Anna Rampini

INO - Istituto Nazionale di Ottica, Florens, Tuscany, Italy

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Publications (79)56.5 Total impact

  • G. Bordogna · P. Carrara · L. Criscuolo · M. Pepe · A. Rampini
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    ABSTRACT: Despite Volunteered Geographic Information (VGI) activities are now extremely helpful in a number of scientific applications, researchers and decision makers oppose some resistance to the usage of volunteered contributions, due to quality issues. Several methods and workflows have been proposed to face quality issues in different VGI projects, usually built ad-hoc for specific datasets, thus resulting neither extensible nor transferable. In order to overcome this weakness, the authors propose to perform an user-driven assessment on VGI items in order to filter only those that satisfy minimally acceptable quality levels defined according to their specific quality requirements and project goals. In the present work the users, i.e., information consumers, are seen as decision makers and are allowed to set the minimum acceptable quality levels Thus the approach proposes a user driven assessment of the fitness for use of VGI items. The paper first briefly presents a view on VGI components and suitable quality indices, then it describes a logic architecture for managing them and for enabling a querying mechanism to the datasets. The approach is finally exemplified with a case study simulation.
    No preview · Article · Aug 2015
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    ABSTRACT: Initiatives that rely upon the contributions of volunteers to reach a specific goal are growing more and more with the success of Web 2.0–interactive applications. Also scientific projects are testing and exploiting volunteers' collaboration, but the quality of information obtained with this approach is often puzzling. This paper offers a rich overview of many scientific projects where geographic contributions are committed to volunteers, to the aim of defining strategies to improve information quality. By describing real examples of Volunteer Geographic Information (VGI), the contribution establishes a categorization based on the characteristics of the information, tasks, and scopes of the projects. After a discussion on the relationships of categories and VGI quality, the paper analyses techniques to improve the quality of volunteered information according to the moment of its assessment (i.e., ex ante, ex post, or both with respect to information creation). The paper outlines the main limitations of the different approaches and indicates some guidelines for future developments.
    No preview · Article · Nov 2014 · International Journal of Digital Earth
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    E. Binaghi · P.A. Brivio · P. Ghezzi · A. Rampini · E. Zilioli
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    ABSTRACT: Ce papier propose une étude expérimentale pour analyser en profondeur comment deux techniques de classification non-conventionnelles, entre les plus couramment utilisées, basées sur les ensembles flous et sur les réseaux artificiels de neurones, peuvent contribuer à déterminer l'appartenance partielle aux classes de couverture du sol. Deux expériences ont été conduites pour achever cet objectif. Dans le premier on utilise des images artificielles simulées qui contiennent des pixels purs et des pixels mixes dont on connaît parfaitement la géometrie et la radiométrie (position et distribution des couvertures du sol au niveau de souspixel pour chaque pixel, comme ensemble complet de vérité-terrain). Dans deuxième expérience on examine une image satellitaire de la lagune de Venise (Italie) qui est caractérisée par un haut degré de complexité car les eaux et les wetland se mélangent les uns dans les autres, dessinant une composition emmelée et toujours changeante. La précision des résultats des deux techniques de classification a été évaluée et comparée parmi des outils d'évaluation qui ont été définis et développés à fin d'étendre les estimateurs traditionnels, soit descriptifs soit analytiques, dans le domaine propre des classes caractérisées par les degrés d'appartenance partielle. Les mesures de précision regardent l'identification de la composante dominante et des compositions de la mixture, l'ordination par pourcentage des composantes de la mixture et l'estimation de leur étendue. Une comparaison a été aussi établie avec la technique basée sur le modèle linéaire de mixture pour évaluer si les deux techniques non-conventionelles offrent être une alternative valide.
    Full-text · Article · Jul 2014 · Canadian Journal of Remote Sensing
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    ABSTRACT: The paper analyses the challenges and problems posed by the use of Volunteered Geographic Information (VGI) in citizen science and a proposal is formulated for assessing VGI quality based on a linguistic decision making approach so as to allow its feasible use for scientific purposes. VGI quality is represented by indicators at distinct levels of granularity which take into account the distinct components of the VGI items. The quality indicators represent both the extrinsic quality, depending on the characteristics and reputation of the sources of information; the intrinsic quality, depending on the distinct accuracy and precision of information; and, last but not least, the pragmatic quality, depending on the user needs and intended purposes. In order to assess the pragmatic quality of VGI items, a linguistic decision making approach is defined that allows users to rank and finally filter the VGI items based on the satisfaction of distinct criteria expressed by means of both linguistic terms, defining soft constraints on the distinct quality indicators, and linguistic aggregators, defining fuzzy operators which combine the satisfaction degrees of the soft constraints at distinct hierarchical levels to yield the final satisfaction of the VGI items. Finally, an example of quality assessment in a glaciological citizen science project is discussed.
    No preview · Article · Feb 2014 · Information Sciences
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    ABSTRACT: In questo studio abbiamo analizzato l'effetto della deposizione della polvere (dust) sahariana sulla crescita fitoplanctonica (i.e. l'ipotesi della fertilizzazione da dust) nel lago di Garda, un bacino oligotrofico con basse concentrazioni di nutrienti e di clorofilla (chl-a), unendo dati satellitari a misure in situ. Sono stati individuati due eventi di dust sahariano in corrispondenza del 28/07/2005 e del 9-10/10/2007 attraverso: (i) l'elaborazione dei dati SEVIRI (Spinning Enhanced Visible and InfraRed Imager), (ii) un aumento relativamente significativo di concentrazione di PM10 rispetto a quella di PM2.5 in corrispondenza di stazioni di misura in situ a sud e nord del Lago; e (iii) alti valori di spessore ottico atmosferico (AOT, Aerosol Optical Thickness) in concomitanza a bassi valori del coefficiente di Angstrom misurato dalla stazione delle rete AERONET di Ispra. A distanza di alcuni giorni dagli eventi, sono state registrate da immagini MERIS (Medium Resolution Imaging Spectrometer) un aumento delle concentrazioni di chl-a nel lago. Le immagini MERIS sono state processate attraverso l'algoritmo Case-2 Regional (C2R) della rete neurale VISATBEAM che ha prodotto valori comparabili con quelli misurati in situ (r=0.78). I risultati preliminari sembrano indicare un effetto sul lago di Garda in termini di aumento di chl-a in conseguenza degli eventi di dust sahariano del 28/07/2005 e del 9-10/10/2007. È importante precisare che al fine di avere o meno una conferma del collegamento fra la deposizione atmosferica e le dinamiche del fitoplancton nell'area di studio, è obbligatoria l'analisi di ulteriori eventi che saranno effettuati all’interno del progetto SINOPIAE.
    Full-text · Conference Paper · Nov 2013
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    ABSTRACT: In this study we investigated the effect of the deposition of Saharan dust on the phytoplankton growth (i.e. dust fertilization hypothesis) in Lake Garda, an oligotrophic basin with low nutrient and low chlorophyll-a (chl-a) concentration, by combining satellite data with in situ measurements. A Saharan dust event has been recognised on 28/07/2005 by: (i) SEVIRI (Spinning Enhanced Visible and InfraRed Imager) data processing, (ii) a significant increase of PM10 with respect to PM2.5 in a site southern the lake; and (iii) the high values of AOT (aerosol optical thickness) with corresponding low values of the Angstrom parameter measured by AERONET in Ispra. Few days later, an increase of chl-a in the lake was detected from MERIS (Medium Resolution Imaging Spectrometer). The images were processed with the Case-2 Regional (C2R) processor that provided values comparable to in situ measurements (r=0.78). Therefore, preliminary results seem to indicate a response of the Lake Garda in terms of increasing of chl-a as a consequence of the Saharan dust event recognised on 28/07/2005. Nevertheless, the analysis of further events is mandatory in order to have confirmation (or no), about the linkage between atmospheric deposition and phytoplankton dynamics in the study area.
    Full-text · Conference Paper · Sep 2013
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    ABSTRACT: In 2005, the EU made the strategic choice of developing a space-based programme, called Global Monitoring for Environment and Security (GMES). GMES is an independent Earth monitoring initiative led by the European Union and carried out in partnership with the Member States and the European Space Agency (ESA). Its primary objective is to provide information services that give access to accurate data and information in the field of the environment and security and are tailored to the needs of users. However, at the regional level, stakeholders are often not aware about the potential benefits of services Europe's GMES initiative can provide; yet Europe's ca. 350 regions represent a large reservoir of potential GMES users where GMES services can add value to existing services. Refining data, products and services from global GMES services in the various domains (i.e. land, marine, atmosphere, emergency response, security and climate change), GMES downstream services may be customised to individual user needs, many of which are to be found a the regional level. Within a number of regions, links between the different types of stakeholders have grown over the years. Often, individual actors have developed inter-regional links but their linkage is in most cases not formalised. When looking at the European scale, that overall awareness of GMES downstream opportunities is still very low with respect to the potential benefits regions could draw from a wider participation. However, being aware of the potential of GMES, of the important role they can play and of the need for exchanging experiences, pioneering Local and Regional Authorities (LRAs) intending to retrieve benefit from space technologies, including GMES, have now started to collaborate within structured networks, NEREUS being the most advanced example. The logically next step is that LRAs engage in a dialogue with service-industry and European decision-makers to maximize the benefits from these innovative tools which have significant impact on the economy, environment and the quality of life of the citizens To this aim since 2011 the system of Regional Contact Offices (RCOs) was promoted by the EU FP7 DORIS_Net (Downsteam Observatory organized by Regions Active in Space - Network, http://www.doris-net.eu/) project as the regional link to the services provided by the European GMES programme. Since then a first nucleus of 12 pilot European Regions were working together establishing 6 first RCOs around Europe. This paper will present RCOs network goals, achievements and perspectives as well as its planned actions devoted to improve quality of Space Technology products from one side, to promote awareness and use of them by potential end-users (and particularly LRAs), from the other side.
    No preview · Article · Apr 2013
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    ABSTRACT: This contribution proposes an approach to model regional landslide susceptibility, based on a supervised learning technique that mines fuzzy emerging patterns on a set of classified data. In our approach the training set contains positive and negative examples of areas, (i.e., slope units), affected or not affected by landslides. The fuzzy emerging patterns characterise the positive and the negative areas exploiting their ability to discriminate between the two classes. The approach consists first, in inducing a set of fuzzy rules, and then in reducing them by retaining those that identify fuzzy emerging patterns for the given training set. The fuzzy rules define the main characteristics of the slope units that are affected or not affected by landslides and are used to classify other slope units in the same region. The classification technique provides an estimate of the hesitation of the decision process, which is a measure of its ability to uniquely associate a slope unit to the susceptible or not susceptible class. In the paper we describe the approach and discuss the preliminary results.
    No preview · Article · Jan 2013
  • D. Bavera · C. De Michele · M. Pepe · A. Rampini
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    ABSTRACT: Snowmelt is an important component of the river discharge in mountain environments. In the past 40 years, the snowmelt dynamics has been mostly evaluated using degree‐day‐based models like the snowmelt runoff model (SRM). This model has no control on the volume of the melting snow, even if SRM includes as data input the snow‐covered area. This lack explains why the application of SRM may lead to inaccurate snowmelt volume estimations, even if the discharge volumes are accurately reproduced. Here we introduce in SRM the control on the melted snow volume and consider it in the determination of SRM parameters. The total snow volume, accumulated at the end of winter season, is evaluated by a snow water equivalent statistically based model, SWE‐SEM, and used as an estimate of the melting snow during the summer season. The benefit derived from the introduction of the control on the melting snow volume was investigated in the Mallero basin (northern Italy) for the 2003 and 2004 snow melting seasons. The analysis compares the model's results adopting different parameter sets, both considering and ignoring the control on the melting snow volume. Copyright © 2011 John Wiley & Sons, Ltd.
    No preview · Article · Oct 2012 · Hydrological Processes
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    ABSTRACT: The paper illustrates the potentials of geospatial data and services to access historical digital atlas for landscape analysis and territorial government. The experience of a historical geo-portal, the ‘Atl@nte dei Catasti Storici', in the management of geo-referenced and non-geo-referenced maps - ancient cadastral and topographic maps of Lombardy Region - can be considered a case study with common aspects to many European regions having an extensive cartographic heritage. The development of downstream web based services to integrate other data sources (current maps, satellite and UAV airborne photogrammetry, multi-spectral images and derived products) provides new scenarios for retrieving geospatial knowledge of territory, bridging the gap in supporting a sustainable management of the territory.
    Full-text · Conference Paper · Jun 2012
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    L Criscuolo · A Oggioni · M Pepe · P Carrara · A Rampini · F Zucca · R Seppi
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    ABSTRACT: CONTEXT OF THE RESEARCH This paper deals with the introduction of volunteer information in the workflow of data collection, monitoring of changes, and related alerts as regards the glacier environment realm in Italian Alps. Usually such topics are addressed within institutional frameworks by the use of tools and practices that merely belongs to science, as geosciences and environmental engineering. The revolutionary application features introduced by web 2.0, with the creation of collaborative networks and participative tools similar to social networks, has deeply changed the notion of geography itself and has brought a large number of neo-geographers to join the cartographic community. Such innovative tools, which are still debated by the international scientific community as regards their growing potentials as well as their inherent drawbacks (Goodchild 2007), are the base for our study for the improvement (by both qualitative and quantitative point of view) of the information regarding Alpine glaciers. The topic is of outstanding interest, since several studies recently are dealing with the glacier monitoring in a climate change and global warming perspective, in which small-medium glaciers represent optimal proxies of the Earth surface changes in energy and water budgets. Results of such studies are sometimes extraordinary also for the public and when efficiently disseminated they obtain a good impact on public awareness and their behaves (UNEP 2009). Hence there is a growing need of understanding the cryosphere and its phenomena, including Alpine glaciers; this understanding has as a basic element an intrinsically geographic element: the glacier. The glacier can be represented/modeled and measured in several different ways (qualitatively, quantitatively, as spatially and/or temporally distributed). Whatever the parameters used for glacier representation are, due to logistics and meteo-climatic issues, it is actual that the alpine glaciers are generally observed irregularly/occasionally and mainly by volunteers. As a consequence, there are some problems of scarcity of reports as connected to the volunteer character of contributions, to the number/complexity of measurements to be collected, to the lack of funding. Hence there is the need to: 1) improve the glaciological databases/collections (in terms of number of recordings and update frequencies); 2) enlarge the public engagement and the number of collaborators; 3) control the data quality while improving the awareness and knowledge of collaborators; 4) introduce such improvements with no additional charge. Neo-geography tools seems to be able to address the mentioned issues, as well as contributing to innovation in the field by two points of view: 1) as regards methods: the involvement of volunteers in an organized network could create a positive feedback context for improving the collection protocols in parallel with the understanding of phenomena observed, in a bottom-up approach, facilitating the sharing of data and knowledge; 2) as regards technology: advance application scenarios by adapting existing technologies to specific use-cases and analysis of criticisms. METHODS AND DEVELOPMENT The first step of the study was devoted to the analysis of requirements in the context of glaciological information improvement: subjects traditionally involved with an institutional mandate together with potential new collaborators have been considered to finally draw out the network of actors involved besides the possible solutions for their better engagement. In the Italian Alps the monitoring of glacier is performed by a network of different actors, who span from institutions of scientists or local authorities, to single volunteer operators (mainly hikers) who perform the annual observations in the field. Volunteers collect measurements following different protocols, often established on a local basis, usually determined mainly to address the mountain environment constraints and often without a comprehensive experimental design. This kind of present organization, even if worthwhile for both activity and continuity (some historical recordings of glacier fluctuations covers up to 100 years), suffers from some limitations that ask for further improvements and that can be summarized as follows: 1) Quantity, quality and spatial/temporal frequency/representation of reports, often too scarce to properly describe the ongoing changes, especially in the last decade; 2) Poor harmonization level of data formats and information contents on a national/international level; 3) Lack of enabling strategies to open and enlarge the community to several potential members, either as contributors, or as users of information Therefore the challenges to be addressed by the introduction of new approaches are to cope and exploit the traditional background of the volunteers, inserting it in a defined and well designed workflow, that can be shared at a regional/national level, that is operational and productive by the data collection point of view, but that it is also agreeable and rewarding for the contributors. After the objectives have been stated and the requirements of the application been analyzed, an architecture has been designed and implemented (figure 1). Figure 1 – Proposed architecture As regards the implementation choice, it has been focused on the selection of communication interfaces suitable for the specific aims and targets, while assessing the solutions in terms of pros and cons. Proposed tools are chosen from the Open and Free technological assets, to deal with the sharing data/knowledge and to avoid additional charges, taking advantage of the web 2.0 application features to collect and manage contributions coming from web users. The Ushahidi platform has been chosen as a first implementation framework to test the collection and visualization of information from volunteer contributions. This mapping application has proven to be easy of use, efficient in the report management together with open and dynamic access to updated maps and useful for the case study at hand. CONCLUSIONS Observation of glaciers is a key issue in global monitoring and climate change. In this framework the Italian alpine glaciers are generally observed irregularly (occasionally) and mainly by volunteers by the use of heterogeneous protocols, and without a comprehensive observation scheme. The resulting problems – mainly the scarcity of reports, connected both to the volunteer character of contributions, and to the complexity of measurements to be collected - have been analysed in terms of actors involved and requirements and addressed with actions expressly designed in a web architecture outline. The project is still at its early stage, anyway some first considerations can be drawn as response to the main criticism of the use case, i.e. that the neo-geography tool helped in: - Starting-up a reporting platform shared by different groups of local volunteers - Increasing number and frequency of reports - Monitoring of reporting by the administrator and evaluation processes performed by the volunteers involved - Rewarding of contributors and positive feedback for content improvement - Enlarging of the community - Disseminating and sharing data and knowledge to a wider public A SWOT analysis performed on these first outcomes has helped to reveal the good solutions and the potential constraints of the project, in order to boost the former and limit the latter. The experimental results give indications as regards future harmonizing actions as well as strategic operations in the field of glacier monitoring. ACKNOWLEDGEMENTS We are grateful to all the volunteers that annually survey Italian glaciers, and we thankfully acknowledge the excellent work behind the Ushahidi Open Source software. This research is carried out in the framework of a PhD programme of the University of Pavia, Dept. of Earth and Environmental Sciences and supported by CNR-IREA. REFERENCES GOODCHILD M (2007) - Citizens as Sensors: The World of Volunteered Geography, GeoJournal 69(4): 211-221. United Nations Environment Programme (UNEP) (2009), Global outlook for Ice & Snow, 2009, ISBN: 978-92-807-2799-9, UNEP Job No: DEW/0924/NA, http://www.unep.org/geo/geo_ice/
    Full-text · Conference Paper · Jun 2012
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    ABSTRACT: The ENVISAT mission with a suite of high performance sensors offers some opportunities for mapping snow cover at regional and catchment scale. The geometric resolution of MERIS data and the spectral resolution of AATSR data are suitable for these purposes. A new approach, developed in the framework of the GLASNOWMAP project (ESA-DUP2) for monitoring snow cover in Alpine regions, based on the combined use of MERIS and AATSR observations, and topographic information, is proposed. As MERIS spectral bands are not completely proper for the discrimination of snow from clouds - due to the lack of short wave infrared channels - a multisource classification scheme has been developed to combine the results obtained by the classification of MERIS data with the information on cloud distribution as derived from AATSR data; the integration is performed with the aid of snow elevation distribution as derived from the Digital Elevation Model. A supervised fuzzy statistical classifier (Wang 1990) has been chosen to perform classification of MERIS images, being particularly suited for the representation of land cover class mixture. The classifier bases estimates of the distribution of pixels in multispectral space on the concept of the probability measure of fuzzy events to produce an output of the proportions of individual components. A cloud normalized index has been defined to extract clouds from AATSR images previously registered and resampled on MERIS images. The results of MERIS and AATSR processing are integrated to produce a snow cover map masked over the cloud covered areas, taking into account also the elevation. The Alpine region is selected as test area to demonstrate the potential and limitations of the novel approach. In particular, the attention is focused on three regions of Northern Italy (Valle d'Aosta, Piemonte, Lombardia). The first results obtained by the application of this new method to Earth Observation data will be presented and analysed.
    Full-text · Article · May 2012
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    ABSTRACT: This study deals with the evaluation of accuracy benefits offered by a fuzzy classifier as compared to hard classifiers using satellite imagery for thematic mapping applications. When a crisp classifier approach is adopted to classify moderate resolution data, the presence of mixed coverage pixels implies that the final product will have errors, either of omission or commission, which are not avoidable and are solely due to the spatial resolution of the data. Theoretically, a soft classifier is not affected by such errors, and in principle can produce a classification that is more accurate than any hard classifier. In this study we use the Pareto boundary of optimal solutions as a quantitative method to compare the performance of a fuzzy statistical classifier to the one of two hard classifiers, and to determine the highest accuracy which could be achieved by hard classifiers. As an application, the method is applied to a case of snow mapping from Moderate-Resolution Imaging Spectroradiometer (MODIS) data on two alpine sites, validated with contemporaneous fine-resolution Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data. The results for this case study showed that the soft classifier not only outperformed the two crisp classifiers, but also yielded higher accuracy than the maximum theoretical accuracy of any crisp classifier on the study areas. While providing a general assessment framework for the performance of soft classifiers, the results obtained by this inter-comparison exercise showed that soft classifiers can be an effective solution to overcome errors which are intrinsic in the classification of coarse and moderate resolution data.
    No preview · Article · Dec 2010 · International Journal of Remote Sensing
  • S. Rossi · A. Rampini · S. Bocchi · M. Boschetti
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    ABSTRACT: This work presents a simple, cost-effective, and operational approach to monitor crop water requirements at the regional scale for water management and monitoring purposes. The recommended Food and Agricultural Organization of the United Nations methodology (FAO-56) calculates crop evapotranspiration using crop-specific coefficients (K(c)), which vary according to the crop type, health, and phenological stage. This approach, though widely applied for irrigation planning, cannot always match the appropriate crop coefficient with the actual crop phenological stage and health condition, especially in anomalous situations. Previous research demonstrated that crop coefficients and spectral vegetation indexes are correlated. Recent studies have used this relationship with high-resolution satellite data from different sensors to provide information to irrigation advisory services. However, high-resolution data are not feasible for an operational and routine monitoring of water consumption and needs. This paper tests the usefulness of time series of coarse resolution satellite data such as those collected by the moderate-resolution imaging spectroradiometer (MODIS) sensor, to monitor crop coefficients temporal and spatial variability and therefore crop water needs at the regional scale taking advantage of the peculiar characteristics offered by MODIS in terms of high temporal resolution and preprocessed products availability. The outlined methodology takes into account the actual growing stage of the crops and nearly real-time vegetation variations, overcoming some limitations of the traditional FAO approach while preserving the maximum operability. The analysis was carried out in the South Milan agricultural area on data referring to 2003 and 2004. The results agreed with those of other studies and proved to be able to account for the anomalous conditions of the summer in 2003. These results were then compared with those obtained using the traditional FAO crop coefficient curves built with data collected during field campaigns in the same years in rice fields. Constraints, limitations, and possible uses are discussed.
    No preview · Article · Apr 2010 · Journal of Irrigation and Drainage Engineering
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    J. Parajka · M. Pepe · A. Rampini · S. Rossi · G. Blöschl
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    ABSTRACT: The objective of this study is to propose and evaluate a method for snow cover mapping during clouds using the daily MODIS/Terra snow cover product. The proposed SNOWL approach is based on reclassifying pixels assigned as clouds to snow or land according to their relative position to the regional snow-line elevation. The accuracy of the SNOWL approach is evaluated over Austria, using daily snow depth measurements at 754 climate stations and daily MODIS/Terra images in the period July 2002–December 2005. The results indicate that the SNOWL method provides a robust snow cover mapping over the entire region even if the MODIS/Terra cloud cover is as large as 90%. Cloudiness is decreased from 60% (MODIS/Terra) to 10% (SNOWL) without hardly any change in mapping accuracy. Sensitivity analyses indicate that the estimation of the regional snow-line elevation is particularly sensitive to the misclassification of cirrus clouds as snow in the period between May and October.
    Full-text · Article · Feb 2010 · Journal of Hydrology
  • L. Díaz · M. Pepe · C. Granell · P. Carrara · A. Rampini
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    ABSTRACT: Available geospatial resources on the Web need to be accessed and easily exploited by scientists and decision makers. Organizations at multiple administrative levels are establishing interoperable infrastructures to improve accessibility, such as the Global Earth Observation System of Systems (GEOSS), and the Infrastructure for Spatial Information in Europe (INSPIRE). Also regarding hydrological resources management we encounter initiatives being carried out around the globe, to merge computer science with hydrology in order to improve the way experts work and make decisions. The current trend in geospatial applications and the key unit in the mentioned initiatives are Spatial Data Infrastructures (SDI) based on access to data and processes via web services following OGC (Open Geospatial Consortium) standards. Traditional SDIs support the most common and basic requirements of geospatial data users: Discovery, access, download and visualization of the data. Specialized users such as hydrological scientists, however, require more advanced services for processing data and observations using specialized models. There is a need to expose these models in SDI so scientific community can run and share them, as they do with data resources. In this framework we deployed two hydrological models where functionality is offered by a set of reusable web processing services on top of an SDI. These web services, designed with the criteria of modularity, can be reused to orchestrate distributed hydrological applications where shared remote data sources can be processed together with local data. In the framework of the GMES EC-funded project AWARE (A tool for monitoring and forecasting Available WAter REsource in mountain environments, www.aware-eu.info) we have built an application for predicting water discharge in the Alpine catchments based on a chain of these web geospatial services. The chain is provided to users within a Geoportal which is the entry point to an INSPIRE-based SDI where experts are guided to run one hydrological model.
    No preview · Article · Jan 2010
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    ABSTRACT: A geographic data base of burned areas in Italian National Parks was built using satellite images. Around five hundred ASTER and SPOT images were acquired for the period 2001-2005 and processed with photo-interpretation, multiple thresholds of spectral transforms (NBR and BAI) and Maximum Likelihood. In five years the area burned is more than 5000 ha (fire average size is 7.7 ha) and the most affected Parks are in Southern Italy. Satellite maps were compared with field observations from the Corpo Forestale dello Stato showing that remote sensing and ground based data provide complementary information. Burned area maps are delivered as layers of a Web Map Service (WMS) of a Spatial Data Infrastructure (SDI) INSPIRE compilant.
    Full-text · Article · Jun 2009 · European Journal of Remote Sensing
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    ABSTRACT: When looking for geodata in a Spatial Data Infrastructure (SDI), the user expresses precise selection conditions on the values of metadata in discovery services. In order to obtain a list of results, corresponding values of metadata must exactly match such conditions. This practice suffers from several drawbacks. First of all, with respect to the temporal characterization, available recommendations for metadata specification of the INSPIRE Directive are inadequate to satisfy the several semantics of the temporal conditions. To this aim, we propose to extend the metadata to enrich the description of geodata, with the possibility to indicate temporal metadata related to both the observations and the observed event as well as of specifying the temporal resolution of observations. Furthermore, we introduce a proposal to manage temporal series of geodata observed at different dates. In order to represent the uncertain and incomplete time knowledge on the available geodata, we allow the specification of imperfect temporal values which is not considered nor managed within INSPIRE. Last but not least, as far as the discovery service providing searching facilities on metadata catalogs, we propose to allow expressing flexible selection conditions, i.e. tolerant to under-satisfaction, so as to retrieve geodata in decreasing order of relevance to the user needs, as it usually occurs on the Web when using search engines. This contribution discusses the above limitations and the related solutions, expressed in terms of formal and operational methods taking into account imperfect temporal metadata values and flexible search conditions. Proposals will be illustrated with examples taken from an already existing European SDI.
    Full-text · Article · Jan 2009
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    ABSTRACT: In this paper we analyze the limitations of current recommendations of the INSPIRE (Infrastructure for Spatial Information in Europe) Directive as far as the temporal metadata definition for discovery purposes, and propose its extension so as to allow the representation and management of imperfect spatio- temporal metadata. We propose to extend the metadata in order to cope with the requirements of both metadata producers, who often are unable to specify precise values, and users who submit queries to catalog services for discovering interesting data, who may express soft selection conditions on metadata values. The proposal is illustrated and explained through an example taken from an active Spatial Data Infrastructure (SDI).
    Full-text · Conference Paper · Jan 2009
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    ABSTRACT: Current efforts for simulating or forecasting snowmelt are time-consuming and laborious; the AWARE project (A tool for monitoring and forecasting Available WAter REsource in mountain environments) has been motivated by the urgent need to facilitate the prediction of medium-term flows from snowmelt for an effective and sustainable water resources management. Its main goal is to provide innovative tools for monitoring and predicting water availability and distribution in drainage basins where snowmelt is a major component of the annual water balance. The particular objective of the effort reported here is to compare results obtained from the MODIS sensor on NASA Terra and Aqua satellite and next generation sensors AATSR and MERIS on board ESA Envisat satellite. The vehicle for this comparison is the AWARE Geoportal (http://www.aware- eu.info/eng/home.htm) which is a WWW implementation of the Snowmelt Runoff Model (SRM). The river basin chosen for analysis is the Upper Rio Grande of North America. The time period for analysis encompasses the Water Years 2005, 2006, and 2007 (October 2004 - September 2007). The reason for this is to ensure that data from all three sensors are available for use and to investigate variable climate conditions. A successful comparison between the various sensors will help demonstrate that the AWARE approach will facilitate future processing of several years' worth of snow cover data from a variety of sensors that covers large extremes in climate variability. This will allow greater success in developing forecasts and understanding of longer term climate change impacts.
    No preview · Article · Nov 2008