Search results for "SEBAL"
showing 10 items of 22 documents
Assessing the performance of a large-scale irrigation system by estimations of actual evapotranspiration obtained by Landsat satellite images resampl…
2019
Abstract Remote sensing techniques allow monitoring the Earth surface and acquiring worthwhile information that can be used efficiently in agro-hydrological systems. Satellite images associated to computational models represent reliable resources to estimate actual evapotranspiration fluxes, ETa, based on surface energy balance. The knowledge of ETa and its spatial distribution is crucial for a broad range of applications at different scales, from fields to large irrigation districts. In single plots and/or in irrigation districts, linking water volumes delivered to the plots with the estimations of remote sensed ETa can have a great potential to develop new cost-effective indicators of irr…
Comparison between energy balance and mass balance models for actual evapotranspiration assessment
2009
The assessment of the water needs for a specific crop has a fundamental importance in the management of water resources. The application of empirical models able to retrieve estimates of the actual evapotranspiration (ETa) to assess the need for water could give a valid tool for the planning of water supply, avoiding unnecessary water losses. In this context, two independent models for estimating actual evapotranspiration were compared. The first model is based on an energy balance and uses remotely sensed data and ancillary data from weather stations to assess the ETa. The second model also uses remotely sensed data and climatic data on a daily basis from a weather network. Field measureme…
Estimation of actual evapotranspiration of Mediterranean perennial crops by means of remote-sensing based surface energy balance models
2009
Abstract. Actual evapotranspiration from typical Mediterranean crops has been assessed in a Sicilian study area by using surface energy balance (SEB) and soil-water balance models. Both modelling approaches use remotely sensed data to estimate evapotranspiration fluxes in a spatially distributed way. The first approach exploits visible (VIS), near-infrared (NIR) and thermal (TIR) observations to solve the surface energy balance equation whereas the soil-water balance model uses only VIS-NIR data to detect the spatial variability of crop parameters. Considering that the study area is characterized by typical spatially sparse Mediterranean vegetation, i.e. olive, citrus and vineyards, alterna…
Effect of morphology on remote sensing-based evapotranspiration assessment at basin scale
2011
Assessing actual evapotranspiration in irrigation districts using Landsat TM images and SEBAL model: Potential uses for irrigation monitoring
2018
Satellite imagery allows the observation of large land stretches and the acquisition of worthwhile information that can be used efficaciously in agro-hydrologic systems. On the other hand, remotely sensed data coupled with energy balance models represent reliable tools to estimate actual evapotranspiration (ET). Objective of the research was to propose a methodology to estimate ET by using Landsat TM images and surface energy balance, thus allowing the monitoring of current irrigation practices and/or possible vegetation stress. The proposed methodology was applied in an irrigation district managed by “Consorzio di Bonifica Agrigento 3”, Castelvetrano, Sicily (Italy), in which water is dist…
W.G. Sebald: Amistat i Escriptura
2022
El nostre propòsit, aquí, és el d’articular una idea de po- ètica de l’amistat en l’obra de Winfried Georg Sebald. L’es- criptor alemany, tal vegada el més significatiu entre el final del segle xx i el començament del nou mil·lenni, ha captat l’atenció internacional per una llarga sèrie de temes que re- corren la seva obra: l’interès per la memòria històrica, amb una referència específica al tema de la Xoà i a la recons- trucció del diàleg entre el poble jueu i el poble alemany, sense oblidar temes més específicament «poetològics» com la relació entre el llenguatge i la imatge o la utilització d’es- tratègies intertextuals. Seguint l’estela de les reflexions de Walter Benjamin, Sebald també…
Fuoco pallido. W.G. Sebald: l'arte della trasformazione
2019
Questo libro nasce dal bisogno, comune a molti lettori di W.G. Sebald, di ritor-nare circostanziatamente su alcuni passi della sua opera poetica e critica, per riprendere a seguirne i percorsi, per scorgere ulteriori strati, ulteriori tempi che vi sono custoditi. Si sarebbe forse tentati per questo aspetto di rinviare addirit- tura alle “idee estetiche” kantiane, a quelle rappresentazioni dell’immaginazio- ne che danno molto da pensare, senza che alcun concetto determinato sia ad esse adeguato, se non fosse per il netto tenore cosale che in generale domina tali passi, per l’ostinazione con cui le venature materiali vi vengono messe in risalto, e reiterate, e disposte come pietre segnaletich…
Assessing daily actual evapotranspiration through energy balance: an experiment to evaluate the selfpreservation hypothesis with acquisition time
2013
An operational use of the actual evapotranspiration estimates requires the integration from instantaneous to daily values. This can commonly be achieved under the hypothesis of daytime self-preservation of the evaporative fraction. In this study, it has been evaluated the effect of this assumption on the assessment of daily evapotranspiration from proximity sensing images acquired at hourly intervals over a homogeneous olive groove. Results have been validated by comparison with observations made by a micrometeorological (EC-flux tower) and an eco-physiological (sap flux) sensor. SEBAL model has been applied to thermal and multispectral images acquired during a clear day on August 2009 trou…
Bild unserer irren Anwesenheit/auf der Oberfläche der Erde. L’immagine come storia naturale del presente nella poetica diW. G. Sebald
2017
The poem Nach der Natur by W. G. Sebald, real germinal place of its author’s subsequent literary production, is a salient moment of confrontation for today's philosophical gaze; our historical time and our own humanity are configured as “natural history” (Benjamin), in a compositional game in which the present time acquires the character of a timeless distance projecting it on the background of a mournful nature, entrusting to the roughness of the poetic material and to its conceptual weaving the task of an unprecedented presentification of some layers of reality of rare density.