Effect of dew on the radiometric signal over a grass field at L-band
Autor: | M. J. Escorihuela, Yann Kerr, K. Saleh, Jean-Pierre Wigneron, P. de Rosnay, Jean-Christophe Calvet |
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Přispěvatelé: | 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), European Centre for Medium-Range Weather Forecasts (ECMWF), Department of geography, University of Cambridge [UK] (CAM), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Centre national de recherches météorologiques (CNRM), Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Centre National de la Recherche Scientifique (CNRS) |
Jazyk: | angličtina |
Rok vydání: | 2009 |
Předmět: |
010504 meteorology & atmospheric sciences
Planetary boundary layer [SDV]Life Sciences [q-bio] 0211 other engineering and technologies 02 engineering and technology MOISTURE Atmospheric sciences 01 natural sciences RADIOMETRY 14. Life underwater Electrical and Electronic Engineering MICROWAVE Water content 021101 geological & geomatics engineering 0105 earth and related environmental sciences Moisture 15. Life on land Geotechnical Engineering and Engineering Geology Atmospheric temperature RELATION SOL-ATMOSPHERE Salinity SOIL Dew point 13. Climate action Brightness temperature [SDE]Environmental Sciences Environmental science Dew |
Zdroj: | IEEE Geoscience and Remote Sensing Letters IEEE Geoscience and Remote Sensing Letters, IEEE-Institute of Electrical and Electronics Engineers, 2009, 6 (1), pp.67-71. ⟨10.1109/LGRS.2008.2000714⟩ |
ISSN: | 1545-598X 1558-0571 |
DOI: | 10.1109/LGRS.2008.2000714⟩ |
Popis: | International audience; The future Soil Moisture and Ocean Salinity satellite time of overpass is 6 A.m. and 6 P.M. at the equator. In many regions, morning dew is expected at the time of the satellite overpass and might play a role in soil moisture retrievals. The aim of this study was to assess the effects of dew on L-band measurements. Radiometric, biomass, and dew measurements were performed over a natural grass field. Our results show that at the diurnal scale, vegetation internal water content changes play a major role in emission. A direct impact of dew on measurements was not identified. However, a brightness temperature increase of 0.5 and 1 K was observed at vertical and horizontal polarizations' respectively. This increase was detected later after dew, suggesting that it was not directly caused by the presence of dew on the grass blades. Our hypothesis is that the observed increase in brightness temperatures is due to the absorption of dew water by the litter layer. |
Databáze: | OpenAIRE |
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