Search results for " idrologia"

Creazione di un database per l’applicazione di modelli empirici di analisi di dissesto idrogeologico da precipitazione nel territorio Siciliano.

2013

La previsione di fenomeni di dissesto idrogeologico è uno strumento essenziale di supporto alle decisioni per una corretta pianificazione del territorio. Tra tali fenomeni quelli franosi possono assumere dimensioni particolarmente rilevanti. Il fattore scatenante più ricorrente nella gran parte dei casi di frane documentate e’ costituito dalle precipitazioni. La letteratura scientifica propone diverse metodologie di analisi volte a fornire strumenti di pre-allarme in vista di un evento meteorico critico o di derivazione di mappe tematiche delle aree a maggiore suscettibilità franosa. I modelli empirici per la derivazione di soglie pluviometriche critiche di innesco risultano tra i più utili…

Statistica degli estremi idrologici in Sicilia

2009

Il carattere torrentizio di tutti i più importanti corsi d'acqua siciliani ha da sempre determinato esondazioni delle onde di piena e conseguenti allagamenti delle aree limitrofe provocando danni rilevanti. La valutazione delle piene e del rischio idrologico ad esse connesso può essere condotta secondo un approccio di tipo probabilistico attraverso il quale si determini una relazione tra la portata di piena di assegnata frequenza probabile ed il tempo di ritorno. In questo articolo sono richiamate le leggi di distribuzione di probabilità solitamente usate in idrologia, con particolare riferimento all'analisi probabilistica del valore massimo annuale della portata al colmo di piena e dell'al…

Produttività dell’ulivo e dinamiche di umidità del suolo

2010

Modeling the shrub and juniper encroachment in the western north America grasslands with a Cellular Automata model

2013

Development of an early warning system to predict sewer overflow

Flash flooding in our city is still a fairly common phenomenon.Unfortunately, the development of a flash flood forecasting system in urban areas is not a simple and unambiguous procedure.While attending the PhD course in Civil and Environmental Engineering, research activity has been given to realize an urban overflowing prediction system that was best as possible suited to the drainage network of the city of Palermo. With the support of radar data and hybrid hydraulic model for drainage network has been possible to demonstrate the effectiveness of this instrument, while the reduction of residual flood risk has been supported by modern resilience measures.

On the use of innovative post-event data for reducing uncertainty in calibrating flood propagation models

2013

Hydraulic models for flood propagation description are an essential tool in many fields and are used, for example, for flood hazard and risk assessments, evaluation of flood control measures, etc. However, the calibration of these models is still underdeveloped in contrast to other models like e.g. hydrological models essentially for lacking of specific data, because extreme flood events occur rarely and very rarely are monitored. Very often calibration data, when available, consist of water depths measure in some scattered points. For an inundation event occurred on November 2011 in Sicily, new sources of data were available due to the availability of many videos recorded by ‘common’ peopl…

Propagation of precipitation measurement biases into the hydraulic modelling of urban drainage systems: a case study

2021

Precipitation is the primary source of freshwater, while it can have great socio-economical impacts associated with extreme weather events such as floods and droughts. Good quality hydro-meteorological data is an essential condition not only for climate analysis but also for warning systems, hydraulic structures design, risk assessment, etc. In fact, precipitation is one of the most intensively used variables in hydrological modelling and its measurement accuracy is of foremost importance (Peterson et al., 1998). Accurate and timely knowledge of precipitation characteristics at urban and natural basins scales is essential for understanding how different catchment hydrological systems operat…

Effects of climate and land use changes on runoff extremes

2017

The analysis of the hydrological changes and their interacting triggering factors are objectives defined within the Panta Rhei decade 2013-2022. Climate change and urbanization are among the most recurrent causes for hydrological changes at the global level. This work proposes a modeling framework for the analysis of the alterations in the watershed hydrological response and, more specifically, in runoff extremes, induced by such perturbations. A weather generator and a cellular automata land-use change model are used to generate hypothetical scenarios accounting for relevant trends at the global level. Such scenarios are successively considered to force a physically-based and spatial-distr…

Detecting hydrological changes through conceptual model

2015

Natural changes and human modifications in hydrological systems coevolve and interact in a coupled and interlinked way. If, on one hand, climatic changes are stochastic, non-steady, and affect the hydrological systems, on the other hand, human-induced changes due to over-exploitation of soils and water resources modifies the natural landscape, water fluxes and its partitioning. Indeed, the traditional assumption of static systems in hydrological analysis, which has been adopted for long time, fails whenever transient climatic conditions and/or land use changes occur. Time series analysis is a way to explore environmental changes together with societal changes; unfortunately, the not disting…

Modelling flows duration curves in Mediterranean river basins through an ecohydrological approach

2011

The flow duration curve, representing the relationship between magnitude and frequency of streamflows in a basin, provides an important synthesis of the relevant hydrological processes occurring at the basin scale. It is typically obtained from field observations and, since most of the geographical areas of the world still lack suitable streamflow observations, its reconstruction in ungauged river basins is certainly an open and relevant issue in the hydrological literature. Different theoretical approaches have been developed in recent years, and in particular, a novel ecohydrological framework has provided considerable results. The aim of this study is to test with field data, a recent an…