19 results on '"Bircher, Simone"'
Search Results
2. Passive L-band microwave remote sensing of organic soil surface layers: a tower-based experiment
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Jonard, François, Bircher, Simone, Demontoux, François, Weihermüller, Lutz, Razafindratsima, Stephen, Wigneron, Jean-Pierre, Vereecken, Harry, Agrosphere, IBG-3, Forschungszentrum Jülich GmbH | Centre de recherche de Juliers, Helmholtz-Gemeinschaft = Helmholtz Association-Helmholtz-Gemeinschaft = Helmholtz Association, Earth and Life Institute [Louvain-La-Neuve] (ELI), Université Catholique de Louvain = Catholic University of Louvain (UCL), 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), Université de Bordeaux (UB), Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), 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)
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stockage du carbone ,microwave remote sensing ,bande l ,[SDV]Life Sciences [q-bio] ,inverse modelling ,bilan hydrique du sol ,soil dielectric permittivity ,tower-based experiment ,sol organique ,L-band radiometry ,organic soil ,soil moisture ,[SDE]Environmental Sciences ,carbone organique du sol ,lcsh:Q ,ddc:620 ,lcsh:Science - Abstract
International audience; Organic soils play a key role in global warming because they store large amount of soil carbon which might be degraded with changing soil temperatures or soil water contents. There is thus a strong need to monitor these soils and, in particular, their hydrological characteristics using, for instance, space-borne L-band brightness temperature observations. However, there are still open issues with respect to soil moisture retrieval techniques over organic soils. In view of this, organic soil blocks with their vegetation cover were collected from a heathland in the Skjern River catchment in western Denmark and then transported to a remote sensing field laboratory in Germany where their structure was reconstituted. The controlled conditions at this field laboratory made it possible to perform tower-based L-band radiometer measurements of the soils over a period of two months. Brightness temperature data were inverted using a radiative transfer (RT) model for estimating the time variations in the soil dielectric permittivity and the vegetation optical depth. In addition, the effective vegetation scattering albedo parameter of the RT model was retrieved based on a two-step inversion approach. The remote estimations of the dielectric permittivity were compared to in situ measurements. The results indicated that the radiometer-derived dielectric permittivities were significantly correlated with the in situ measurements, but their values were systematically lower compared to the in situ ones. This could be explained by the difference between the operating frequency of the L-band radiometer (1.4 GHz) and that of the in situ sensors (70 MHz). The effective vegetation scattering albedo parameter was found to be polarization dependent. While the scattering effect within the vegetation could be neglected at horizontal polarization, it was found to be important at vertical polarization. The vegetation optical depth estimated values over time oscillated between 0.10 and 0.19 with a mean value of 0.13. This study provides further insights into the characterization of the L-band brightness temperature signatures of organic soil surface layers and, in particular, into the parametrization of the RT model for these specific soils. Therefore, the results of this study are expected to improve the performance of space-borne remote sensing soil moisture products over areas dominated by organic soils.
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- 2018
3. Modeling soil evaporation efficiency in a range of soil and atmospheric conditions using a meta-analysis approach
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Merlin, Olivier, Stefan, Vivien, Amazirh, A, Chanzy, A, Ceschia, Eric, Er-Raki, S, Gentine, P, Tallec, Tiphaine, Ezzahar, J, Bircher, Simone, Beringer, J, Khabba, S, 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), Faculté des Sciences SEMLALIA (FSSM), Université Cadi Ayyad [Marrakech] (UCA), Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Department of Earth and Environmental Engineering [New York], Columbia University [New York], School of Earth and Environment, University of Western Australia, The University of Western Australia (UWA), This study was supported by the French Agence Nationale de la Recherche (MIXMOD-E project, ANR-13-JS06-0003-01) and the European Commission Horizon 2020 Programme for Research and Innovation (H2020) in the context of the Marie Sklodowska-Curie Research and Innovation Staff Exchange (RISE) action (REC project, grant agreement no: 645642)., 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), 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 Faculté des Sciences Semlalia [Marrakech]
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moisture ,modeling ,[SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology ,texture ,evaporation ,soil - Abstract
International audience; A meta-analysis data-driven approach is developed to represent the soil evaporative efficiency (SEE) defined as the ratio of actual to potential soil evaporation. The new model is tested across a bare soil database composed of more than 30 sites around the world, a clay fraction range of 0.02-0.56, a sand fraction range of 0.05-0.92, and about 30,000 acquisition times. SEE is modeled using a soil resistance ($r_{ss}$) formulation based on surface soil moisture ($\theta$) and two resistance parameters $r_{ss,ref}$ and $\theta_{efolding}$. The data-driven approach aims to express both parameters as a function of observable data including meteorological forcing, cut-off soil moisture value $\theta_{1/2}$ at which SEE=0.5, and first derivative of SEE at $\theta_{1/2}$, named $\Delta\theta_{1/2}^{-1}$. An analytical relationship between $(r_{ss,ref};\theta_{efolding})$ and $(\theta_{1/2};\Delta\theta_{1/2}^{-1})$ is first built by running a soil energy balance model for two extreme conditions with $r_{ss} = 0$ and $r_{ss}\sim\infty$ using meteorological forcing solely, and by approaching the middle point from the two (wet and dry) reference points. Two different methods are then investigated to estimate the pair $(\theta_{1/2} ; \Delta\theta_{1/2}^{-1})$ either from the time series of SEE and $\theta$ observations for a given site, or using the soil texture information for all sites. The first method is based on an algorithm specifically designed to accomodate for strongly nonlinear $\text{SEE}(\theta)$ relationships and potentially large random deviations of observed SEE from the mean observed $\text{SEE}(\theta)$. The second method parameterizes $\theta_{1/2}$ as a multi-linear regression of clay and sand percentages, and sets $\Delta\theta_{1/2}^{-1}$ to a constant mean value for all sites. The new model significantly outperformed the evaporation modules of ISBA (Interaction Sol-Biosph\`{e}re-Atmosph\`{e}re), H-TESSEL (Hydrology-Tiled ECMWF Scheme for Surface Exchange over Land), and CLM (Community Land Model). It has potential for integration in various land-surface schemes, and real calibration capabilities using combined thermal and microwave remote sensing data.
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- 2016
4. L-Band Relative Permittivity of Organic Soil Surface Layers—A New Dataset of Resonant Cavity Measurements and Model Evaluation
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Bircher, Simone, primary, Demontoux, François, additional, Razafindratsima, Stephen, additional, Zakharova, Elena, additional, Drusch, Matthias, additional, Wigneron, Jean-Pierre, additional, and Kerr, Yann, additional
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- 2016
- Full Text
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5. Soil moisture and dielectric constant measurements of organic soils in the higher northern latitudes in support of the SMOS mission
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Bircher, Simone, Razafindratsima, Stephen, Demontoux, François, Andreasen, Mie, Vuollet, Johanna, Rautiainen, Kimmo, Jonard, François, Weihermüller, Lutz, Richaume, Philippe, Mialon, Arnaud, Wigneron, Jean-Pierre, Kerr, Yann H., 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 de l'intégration, du matériau au système (IMS), Université Sciences et Technologies - Bordeaux 1-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), Université de Bordeaux (UB), Department of Geosciences and Natural Resource Management [Copenhagen] (IGN), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), Finnish Meteorological Institute (FMI), Institute of Bio- and Geosciences Agrosphere (IBG-3), Research Center Jülich, Germany, ∗Agrosphere (IBG-3), Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, Jülich, Germany, Institute of Bio- and Geosciences [Jülich] (IBG), Forschungszentrum Jülich GmbH-Forschungszentrum Jülich GmbH-Institute of Bio- and Geosciences [Jülich] (IBG), Forschungszentrum Jülich GmbH-Forschungszentrum Jülich GmbH, Institute of Bio- and Geosciences Agrosphere (IBG-3), Écologie fonctionnelle et physique de l'environnement (EPHYSE - UR1263), Institut National de la Recherche Agronomique (INRA), Institut national des sciences de l'Univers (INSU - CNRS), Université Sciences et Technologies - Bordeaux 1 (UB), University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), Forschungszentrum Jülich GmbH | Centre de recherche de Juliers, Helmholtz-Gemeinschaft = Helmholtz Association, 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), Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Université McGill [Montréal]. CAN., Université Sciences et Technologies - Bordeaux 1, 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), and Écologie fonctionnelle et physique de l'environnement (EPHYSE)
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[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism ,Electromagnetism ,[SDE.MCG]Environmental Sciences/Global Changes ,Signal and Image processing ,Traitement du signal et de l'image ,Electromagnétisme ,Milieux et Changements globaux ,[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment ,[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2014
6. Comparison of SMOS level 2 and level 3 soil moisture at the SMOSREX site
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Mialon, Arnaud, Cabot, François, Guibert, Sarah, Ahmad, Al Bitar, Richaume, Philippe, Wigneron, Jean-Pierre, Pellarin, Thierry, Tarot, Stéphane, Bircher, Simone, Grant, Jennifer, Rodriguez‐Fernandez, Nemesio, Kerr, Yann H., Centre d'études spatiales de la biosphère (CESBIO), 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 d’Etudes Spatiales, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Laboratoire d'étude des transferts en hydrologie et environnement (LTHE), Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), SISMER, Lund University [Lund], Université McGill [Montréal]. CAN., 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), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Systèmes d'Information Scientifique pour la Mer (SISMER), Infrastructures de Recherche et Systèmes d'Information (IRSI), and Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)
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sol nu ,télédétection ,Signal and Image processing ,Earth Sciences ,prairie ,Traitement du signal et de l'image ,projet smos ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,donnée satellite ,[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing ,Sciences de la Terre ,smosrex - Abstract
International audience; The ESA (European Space Agency) satellite mission SMOS (Soil Moisture and Ocean Salinity) was launched in November 2009 and has been providing data on ocean salinity and soil moisture over continental surfaces for the last 4 years. SMOS satellite is a passive L-band (1.4 GHz) interferometer that measures the surface soil moisture (top 5cm) with an overpass time at 6 am and 6 pm (local time) and a radiometric resolution of ~ 43 km in average. With a quasi polar orbit, it covers the entire Earth surface in 3 days. The CATDS (Centre Aval de Traitements des Données SMOS) ground segment developed by the French space agency CNES, provides so called “level 3” soil moisture products that are time aggregated products, on the EASE (Equal Area Scalable Earth) Grid with a ~25 km spatial resolution. The retrieval algorithm is based on the radiative model L-MEB (L-band Microwave Emission of the Biosphere). The aim of this paper is to present the different soil moisture products that are delivered by the CATDS such as daily products, 3-day and 10-day composites, monthly averages, discuss different features of the product contents, and also presenting the validation of the SMOS data. Several in-situ sites are equipped with various soil moisture sensors providing soil moisture measurements for different climate areas. For instance, the SMOSREX (Surface Monitoring of the Soil Reservoir Experiment) site was developed to test the SMOS soil moisture retrieval algorithm. Two fields (bare soil and grassland) were monitored with Delta-T theta probes and a cosmic ray neutrons probe that measures the soil moisture over a large area (~ 700m). This site was stopped in 2012 which provides us with more than two years of data that can be compared to SMOS derived soil moisture values.
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- 2014
7. SMOSHiLat - Microwave L-band emission from organic-rich soils in the northern cold climate zone in the framework of the SMOS mission
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Bircher, Simone, Demontoux, François, Jensen, Karsten Høgh, Jonard, François, Kerr, Yann, Mialon, Arnaud, Mironov, Valery, Pulliainen, J., Rautiainen, K., Razafindratsima, Stephen, Richaume, P., Schwank, M., Weihermüller, Lutz, Wigneron, Jean Pierre, 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 de l'intégration, du matériau au système (IMS), Université Sciences et Technologies - Bordeaux 1-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), Radiophysics of remote sensing laboratory, Kirensky Institute of Physics, Allergy Unit - Department of Dermatology, University of Zürich [Zürich] (UZH), Écologie fonctionnelle et physique de l'environnement (EPHYSE - UR1263), Institut National de la Recherche Agronomique (INRA), 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), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Université Sciences et Technologies - Bordeaux 1, Gamma Remote Sensing, Forschungszentrum Jülich GmbH | Centre de recherche de Juliers, Helmholtz-Gemeinschaft = Helmholtz Association, Laboratory of Radiophysics of the Earth Remote Sensing, Partenaires INRAE, Finnish Meteorological Institute (FMI), University of Copenhagen = Københavns Universitet (KU), Institute of Electrical and Electronics Engineers (IEEE). USA., 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), Université Sciences et Technologies - Bordeaux 1 (UB), and University of Copenhagen = Københavns Universitet (UCPH)
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SMOSHiLat ,[SDE.MCG]Environmental Sciences/Global Changes ,Signal and Image processing ,dielectric constants ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,radiometer ,Sciences de la Terre ,[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism ,moisture ,Earth Sciences ,Traitement du signal et de l'image ,L Band ,Milieux et Changements globaux ,[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment ,organic soil ,[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing - Abstract
International audience; The circumpolar northern colder climate zone (boreal zone/tundra) is covered by pronounced organic soils. Due to above-average rising temperatures in the higher northern latitudes, a large amount of these important carbon sinks might be released, possibly causing a significant positive feedback on global warming. Thus, there is a strong need to monitor hydrologic processes in these regions. The ESA's Soil Moisture and Ocean Salinity (SMOS) mission carries the first space-borne passive L-band microwave (1.4 GHz) radiometer on board. It acquires global brightness temperatures (TB) from which surface soil moisture is retrieved, taking advantage of the very large difference between the dielectric constant of dry soil and water at this frequency. The retrieval algorithm is based on the L-band Microwave Emission of the Biosphere (L-MEB) model which uses tuning parameters derived from study sites in dry and warm temperate climate zones. In order to improve our understanding of L-band emissions of organic soil surface layers and thus, supporting the quality of SMOS data in the northern colder climate zone the SMOSHiLat project has been evoked in the framework of ESA's Changing Earth Science Network. It aims at creating a database including L-band TBs and dielectric constant values of soils, mainly from two northern study sites in Sodankylä, Finland (Finnish Meteorological Institue, FMI), and Gludsted, Denmark (Hydrologic OBsErvatory, HOBE). Based on this database the L-MEB model is adapted for organic soils encountered in Northern regions and tested in the SMOS soil moisture prototype retrieval algorithm in view of its implementation in the operational one.
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- 2014
8. The Sodankylä in situ soil moisture observation network: an example application of ESA CCI soil moisture product evaluation
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Ikonen, Jaakko, primary, Vehviläinen, Juho, additional, Rautiainen, Kimmo, additional, Smolander, Tuomo, additional, Lemmetyinen, Juha, additional, Bircher, Simone, additional, and Pulliainen, Jouni, additional
- Published
- 2016
- Full Text
- View/download PDF
9. Soil moisture sensor calibration for organic soil surface layers
- Author
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Bircher, Simone, primary, Andreasen, Mie, additional, Vuollet, Johanna, additional, Vehviläinen, Juho, additional, Rautiainen, Kimmo, additional, Jonard, François, additional, Weihermüller, Lutz, additional, Zakharova, Elena, additional, Wigneron, Jean-Pierre, additional, and Kerr, Yann H., additional
- Published
- 2016
- Full Text
- View/download PDF
10. SMOS validation results from the HOBE site, Denmark
- Author
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Bircher, Simone, Richaume, Philippe, Mialon, Arnaud, Berthon, Lucie, Cabot, François, Ahmad, Al Bitar, Merlin, Olivier, Wigneron, Jean-Pierre, Balling, Jan, Skou, Niels, Jensen, Karsten Høgh, Kerr, Yann H., Centre d'études spatiales de la biosphère (CESBIO), 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), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Technical University of Denmark [Lyngby] (DTU), University of Copenhagen = Københavns Universitet (KU), 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), Danmarks Tekniske Universitet = Technical University of Denmark (DTU), and University of Copenhagen = Københavns Universitet (UCPH)
- Subjects
[SDV]Life Sciences [q-bio] ,télédétection par satellite ,[SDE]Environmental Sciences ,projet smos ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2013
11. Microwave L-band dielectric constant and brightness temperature estimates of organic rich soils in the Boreal zone
- Author
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Bircher, Simone, Wigneron, Jean-Pierre, Demontoux, François, Rautienen, Kimmo, Pulliainen, Jouni, Richaume, Philippe, Schwank, Mike, Mironov, Valery, Seppänen, Jaakko, Kerr, Yann H., 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), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Université Sciences et Technologies - Bordeaux 1 (UB), Finnish Meteorological Institute (FMI), Gamma Remote Sensing, Russian Academy of Sciences [Moscow] (RAS), School of Electrical Engineering [Aalto Univ], Aalto University, 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), and Université Sciences et Technologies - Bordeaux 1
- Subjects
télédétection ,[SDE.MCG]Environmental Sciences/Global Changes ,microonde ,température de brillance ,Milieux et Changements globaux ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2013
12. Validation of SMOS level 3 soil moisture
- Author
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Mialon, Arnaud, Ahmad, Al Bitar, Berthon, Lucie, Bircher, Simone, Cabot, François, Escorihuela, Maria-José, Leroux, Delphine, Merlin, Olivier, Novello, Nathalie, Pellarin, Thierry, Wigneron, Jean-Pierre, Kerr, Yann H., Centre d'études spatiales de la biosphère (CESBIO), 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), Department of Geosciences and Natural Resource Management [Copenhagen] (IGN), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), isardSAT, Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Laboratoire d’étude des Transferts en Hydrologie et Environnement (LTHE), Institute of Electrical and Electronics Engineers (IEEE). USA., 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), University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), Laboratoire d'étude des transferts en hydrologie et environnement (LTHE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
analyse de données ,télédétection ,[SDV]Life Sciences [q-bio] ,[SDE]Environmental Sciences ,projet smos ,humidité du sol ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2012
13. SMOS soil moisture Cal Val activities
- Author
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Kerr, Yann H., Mialon, Arnaud, Ahmad, Al Bitar, Leroux, Delphine, Richaume, Philippe, Gruhier, Claire, Berthon, Lucie, Novello, Nathalie, Rüdiger, Christoph, Bircher, Simone, Wigneron, Jean-Pierre, Ferrazzoli, Paolo, Rahmoune, Rachid, Centre d'études spatiales de la biosphère (CESBIO), 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), Vega Technologies, Partenaires INRAE, Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Monash University, Technical University of Denmark [Lyngby] (DTU), Università degli Studi di Roma Tor Vergata [Roma], 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), and Danmarks Tekniske Universitet = Technical University of Denmark (DTU)
- Subjects
mission SMOS ,analyse de données ,Geography ,télédétection ,satellite ,capteur ,[SHS.GEO]Humanities and Social Sciences/Geography ,Géographie ,radiométrie ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2012
14. SMOS validation in the Skjern River Catchment, Denmark
- Author
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Bircher, Simone
- Abstract
Soil moisture is a key variable for water resources management, weather and climate predictions as well as hazard analysis. It is highly variable in space and time across scales, and thus difficult to assess. The European Space Agency’s Soil Moisture and Ocean Salinity (SMOS) satellite with a passive L-band microwave radiometer on board is the first mission dedicated to surface soil moisture monitoring from space with global coverage every three days. By means of a complex retrieval algorithm, soil moisture is derived from the acquired brightness temperatures. Currently, data validation is performed across a range of climatic regions. In this context, the overall objective of this dissertation is SMOS validation in the Skjern River Catchment in Denmark, including the acquisition of the required in situ data, and its comparison with the SMOS products. Data collection included a short-term airborne campaign with the L-band radiometer EMIRAD-2 and in situ measurements, as well as the establishment of a soil moisture and temperature network. To a priori increase the probability of a representative network average at SMOS scale (∼40-50 km), a method based on analysis of the prevailing environmental conditions was developed and successfully applied. In addition to retrieved soil moisture,validation also involved SMOS brightness temperature data and the most sensitive parameters of the retrieval algorithm. Using two complementary data sets allowed for comprehensive analysis over spatial and temporal scales. While the campaign data set of high spatial coverage and density proved of value for site-specific determination of important algorithm parameters, the long-term network record enables the assessment of temporal trends. Consistent with worldwide findings, results show that SMOS well captures the temporalsoil moisture dynamics in the Skjern River Catchment. However, the retrieved soil moisture shows a constant dry-bias and exhibits a stronger precipitation response compared to the in situ measurements. In addition to the broadly discussed Radio Frequency Interferences (RFI) and a mismatch in sampling depth between in situ sensors and L-band emission depth, several inaccuracies in the algorithm could be located as most likely error sources at the Danish site. This includes the vegetation optical depth and surface roughness parameters,soil properties and the Dobson dielectric mixing model. This dissertation is not only a valuable contribution to SMOS validation, but can also be supportive for upcoming space missions such as NASA’s Soil Moisture Active and Passive,SMAP. Knowing the current caveats the use of SMOS data in regional and global modeling of water resources and climate can be initiated. Future work in the Skjern River Catchment will focus on the disclosed error sources, as well as the influence of organic layers by means of not yet explored campaign data.
- Published
- 2011
15. Comparison of Dobson and Mironov Dielectric Models in the SMOS Soil Moisture Retrieval Algorithm
- Author
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Mialon, Arnaud, primary, Richaume, Philippe, additional, Leroux, Delphine, additional, Bircher, Simone, additional, Bitar, Ahmad Al, additional, Pellarin, Thierry, additional, Wigneron, Jean-Pierre, additional, and Kerr, Yann H., additional
- Published
- 2015
- Full Text
- View/download PDF
16. Validation of SMOS L1C and L2 Products and Important Parameters of the Retrieval Algorithm in the Skjern River Catchment, Western Denmark
- Author
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Bircher, Simone, primary, Skou, Niels, additional, and Kerr, Yann H., additional
- Published
- 2013
- Full Text
- View/download PDF
17. Validation of SMOS Brightness Temperatures During the HOBE Airborne Campaign, Western Denmark
- Author
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Bircher, Simone, primary, Balling, Jan E., additional, Skou, Niels, additional, and Kerr, Yann H., additional
- Published
- 2012
- Full Text
- View/download PDF
18. Soil moisture sensor calibration for organic soil surface layers.
- Author
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Bircher, Simone, Andreasen, Mie, Vuollet, Johanna, Vehviläinen, Juho, Rautiainen, Kimmo, Jonard, François, Weihermüller, Lutz, Zakharova, Elena, Wigneron, Jean-Pierre, and Kerr, Yann H.
- Subjects
- *
SOIL moisture , *REMOTE sensing , *CALIBRATION , *PERMITTIVITY , *DETECTORS , *HISTOSOLS - Abstract
This paper’s objective is to present generic calibration functions for organic surface layers derived for the soil moisture sensors Decagon ECH2O 5TE and Delta-T ThetaProbe ML2x, using material from northern regions, mainly from the Finnish Meteorological Institute’s Arctic Research Center in Sodankylä and the study area of the Danish Center for Hydrology (HOBE). For the Decagon 5TE sensor such a function is currently not reported in the literature. Data were compared with measurements from underlying mineral soils including laboratory and field measurements. Shrinkage and charring during drying were considered. For both sensors all field and lab data showed consistent trends. For mineral layers with low soil organic matter (SOM) content the validity of the manufacturer’s calibrations was demonstrated. Deviating sensor outputs in organic and mineral horizons were identified. For the Decagon 5TE, apparent relative permittivities at a given moisture content decreased for increased SOM content, which was attributed to an increase of bound water in organic materials with large specific surface areas compared to the studied mineral soils. ThetaProbe measurements from organic horizons showed stronger nonlinearity in the sensor response and signal saturation in the high-level data. The derived calibration fit functions between sensor response and volumetric water content hold for samples spanning a wide range of humus types with differing SOM characteristics. This strengthens confidence in their validity under various conditions, rendering them highly suitable for large-scale applications in remote sensing and land surface modeling studies. Agreement between independent Decagon 5TE and ThetaProbe time series from an organic surface layer at the Sodankylä site was significantly improved when the here-proposed fit functions were used. Decagon 5TE data also well-reflected precipitation events. Thus, Decagon 5TE network data from organic surface layers at the Sodankylä and HOBE sites are based on the hereproposed natural log fit. The newly derived ThetaProbe fit functions should be used for hand-held applications only, but prove to be of value for the acquisition of instantaneous large-scale soil moisture estimates. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
19. The Sodankylä in situ soil moisture observation network: an example application of ESA CCI soil moisture product evaluation.
- Author
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Ikonen, Jaakko, Vehviläinen, Juho, Rautiainen, Kimmo, Smolander, Tuomo, Lemmetyinen, Juha, Bircher, Simone, and Pulliainen, Jouni
- Subjects
SOIL moisture ,SOIL temperature ,REMOTE sensing ,CLIMATE change - Abstract
During the last decade there has been considerable development in remote sensing techniques relating to soil moisture retrievals over large areas. Within the framework of the European Space Agency’s (ESA) Climate Change Initiative (CCI) a new soil moisture product has been generated, merging different satellite-based surface soil moisture based products. Such remotely sensed data need to be validated by means of in situ observations in different climatic regions. In that context, a comprehensive, distributed network of in situ measurement stations gathering information on soil moisture, as well as soil temperature, has been set up in recent years at the Finnish Meteorological Institute’s (FMI) Sodankylä Arctic research station. The network forms a calibration and validation (CAL–VAL) reference site and is used as a tool to evaluate the validity of satellite retrievals of soil properties. In this paper we present the Sodankylä CAL–VAL reference site soil moisture observation network, its instrumentation as well as its areal representativeness over the study area and the region in general as a whole. As an example of data utilization, comparisons of spatially weighted average top-layer soil moisture observations between the years 2012 and 2014 against ESA CCI soil moisture data product estimates are presented and discussed. The comparisons were made against a single ESA CCI data product pixel encapsulating most of the Sodankylä CAL–VAL network sites. Comparisons are made with daily averaged and running weekly averaged soil moisture data as well as through application of an exponential soil moisture filter. The overall achieved correlation between the ESA CCI data product and in situ observations varies considerably (from 0.479 to 0.637) depending on the applied comparison perspective. Similarly, depending on the comparison perspective used, inter-annual correlation comparison results exhibit even more pronounced variation, ranging from 0.166 to 0.840. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
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