Search

Your search keyword '"Gallego-Elvira, Belen"' showing total 11 results
Start Over Author "Gallego-Elvira, Belen" Publication Year Range Last 10 years
11 results on '"Gallego-Elvira, Belen"'

5. Evaluation of regional-scale soil moisture-surface flux dynamics in Earth system models based on satellite observations of land surface temperature

Author

Gallego-Elvira, Belen, Taylor, Christopher M., Harris, Phil P., Ghent, Darren, Gallego-Elvira, Belen, Taylor, Christopher M., Harris, Phil P., and Ghent, Darren

Abstract

There is a lack of high‐quality global observations to evaluate soil drying impacts on surface fluxes in Earth system models (ESMs). Here we use a novel diagnostic based on the observed warming of the land relative to the atmosphere during dry spells (relative warming rate, RWR) to assess ESMs. The ESMs show that RWR is well correlated with changes in the partition of surface energy between sensible and latent heat across dry spells. Therefore, comparisons between observed and simulated RWR reveal where models are unable to capture a realistic soil moisture‐heat flux relationship. The results show that in general, models simulate dry spell ET dynamics well in arid zones while decreases in evaporative fraction appear excessive in some models in continental climate zones. Our approach can help guide land model development in aspects that are key in simulating extreme events like heat waves.

Published
2019

7. Monitoring evapotranspiration from remote sensing data for groundwater resources evaluation

Author

Olioso, Albert, Allies, Aubin, Ollivier, Chloé, Velluet, Cécile, Leblanc, Marc, Demarty, Jérôme, Boulet, Gérard, Bahir, Malik, GALLEGO-ELVIRA, Belen, Mira, M., Marloie, Olivier, Martin-StPaul, Nicolas, Tweed, S., Cappelaere, B., Huard, Frederic, Chauvelon, P., Boutron, O., Chalikakis, Konstantinos, Garrigues, Sébastien, Mazzilli, Naomi, Weiss, Marie, Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Hydrosciences Montpellier (HSM), Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut Parisien de Chimie Moléculaire (IPCM), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Centre Hospitalier Bretagne Atlantique, Centre d'études spatiales de la biosphère (CESBIO), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), UE Agroclim (UE AGROCLIM), Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS), Institut de Recherche Dupuy de Lôme (IRDL), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Université de Brest (UBO)-Université de Bretagne Sud (UBS), Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre hospitalier Bretagne Atlantique (Morbihan) (CHBA), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement et la société-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Université Jean Monnet [Saint-Étienne] (UJM), Agroclim (AGROCLIM), Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Météo France-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Météo France, Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM), Ecologie des Forêts Méditerranéennes (URFM), Université Blaise Pascal - Clermont-Ferrand 2 (UBP), Tour du Valat, Research Institute for the conservation of Mediterranean Wetlands, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), and ProdInra, Migration

Subjects
[SDV] Life Sciences [q-bio], [SDE] Environmental Sciences, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience; Evapotranspiration (ET) is a fundamental variable of the hydrological cycle which plays a major role on surface water balance and surface energy balance. At local scale ET can be estimated from detailed ground observations (eddy covariance towers), but these measurements are only representative of very limited homogeneous area. When regional information is required, e.g. for monitoring ground water resources, the flux tower measurements cannot be used directly and estimation of ET often relies on estimation from meteorological data through potential evapotranspiration formulas. At regional scale remote sensing provides spatially distributed information for mapping and monitoring ET, but this information is still rarely used for ground water assessment. Indeed, remote sensing estimation of ET suffers several drawbacks. In particular, remote sensing information by itself cannot provide a continuous monitoring of ET because of the presence of clouds and the revisit period of the sensor. Another difficulty originates in the lack of exhaustive evaluation of remote sensed ET since accurate ground measurements are scarce and representative of a limited number of homogeneous areas. This has also for consequence that a large number of methodologies to derive ET were developed with no real possibility of a consistent evaluation. We have developed the EVASPA (EVapotranspiration Assessment from SPAce) tool to monitor ET on a daily basis, together with an evaluation of the associated uncertainties, from remote sensing data in the thermal and the solar domains (Gallego Elvira et al. 2013). This tool combines the estimation of ET from various models and various sources of data, including MODIS sensors, LANDSAT-borne sensors and meteorological information. EVASPA was applied to estimate evapotranspiration over several areas in the products such as MOD16 or analysis of atmospheric-hydrological modeling such as the operational Safran-Isba-Modcou application). The results highlight the potential use of the retrieved ET for calibrating groundwater models (e.g. for estimating aquifer parameters…) or evaluating model inputs (e.g. determination of effective rainfall, identification of irrigated areas…). We also evaluated the impact of the uncertainties in the estimation of ET in the monitoring of ground water. We showed that the main sources of ET uncertainty were related to the uncertainties in incident radiations and surface temperature together with the diversity of ET models. When forced in ground water models, the uncertainties in ET had an impact almost equivalent to the impact of uncertainties in rain inputs. South of France to help in monitoring the water budget of different hydrosystems: superficial aquifer in the Rhône river delta (Camargue), karstic aquifer of the Fontaine de Vaucluse spring system and alluvial aquifer in Limagne with increasing water withdrawing for irrigation. The method was first evaluated against flux tower measurements of evapotranspiration (RMSE between 0.5 and 1 mm/day depending on the ecosystems). When integrated over watershed, ET retrievals were also compared to indirect estimates of evapotranspiration from either water balance and stream flow monitoring or other modelling approaches for time period of more than a decade (these include remote sensing operational

Published
2017

8. Evaluation and Aggregation Properties of Thermal Infra-Red-Based Evapotranspiration Algorithms from 100 m to the km Scale over a Semi-Arid Irrigated Agricultural Area

Author

Bahir, Malik, Boulet, Gilles, Olioso, Albert, Rivalland, Vincent, Gallego-Elvira, Belen, Mira, Maria, Rodriguez, Julio-Cesar, Jarlan, Lionel, Merlin, Olivier, Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre d'études spatiales de la biosphère (CESBIO), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées, Centre National d'Études Spatiales [Toulouse] (CNES), Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD [France-Ouest]), Université Toulouse III - Paul Sabatier (UT3), Centre for Ecology & Hydrology, Lancaster Environment Centre, Lancaster University-Lancaster University, Department of Geography, University of Liverpool, Departamento de Agricultura y Ganadería, Universidad de Sonora (USON), Thermal InfraRed SpaTial System(THIRSTY), projects 'EVAluation de l’EVApotranspiration issue de l’Infra Rouge Thermique' (EVA2IRT) and 'EVApotranspiration from SPAce V3' (EVASPA3), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Groupe d'étude de l'atmosphère météorologique (CNRM-GAME), Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), and Université de Toulouse (UT)

Subjects
[SDV.SA]Life Sciences [q-bio]/Agricultural sciences, [SDE.IE]Environmental Sciences/Environmental Engineering, [SDE.MCG]Environmental Sciences/Global Changes, scaling, catégorie statistique, température de surface, évapotranspiration, energy balance, Agricultural sciences, Thermal Infra-Red, effet d'échelle, bilan énergétique, Meteorology and Climatology, Agriculture and Soil Science, zone agricole, lcsh:Q, [SDV.EE.BIO]Life Sciences [q-bio]/Ecology, environment/Bioclimatology, lcsh:Science, Space Sciences, ComputingMilieux_MISCELLANEOUS, Sciences agricoles, infrarouge thermique, végétation semi aride
Abstract

Evapotranspiration (ET) estimates are particularly needed for monitoring the available water of arid lands. Remote sensing data offer the ideal spatial and temporal coverage needed by irrigation water management institutions to deal with increasing pressure on available water. Low spatial resolution (LR) products present strong advantages. They cover larger zones and are acquired more frequently than high spatial resolution (HR) products. Current sensors such as Moderate-Resolution Imaging Spectroradiometer (MODIS) offer a long record history. However, validation of ET products at LR remains a difficult task. In this context, the objective of this study is to evaluate scaling properties of ET fluxes obtained at high and low resolution by two commonly used Energy Balance models, the Surface Energy Balance System (SEBS) and the Two-Source Energy Balance model (TSEB). Both are forced by local meteorological observations and remote sensing data in Visible, Near Infra-Red and Thermal Infra-Red spectral domains. Remotely sensed data stem from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and MODIS sensors, respectively, resampled at 100 m and 1000 m resolutions. The study zone is a square area of 4 by 4 km(2) located in a semi-arid irrigated agricultural zone in the northwest of Mexico. Wheat is the dominant crop, followed by maize and vegetables. The HR ASTER dataset includes seven dates between the 30 December 2007 and 13 May 2008 and the LR MODIS products were retrieved for the same overpasses. ET retrievals from HR ASTER products provided reference ET maps at LR once linearly aggregated at the km scale. The quality of this retrieval was assessed using eddy covariance data at seven locations within the 4 by 4 km(2) square. To investigate the impact of input aggregation, we first compared to the reference dataset all fluxes obtained by running TSEB and SEBS models using ASTER reflectances and radiances previously aggregated at the km scale. Second, we compared to the same reference dataset all fluxes obtained with SEBS and TSEB models using MODIS data. LR fluxes obtained by both models driven by aggregated ASTER input data compared well with the reference simulations and illustrated the relatively good accuracy achieved using aggregated inputs (relative bias of about 3.5% for SEBS and decreased to less than 1% for TSEB). Results also showed that MODIS ET estimates compared well with the reference simulation (relative bias was down to about 2% for SEBS and 3% for TSEB). Discrepancies were mainly related to fraction cover mapping for TSEB and to surface roughness length mapping for SEBS. This was consistent with the sensitivity analysis of those parameters previously published. To improve accuracy from LR estimates obtained using the 1 km surface temperature product provided by MODIS, we tested three statistical and one deterministic aggregation rules for the most sensible input parameter, the surface roughness length. The harmonic and geometric averages appeared to be the most accurate.

Published
2017
Full Text
View/download PDF

9. EVASPA : EVapotranspiration Assessment from SPAce

Author

Olioso, Albert, Gallego-Elvira, Belen, Bahir, Malik, Boulet, Gilles, Weiss, Marie, Mira Sarrio, Maria, Reyes Castillo, Sergio, Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre d'études spatiales de la biosphère (CESBIO), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), TOSCA, European Project: 245159,EC:FP7:KBBE,FP7-KBBE-2009-3,SIRRIMED(2010), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), and Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)

Subjects
modis, Biodiversité et Ecologie, évapotranspiration, gestion de l'irrigation, crau, cycle hydrologique, camargue, Biodiversity and Ecology, cartographie des propriétés, ressource en eau, landsat tm, impact environnemental, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, ComputingMilieux_MISCELLANEOUS
Abstract

Olioso A., Gallego-Elvira B., Bahir M., Boulet G., Weiss M., Mira M., Castillo-Reyes S., 2015. EVASPA : EVapotranspiration Assessment from SPAce. Workshop modélisation de surface, 30 nov-1 dec 2015, CESBIO (salle de conférence du CESBIO), Toulouse. [Présentation orale par A. Olioso].; National audience

Published
2015

10. Global observational diagnosis of soil moisture control on the land surface energy balance

Author

Gallego-Elvira, Belen, Taylor, Christopher M., Harris, Phil P., Ghent, Darren, Veal, Karen L., Folwell, Sonja S., Gallego-Elvira, Belen, Taylor, Christopher M., Harris, Phil P., Ghent, Darren, Veal, Karen L., and Folwell, Sonja S.

Abstract

An understanding of where and how strongly the surface energy budget is constrained by soil moisture is hindered by a lack of large-scale observations, and this contributes to uncertainty in climate models. Here we present a new approach combining satellite observations of land surface temperature and rainfall.We derive a Relative Warming Rate (RWR) diagnostic, which is a measure of how rapidly the land warms relative to the overlying atmosphere during 10 day dry spells. In our dry spell composites, 73% of the land surface between 60°S and 60°N warms faster than the atmosphere, indicating water-stressed conditions, and increases in sensible heat. Higher RWRs are found for shorter vegetation and bare soil than for tall, deep-rooted vegetation, due to differences in aerodynamic and hydrological properties. We show how the variation of RWR with antecedent rainfall helps to identify different evaporative regimes in the major nonpolar climate zones.

Published
2016

Catalog

Books, media, physical & digital resources
See catalog results