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The paper deals with the problem of answering users queries searching for convenient paths to sequentially visit a number or relevant retrieved territorial resources and services. An exemplification is described by illustrating a Smart cOmmunity-based Geographic infoRmation rEtrievAl SysTem (SO-GREAT) that collects and manages heterogeneous georeferenced data about both authoritative resources and services offered by volunteers. Paths through relevant retrieved resources are automatically generated and ranked based by considering personal priorities

Historians and historical climatologists have long pointed to an increased flood frequency in Central Europe in the mid and late 19th century. However, the causes have remained unclear. Here, we investigate the changes in flood frequency in Switzerland based on long time series of discharge and lake levels, of precipitation and weather types, and based on climate model simulations, focusing on the warm season. Annual series of peak discharge or maximum lake level, in agreement with previous studies, display increased frequency of floods in the mid 19th century and decreased frequency after the Second World War. Annual series of warm-season mean precipitation and high percentiles of 3-day precipitation totals (partly) reflect these changes. A daily weather type classification since 1763 is used to construct flood probability indices for the catchments of the Rhine in Basel and the outflow of Lake Lugano, Ponte Tresa. The indices indicate an increased frequency of flood-prone weather types in the mid 19th century and a decreased frequency in the post-war period, consistent with a climate reconstruction that shows increased (decreased) cyclonic flow over Western Europe in the former (latter) period. To assess the driving factors of the detected circulation changes, we analyse weather types and precipitation in a large ensemble of climate model simulations forced with observed sea-surface temperatures. In the simulations, we do not find an increase in flood-prone weather types in the Rhine catchment in the 19th century, but a decrease in the post-war period related to the sea-surface temperature anomalies.

In this paper, we introduce an original approach that exploits timestamped geo-tagged messages posted by \emph{Twitter} users through their smartphones when they travel to trace their trips. A clustering approach is applied to group similar trips to identify tours, and an interoperable framework is used to share the popular tours on the Web, in order to analyse them in relation with local geo-located territorial resources. Tools developed to reconstruct and mine the tours of tourists within a region are described, which identify, track, and group the tourists' trips through a knowledge-based approach, exploiting timestamped geo-tagged information associated with \emph{Twitter} messages sent by tourists while travelling. The collected tracks are managed and shared on the Web in compliance with OGC standards so as to be able to analyze the characteristic of localities visited by the tourists by spatial overlaying with other open geo-spatial data, such as maps of Points Of Interest (POIs) of distinct type. The result is a novel Interoperable framework, based on web-service technology.

The paper describes a clustering approach using distinct similarity measures applied to group trajectories derived by tracking users of mobile social data exploiting the geotags of their posts.

U radu se izvještava o studiju slučaja o planiranju i razvoju Platforme utemeljene na informacijama i znanju (Information and Knowledge-based Platform – IKP), čiju jezgru čini Infrastruktura geoprostornih podataka (Geospatial Data Infrastructure – GDI). Platforma je namijenjena podržavanju poljoprivrednog sektora u Lombardiji u Italiji. Glavna novina u ovom radu odnosi se na upravljanje skupovima prostornih podataka i vremenskih serija iz heterogenih izvora podataka. Tijela vlasti omogućuju pristup bazama podataka poljoprivrednih deklaracija, agronomskih katastarskih karata i meteoroloških podataka u stvarnom vremenu. Istraživačke ustanove proizvode skupove geoprostornih podataka i vremenske serije obradom snimaka dobivenih daljinskim istraživanjima, i to multispektralnih optičkih i slika SAR-a (Synthetic Aperture Radar). Konačno, građani i dobrovoljci, kao što su farmeri i poljoprivredni radnici na terenu izvješćuju o opažanjima in situ upotrebom pametnih tehnologija. Tehnološki okvir predstavlja novi pristup upravljanju geoprostornim skupovima podataka i vremenskim serijama heterogenih izvora te integriranoj obradi dobrovoljnih geoinformacija (Volunteered Geographic Information – VGI) u okviru infrastrukture geoprostornih podataka. Rad opisuje prototip IKP-a koji omogućuje ostvarljivo rješenje koje se može primijeniti pri prijenosu tehnologije u stvarnoj provedbi IKP-a u državnim i regionalnim poljoprivrednim sektorima., The paper reports a case study on the design and development of an Information and Knowledge-based Platform (IKP), whose core is a Geospatial Data Infrastructure (GDI). The IKP aims to support the agriculture sector in the Lombardy region of Italy. The main novelty of the present work is related primarily to the management of geospatial data sets and time series from heterogeneous data sources. Authoritative bodies provide access to databases of agricultural declarations, agronomic cadastral maps, and real-time meteorological data. Research institutions produce geospatial data sets and time series by processing and analysing remote sensing images, both multispectral optical and SAR (Synthetic Aperture Radar) images. Finally, citizens and volunteers, such as farmers, or on-field operators belonging to agricultural associations, report in situ observations using smart technologies. The technological framework presents a novel approach related both to the workflow management of geospatial data sets and time series of heterogeneous sources, and the integrated processing of Volunteered Geographic Information (VGI) within a GDI. The paper describes a prototype IKP, which provides a feasible solution that can be used for technology transfer in the real implementation of the IKP in regional and national agriculture sectors.

Historians and historical climatologists have long pointed to an increased flood frequency in central Europe in the mid- and late 19th century. However, the causes have remained unclear. Here, we investigate the changes in flood frequency in Switzerland based on long time series of discharge and lake levels, precipitation, and weather types and based on climate model simulations, focusing on the warm season. Annual series of peak discharge or maximum lake level, in agreement with previous studies, display increased frequency of floods in the mid-19th century and decreased frequency after the Second World War. Annual series of warm-season mean precipitation and high percentiles of 3 d precipitation totals (partly) reflect these changes. A daily weather type classification since 1763 is used to construct flood probability indices for the catchments of the Rhine in Basel and the outflow of Lake Lugano, Ponte Tresa. The indices indicate an increased frequency of flood-prone weather types in the mid-19th century and a decreased frequency in the post-war period, consistent with a climate reconstruction that shows increased (decreased) cyclonic flow over western Europe in the former (latter) period. To assess the driving factors of the detected circulation changes, we analyze weather types and precipitation in a large ensemble of atmospheric model simulations driven with observed sea-surface temperatures. In the simulations, we do not find an increase in flood-prone weather types in the Rhine catchment in the 19th century but a decrease in the post-war period that could have been related to sea-surface temperature anomalies.

About 54% of world population nowadays lives in urban areas and this percentage is expected to increase up to 66% by 2050. Therefore, it is crucial to manage this social and cultural change by collecting, integrating and sharing reliable and open spatial information concerning the urban environments where we leave in. The present availability of huge archives of synthetic aperture radar (SAR) data collected since 1992 by ESA, in conjunction with the available Earth-Observation (EO) optical data, represents a unique possibility to derive valuable information for the understanding of the ongoing urban processes. In this framework, the three-year project financed by the Italian Ministry of Instruction, Research and University, entitled "URBAN GEOmatics for bulk information generation, data assessment and technology awareness" may play a role for the assessment and the development of new replicable methodologies for the study of soil consumption and mobility in urban zones. The paper aims to present some preliminary results achieved during the project, clarifying how the new emerging technologies for managing big EO data are proficient for the investigation of urban processes.