Search results for "ACTUAL EVAPOTRANSPIRATION"
showing 10 items of 21 documents
Analysis of energy fluxes estimations over Italy using time-differencing models based on thermal remote sensing data
2012
Large area estimations of land surface fluxes can be a useful operational tool for up-scaling local measurements and can serve as an upper-boundary condition for higher spatial resolution applications. Given hourly measurements of radiometric surface temperature from a geostationary satellite, it is possible to derive the partitioning of energy fluxes based on the influence of the evapotranspiration process on morning surface temperature rise. In this work, the Atmosphere-Land Exchange Inverse (ALEXI) model and the Dual Temperature Difference (DTD) approach were applied in order to relate the sensible heat flux to time-differential remote observations of surface temperature obtained from Me…
Evaluating actual evapotranspiration by means of multi-platform remote sensing data: A case study in Sicily
2007
During the last two decades, the scientific community developed detailed mathematical models for simulating land surface energy fluxes and crop evapotranspiration rates by means of an energy balance approach. These models can be applied in large areas and with a spatial distributed approach using surface brightness temperature and some ancillary data retrieved from satellite/airborne remote sensed imagery. In this paper a district scale application, in combination with multispectral satellite and airborne data has been carried out to test the potential of two different energy balance models to estimate evapotranspiration fluxes from a set of typical Mediterranean crops (wine, olive, citrus)…
Assessing actual evapotranspiration via surface energy balance aiming to optimize water and energy consumption in large scale pressurized irrigation …
2017
Satellite imagery provides a dependable basis for computational models that aimed to determine actual evapotranspiration (ET) by surface energy balance. Satellite-based models enables quantifying ET over large areas for a wide range of applications, such as monitoring water distribution, managing irrigation and assessing irrigation systems’ performance. With the aim to evaluate the energy and water consumption of a large scale on-turn pressurized irrigation system in the district of Aguas Nuevas, Albacete, Spain, the satellite-based image-processing model SEBAL was used for calculating actual ET. The model has been applied to quantify instantaneous, daily, and seasonal actual ET over high- …
A critical analysis of three remote sensing-based actual evapotranspiration assessment methods over sparse crops agricultural areas
2010
During last two decades the increasing availability of remotely sensed acquisitions in the thermal infrared part of the spectrum has encouraged hydrologist community to develop models and methodologies based on these kind of data. The aim of this paper is to compare three methods developed to assess the actual evapotranspiration spatial distribution by means of remote sensing data. The comparison was focused on the differences between the "single" (SEBAL) and "two" source (TSEB) surface energy balance approaches and the S-SEBI semi-empirical method. The first assumes a semiempirical internal calibration for the sensible heat flux assessment; the second uses a physically based approach in or…
Assessing opportunities for water savings in large-scale pressurized irrigation systems using actual evapotranspiration retrieved by surface energy b…
Remote sensing allows the observation of large land stretches and the acquisition of worthwhile information that can be used efficaciously in agro-hydrologic systems. Satellite imagery associated to computational models provide a reliable resource in estimating evapotranspiration (ET) fluxes based on surface energy balance. On irrigated crops, quantifying the spatial distribution of actual ET enables a broad range of applications such as irrigation management, monitoring water distribution, assessing crop water status and irrigation system performance. The general objective of the research was to propose a methodology to estimate ET by using Landsat Thematic Mapper (TM) images and surface e…
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…
Evaluation of the MOD16A2 evapotranspiration product in an agricultural area of Argentina, the Pampas region
2021
The Pampas Region is a big plain of approximately 520,000 km2 in Argentina. It is essential to estimate evapotranspiration (ET) in this region since the primary productivity is directly linked to water availability. Information provided by satellite missions allows monitoring the spatial and temporal variability of ET. In the current study, we evaluated the version 006 of MOD16A2 product (MOD16A2.006) of Potential Evapotranspiration (ETp) and Actual Evapotranspiration (ETa) in Argentinian Pampas Region (APR). MOD16A2.006 product was compared with Crop Evapotranspiration (ETc), calculated with local measurements from the Oficina de Riesgo Agropecuario (ORA), and Crop Coefficient (Kc) data (f…