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Comparing the performance of turbulent kinetic energy and K-profile parameterization vertical parameterization schemes over the tropical indian ocean / Lokesh Kumar Pandey in Marine geodesy, vol 44 n° 1 (January 2021)
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Titre : Comparing the performance of turbulent kinetic energy and K-profile parameterization vertical parameterization schemes over the tropical indian ocean Type de document : Article/Communication Auteurs : Lokesh Kumar Pandey, Auteur ; Suneet Dwivedi, Auteur Année de publication : 2021 Article en page(s) : pp 42 - 69 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Océanographie
[Termes descripteurs IGN] Bengale, golfe du
[Termes descripteurs IGN] énergie cinétique
[Termes descripteurs IGN] Indien (océan)
[Termes descripteurs IGN] modélisation spatiale
[Termes descripteurs IGN] mousson
[Termes descripteurs IGN] salinité
[Termes descripteurs IGN] température de surface de la merRésumé : (Auteur) The performance of vertical parameterization schemes, namely, turbulent kinetic energy (TKE) and K-profile parameterization (KPP), is evaluated over the domain [30E-120E; 20S-30N] in the Indian Ocean using the Nucleus for European Modeling of the Ocean (NEMO) regional model. The surface and sub-surface hydrography and mixed layer depth (MLD) of the simulations using TKE and KPP schemes have been compared. The KPP scheme produces higher bias (∼0.5 °C) of sea surface temperature (SST) in monsoon and post-monsoon seasons, which reduces on using the TKE scheme. The maximum surface salinity difference (0.45 psu) between TKE and KPP simulations is obtained over the head Bay of Bengal (BoB) in the post-monsoon months. The KPP scheme also overestimates MLD of the region. Barring highly convective regions as well as regions marked with very low and rapidly changing salinity, the TKE scheme performs better than KPP scheme in simulating the hydrography and MLD of the region. The differences between TKE and KPP simulations in the vertical stability and mixing are studied using buoyancy frequency, vertical shear of horizontal currents and energy required for mixing as quantifiers. The mixed layer heat budget analysis explains seasonal variability of SST and differences in vertical mixing parameterizations. Numéro de notice : A2021-059 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01490419.2020.1835758 date de publication en ligne : 29/10/2020 En ligne : https://doi.org/10.1080/01490419.2020.1835758 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96849
in Marine geodesy > vol 44 n° 1 (January 2021) . - pp 42 - 69[article]The construction of sound speed field based on back propagation neural network in the global ocean / Junting Wang in Marine geodesy, vol 43 n° 6 (November 2020)
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Titre : The construction of sound speed field based on back propagation neural network in the global ocean Type de document : Article/Communication Auteurs : Junting Wang, Auteur ; Tianhe Xu, Auteur ; Wenfeng Nie, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 621 - 642 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes descripteurs IGN] fonction orthogonale
[Termes descripteurs IGN] interpolation spatiale
[Termes descripteurs IGN] milieu marin
[Termes descripteurs IGN] onde acoustique
[Termes descripteurs IGN] propagation du son
[Termes descripteurs IGN] réseau neuronal artificiel
[Termes descripteurs IGN] salinité
[Termes descripteurs IGN] sondage acoustique
[Termes descripteurs IGN] température
[Termes descripteurs IGN] vitesseRésumé : (auteur) The sound speed is a key parameter that affects the underwater acoustic positioning and navigation. Aiming at the high-precision construction of sound speed field in the complex marine environment, this paper proposes a sound speed field model based on back propagation neural network (BPNN) by considering the correlation of learning samples. The method firstly uses measured ocean parameters to construct the temperature and salinity field. Then the spatial position, the temperature and the salinity information are used to construct the global ocean sound speed field based on the back propagation neural network algorithm. During the processing, the learning samples of back propagation neural network are selected based on the correlation between sound speed and distance. The proposed algorithm is validated by the global Argo data as well as compared with the spatial interpolation and the empirical orthogonal function (EOF) algorithm. The results demonstrate that the average root mean squares of the BPNN considering the correlation of learning samples is 0.352 m/s compared to the 1.527 m/s of EOF construction and the 2.661 m/s of spatial interpolation, with an improvement of 76.9% and 86.8%. Therefore, the proposed algorithm can improve the construction accuracy of sound speed field in the complex marine environment. Numéro de notice : A2020-694 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01490419.2020.1815912 date de publication en ligne : 14/09/2020 En ligne : https://doi.org/10.1080/01490419.2020.1815912 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96242
in Marine geodesy > vol 43 n° 6 (November 2020) . - pp 621 - 642[article]Using Ranked Probability Skill Score (RPSS) as Nonlocal Root-Mean-Square Errors (RMSEs) for Mitigating Wet Bias of Soil Moisture Ocean Salinity (SMOS) Soil Moisture / Ju Hyoung Lee in Photogrammetric Engineering & Remote Sensing, PERS, vol 86 n° 2 (February 2020)
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Titre : Using Ranked Probability Skill Score (RPSS) as Nonlocal Root-Mean-Square Errors (RMSEs) for Mitigating Wet Bias of Soil Moisture Ocean Salinity (SMOS) Soil Moisture Type de document : Article/Communication Auteurs : Ju Hyoung Lee, Auteur Année de publication : 2020 Article en page(s) : pp 91 - 98 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes descripteurs IGN] Afrique occidentale
[Termes descripteurs IGN] données multitemporelles
[Termes descripteurs IGN] erreur moyenne quadratique
[Termes descripteurs IGN] erreur systématique
[Termes descripteurs IGN] humidité du sol
[Termes descripteurs IGN] image SMOS
[Termes descripteurs IGN] salinitéRésumé : (Auteur) To mitigate instantaneously evolving biases in satellite retrievals, a stochastic approach is applied over West Africa. This stochastic approach independently self-corrects Soil Moisture Ocean Salinity (SMOS) wet biases, unlike the cumulative density function (CDF) matching that rescales satellite retrievals with respect to several years of reference data. Ranked probability skill score (RPSS) is used as nonlocal root-mean-square errors (RMSEs) to assess stochastic retrievals. Stochastic method successfully decreases RMSEs from 0.146 m3/m3 to 0.056 m3/m3 in the Republic of Benin and from 0.080 m3/m3 to 0.038 m3/m3 in Niger, while the CDF matching method exacerbates the original SMOS biases up to 0.141 m3/m3 in Niger, and 0.120 m3/m3 in Benin. Unlike the CDF matching or European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA))–interim soil moisture, only a stochastic retrieval responds to Tropical Rainfall Measuring Mission rainfall. Based on the effects of bias correction, RPSS is suggested as a nonlocal verification without needing local measurements. Numéro de notice : A2020-126 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.14358/PERS.86.2.91 date de publication en ligne : 01/02/2020 En ligne : https://doi.org/10.14358/PERS.86.2.91 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94772
in Photogrammetric Engineering & Remote Sensing, PERS > vol 86 n° 2 (February 2020) . - pp 91 - 98[article]On the assimilation of absolute geodetic dynamic topography in a global ocean model: impact on the deep ocean state / Alexey Androsov in Journal of geodesy, vol 93 n° 2 (February 2019)
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Titre : On the assimilation of absolute geodetic dynamic topography in a global ocean model: impact on the deep ocean state Type de document : Article/Communication Auteurs : Alexey Androsov, Auteur ; Lars Nerger, Auteur ; Reiner Schnur, Auteur ; Alberta Albertella, Auteur ; Reiner Rummel, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 141 - 157 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes descripteurs IGN] assimilation des données
[Termes descripteurs IGN] circulation océanique
[Termes descripteurs IGN] données altimétriques
[Termes descripteurs IGN] données CHAMP
[Termes descripteurs IGN] données GOCE
[Termes descripteurs IGN] données GRACE
[Termes descripteurs IGN] filtre de Kalman
[Termes descripteurs IGN] geoïde marin
[Termes descripteurs IGN] géoïde terrestre
[Termes descripteurs IGN] hauteurs de mer
[Termes descripteurs IGN] modèle de simulation
[Termes descripteurs IGN] modèle océanographique
[Termes descripteurs IGN] océanographie dynamique
[Termes descripteurs IGN] salinité
[Termes descripteurs IGN] température de surface de la merRésumé : (auteur) General ocean circulation models are not perfect. Forced with observed atmospheric fluxes they gradually drift away from measured distributions of temperature and salinity. We suggest data assimilation of absolute dynamical ocean topography (DOT) observed from space geodetic missions as an option to reduce these differences. Sea surface information of DOT is transferred into the deep ocean by defining the analysed ocean state as a weighted average of an ensemble of fully consistent model solutions using an error-subspace ensemble Kalman filter technique. Success of the technique is demonstrated by assimilation into a global configuration of the ocean circulation model FESOM over 1 year. The dynamic ocean topography data are obtained from a combination of multi-satellite altimetry and geoid measurements. The assimilation result is assessed using independent temperature and salinity analysis derived from profiling buoys of the AGRO float data set. The largest impact of the assimilation occurs at the first few analysis steps where both the model ocean topography and the steric height (i.e. temperature and salinity) are improved. The continued data assimilation over 1 year further improves the model state gradually. Deep ocean fields quickly adjust in a sustained manner: A model forecast initialized from the model state estimated by the data assimilation after only 1 month shows that improvements induced by the data assimilation remain in the model state for a long time. Even after 11 months, the modelled ocean topography and temperature fields show smaller errors than the model forecast without any data assimilation. Numéro de notice : A2019-076 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-018-1151-1 date de publication en ligne : 12/05/2018 En ligne : https://doi.org/10.1007/s00190-018-1151-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92190
in Journal of geodesy > vol 93 n° 2 (February 2019) . - pp 141 - 157[article]Modelling electrical conductivity of soil from backscattering coefficient of microwave remotely sensed data using artificial neural network / Walaiporn Phonphan in Geocarto international, vol 29 n° 7 - 8 (November - December 2014)
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Titre : Modelling electrical conductivity of soil from backscattering coefficient of microwave remotely sensed data using artificial neural network Type de document : Article/Communication Auteurs : Walaiporn Phonphan, Auteur ; Nitin Kumar Tripathi, Auteur ; Taravudh Tipdecho, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 842 - 859 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes descripteurs IGN] conductivité électrique
[Termes descripteurs IGN] image ALOS-PALSAR
[Termes descripteurs IGN] micro-onde
[Termes descripteurs IGN] rétrodiffusion
[Termes descripteurs IGN] salinitéRésumé : (Auteur) Soil salinity is one of the main agricultural problems which expand to larger areas. Soil scientists categorize salinity level by electrical conductivity (EC) measurement. However, field measurements of EC require extensive time, cost and experiences. Remote sensing is one suitable option to investigate and collect spatial data in larger areas. Many researches estimated soil moisture through microwave, but there are fewer studies which mentioned about direct relationship between EC and backscattering coefficient (BC). Thus, this study aims to propose the estimation of EC directly from BC of microwave. The relationship between EC obtained from field survey and BC from microwave is non-linear, artificial neural network (ANN) is one technique proposed in this study to figure out EC and BC relationship. ANN uses multilayer of interconnected processing resulting in EC value with high accuracy which is acceptable. For this reason, ANN model can be successfully utilized as an effective tool for EC estimation from microwave. Numéro de notice : A2014-469 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern En ligne : http://www.tandfonline.com/doi/full/10.1080/10106049.2013.868040#tabModule Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=74046
in Geocarto international > vol 29 n° 7 - 8 (November - December 2014) . - pp 842 - 859[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2014041 RAB Revue Centre de documentation En réserve 3L Disponible Mapping a priori defined plant associations using remotely sensed vegetation characteristics / Hans D. Rölofsen in Remote sensing of environment, vol 140 (January 2014)
PermalinkPermalinkThe soil moisture and ocean salinity (SMOS) mission: first results and achievements / Yann H. Kerr in Revue Française de Photogrammétrie et de Télédétection, n° 200 (Novembre 2012)
PermalinkOverview of the first SMOS sea surface salinity products. Part 1: quality assessment for the second half of 2010 / N. Reul in IEEE Transactions on geoscience and remote sensing, vol 50 n° 5 Tome 1 (May 2012)
PermalinkValidation of the SMOS L2 soil moisture data in the REMEDHUS network (Spain) / N. Sanchez in IEEE Transactions on geoscience and remote sensing, vol 50 n° 5 Tome 1 (May 2012)
PermalinkTélédétection et salinité. Cartographie de la salinité des sols de la plaine algérienne du Bas-Chéliff / A. Douaoui in Géomatique expert, n° 76 (01/09/2010)
PermalinkPermalinkImplementation of an adaptive salinity risk framework in the Condamine catchment, Queensland Murray-Darling Basin, Australia / A. Biggs in International journal of geographical information science IJGIS, vol 23 n°3-4 (march - april 2009)
PermalinkExploring the water cycle of the 'blue planet': the Soil Moisture and Ocean Salinity (SMOS) mission / M. Drinkwater in ESA bulletin, n° 137 (February 2009)
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