest a new philosophy for using TLS in a diagnostic perspective in order to study structures along with their actual dimensions, their stability and so on. This new approach, characterized by a welladvanced vision, is really different from the traditional one because of the engineering point of view with respect to the usual application of TLS. Traditionally, indeed, laser scanning is chosen for artistic and architectural studies and the resulting three-dimensional model represents what often is of concern. The research focuses on the Cathedral of Modena, one of the most important pieces of Romanesque culture in Europe (UNESCO World Heritage List since 1997). The overall motivation of this research is to preserve the cultural heritage we are responsible for, as long as spectators. Thus, the final purpose is to illustrate the methodology to compute anomalies in structural geometry by means of TLS in order to provide an accurate description of the structure that is particularly useful for structural engineers, architects and art historians. Both outdoor as well as indoor TLS surveys were performed. The geometry of the structure was properly described by analyzing point clouds; specific measurements were focused on constituent elements with the aim of detecting anomalies of the geometric configuration. Geometric anomalies might be read as the result of deformations occurred in the past or as future deformations due to an abnormal geometric configuration. Investigations about the identified anomalies will be presented together with differential movements obtained by high precision leveling focused on a network of benchmarks that were installed along the outside perimeter. The integration of independent techniques allows to check for consistency of results.

We had the opportunity to make surveying of some middle age towers located in Emilia Romagna region (Italy): Ghirlandina tower (Modena), “Della Sagra” tower (Carpi, Modena) , Asinelli tower (Bologna). Those towers are very interesting by architectural and artistic point of view; Ghirlandina and Asinelli are Cultural Heritage site of UNESCO. Terrestrial laser scanner (TLS) instrument has been used with an accuracy at 1 cm level in order to obtain good restitution in absolute coordinates, even with a precise topographic determination of GCP (Ground Control Points). Tridimensional restitution of the towers is here presented; we would like to point out the attention on the way that we use the TLS for enhancing the geometrical characteristics, particularly the height of the towers and the axis development that were determined through the trajectory of barycenter of transversal sections. The determination of actual geometry is essential for the study of the buildings and it is a first fundamental step for monitoring the towers.