Descripteur
Termes IGN > sciences naturelles > sciences de la Terre et de l'univers > géosciences > géographie physique > météorologie > données météorologiques
données météorologiques |
Documents disponibles dans cette catégorie (206)
Ajouter le résultat dans votre panier
Visionner les documents numériques
Affiner la recherche Interroger des sources externes
Etendre la recherche sur niveau(x) vers le bas
A two-stage tropospheric correction model combining data from GNSS and numerical weather model / Jan Douša in GPS solutions, vol 22 n° 3 (July 2018)
[article]
Titre : A two-stage tropospheric correction model combining data from GNSS and numerical weather model Type de document : Article/Communication Auteurs : Jan Douša, Auteur ; Michal Elias, Auteur ; Pavel Vaclavovic, Auteur ; Krystof Eben, Auteur ; Pavel Krč, Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] correction troposphérique
[Termes IGN] données GNSS
[Termes IGN] données météorologiques
[Termes IGN] gradient de troposphère
[Termes IGN] modèle météorologique
[Termes IGN] retard hydrostatique
[Termes IGN] retard troposphérique zénithal
[Termes IGN] station permanenteRésumé : (Auteur) We have developed a new concept for providing tropospheric augmentation corrections. The two-stage correction model combines data from a Numerical Weather Model (NWM) and precise ZTDs estimated from Global Navigation Satellite System (GNSS) permanent stations in regional networks. The first-stage correction is generated using the background NWM forecast only. The second-stage correction results from an optimal combination of the background model data and GNSS (near) real-time tropospheric products. The optimum correction is achieved when using NWM for the hydrostatic delay modeling and for vertical scaling, while GNSS products are used for correcting the non-hydrostatic delay. The method is assessed in several variants including study of the combination of NWM and GNSS data, spatial densification of the original NWM grid, and GNSS ZTD densification using tropospheric linear horizontal gradients. The first-stage correction can be characterized by overall accuracy of about 10 mm for ZTD (1-sigma). The second-stage correction supported with GNSS tropospheric products improved the first-stage correction by a factor of 2–4 in terms of the ZTD accuracy and by a factor of 2.5 in terms of its spatio-temporal stability. Numéro de notice : A2018-373 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-018-0742-x Date de publication en ligne : 29/05/2018 En ligne : https://doi.org/10.1007/s10291-018-0742-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90767
in GPS solutions > vol 22 n° 3 (July 2018)[article]Comparison of total water vapour content in the Arctic derived from GNSS, AIRS, MODIS and SCIAMACHY / Dunya Alraddawi in Atmospheric measurement techniques, vol 11 n° 5 (May 2018)
[article]
Titre : Comparison of total water vapour content in the Arctic derived from GNSS, AIRS, MODIS and SCIAMACHY Type de document : Article/Communication Auteurs : Dunya Alraddawi, Auteur ; Alain Sarkissian, Auteur ; Philippe Keckhut, Auteur ; Olivier Bock , Auteur ; Stefan Noël, Auteur ; Slimane Bekki, Auteur ; Abdanour Irbah, Auteur ; Mustapha Meftah, Auteur ; Chantal Claud, Auteur Année de publication : 2018 Projets : GNSS4SWEC / , VEGAN / Bock, Olivier Article en page(s) : pp 2949 - 2965 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] analyse comparative
[Termes IGN] Arctique
[Termes IGN] Atmospheric Infrared Sounder
[Termes IGN] données GNSS
[Termes IGN] données météorologiques
[Termes IGN] erreur systématique
[Termes IGN] image Aqua-MODIS
[Termes IGN] image Terra-MODIS
[Termes IGN] nébulosité
[Termes IGN] série temporelle
[Termes IGN] teneur en vapeur d'eauRésumé : (auteur) Atmospheric water vapour plays a key role in the Arctic radiation budget, hydrological cycle and hence climate, but its measurement with high accuracy remains an important challenge. Total column water vapour (TCWV) datasets derived from ground-based GNSS measurements are used to assess the quality of different existing satellite TCWV datasets, namely from the Moderate Resolution Imaging Spectroradiometer (MODIS), the Atmospheric Infrared Sounder (AIRS) and the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY). The comparisons between GNSS and satellite data are carried out for three reference Arctic observation sites (Sodankylä, Ny-Ålesund and Thule) where long homogeneous GNSS time series of more than a decade (2001–2014) are available. We select hourly GNSS data that are coincident with overpasses of the different satellites over the three sites and then average them into monthly means that are compared with monthly mean satellite products for different seasons. The agreement between GNSS and satellite time series is generally within 5 % at all sites for most conditions. The weakest correlations are found during summer. Among all the satellite data, AIRS shows the best agreement with GNSS time series, though AIRS TCWV is often slightly too high in drier atmospheres (i.e. high-latitude stations during autumn and winter). SCIAMACHY TCWV data are generally drier than GNSS measurements at all the stations during the summer. This study suggests that these biases are associated with cloud cover, especially at Ny-Ålesund and Thule. The dry biases of MODIS and SCIAMACHY observations are most pronounced at Sodankylä during the snow season (from October to March). Regarding SCIAMACHY, this bias is possibly linked to the fact that the SCIAMACHY TCWV retrieval does not take accurately into account the variations in surface albedo, notably in the presence of snow with a nearby canopy as in Sodankylä. The MODIS bias at Sodankylä is found to be correlated with cloud cover fraction and is also expected to be affected by other atmospheric or surface albedo changes linked for instance to the presence of forests or anthropogenic emissions. Overall, the results point out that a better estimation of seasonally dependent surface albedo and a better consideration of vertically resolved cloud cover are recommended if biases in satellite measurements are to be reduced in the polar regions. Numéro de notice : A2018-240 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.5194/amt-11-2949-2018 Date de publication en ligne : 18/05/2018 En ligne : https://doi.org/10.5194/amt-11-2949-2018 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90215
in Atmospheric measurement techniques > vol 11 n° 5 (May 2018) . - pp 2949 - 2965[article]Modeling tropospheric wet delays with national GNSS reference network in China for BeiDou precise point positioning / Fu Zheng in Journal of geodesy, vol 92 n° 5 (May 2018)
[article]
Titre : Modeling tropospheric wet delays with national GNSS reference network in China for BeiDou precise point positioning Type de document : Article/Communication Auteurs : Fu Zheng, Auteur ; Yidong Lou, Auteur ; Shengfeng Gu, Auteur ; Xiaopeng Gong, Auteur ; Chuang Shi, Auteur Année de publication : 2018 Article en page(s) : pp 545 – 560 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] Chine
[Termes IGN] données météorologiques
[Termes IGN] positionnement par BeiDou
[Termes IGN] positionnement par GPS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] propagation troposphérique
[Termes IGN] retard troposphérique zénithal
[Termes IGN] temps réelRésumé : (Auteur) During past decades, precise point positioning (PPP) has been proven to be a well-known positioning technique for centimeter or decimeter level accuracy. However, it needs long convergence time to get high-accuracy positioning, which limits the prospects of PPP, especially in real-time applications. It is expected that the PPP convergence time can be reduced by introducing high-quality external information, such as ionospheric or tropospheric corrections. In this study, several methods for tropospheric wet delays modeling over wide areas are investigated. A new, improved model is developed, applicable in real-time applications in China. Based on the GPT2w model, a modified parameter of zenith wet delay exponential decay wrt. height is introduced in the modeling of the real-time tropospheric delay. The accuracy of this tropospheric model and GPT2w model in different seasons is evaluated with cross-validation, the root mean square of the zenith troposphere delay (ZTD) is 1.2 and 3.6 cm on average, respectively. On the other hand, this new model proves to be better than the tropospheric modeling based on water-vapor scale height; it can accurately express tropospheric delays up to 10 km altitude, which potentially has benefits in many real-time applications. With the high-accuracy ZTD model, the augmented PPP convergence performance for BeiDou navigation satellite system (BDS) and GPS is evaluated. It shows that the contribution of the high-quality ZTD model on PPP convergence performance has relation with the constellation geometry. As BDS constellation geometry is poorer than GPS, the improvement for BDS PPP is more significant than that for GPS PPP. Compared with standard real-time PPP, the convergence time is reduced by 2–7 and 20–50% for the augmented BDS PPP, while GPS PPP only improves about 6 and 18% (on average), in horizontal and vertical directions, respectively. When GPS and BDS are combined, the geometry is greatly improved, which is good enough to get a reliable PPP solution, the augmentation PPP improves insignificantly comparing with standard PPP. Numéro de notice : A2018-148 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-017-1080-4 Date de publication en ligne : 29/10/2017 En ligne : https://doi.org/10.1007/s00190-017-1080-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89759
in Journal of geodesy > vol 92 n° 5 (May 2018) . - pp 545 – 560[article]Un modèle pour l’intégration spatiale et temporelle de données géolocalisées / Helbert Arenas in Revue internationale de géomatique, vol 28 n° 2 (avril - juin 2018)
[article]
Titre : Un modèle pour l’intégration spatiale et temporelle de données géolocalisées Type de document : Article/Communication Auteurs : Helbert Arenas, Auteur ; Cassia Trojahn, Auteur ; Catherine Comparot, Auteur ; Nathalie Aussenac-Gilles, Auteur Année de publication : 2018 Article en page(s) : pp 243 - 266 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géomatique web
[Termes IGN] données météorologiques
[Termes IGN] données spatiotemporelles
[Termes IGN] intégration de données
[Termes IGN] jeu de données localisées
[Termes IGN] métadonnées
[Termes IGN] modèle sémantique de données
[Termes IGN] ontologie
[Termes IGN] SPARQL
[Termes IGN] web sémantiqueRésumé : (Auteur) Le domaine de l’observation de la Terre est en forte évolution. L’Agence spatiale européenne a récemment lancé les satellites des séries Sentinel qui livrent 8 à 10 To de données par jour, ce qui ouvre de nouvelles opportunités dans les domaines de l’environnement, l’urbanisme, l’océanographie, la climatologie, etc. Les applications métier nécessitent de coupler ces images à des données issues de diverses sources, afin de fournir une meilleure aide à la décision pour des actions à effectuer sur les zones observées. Un des défis à relever est alors l’intégration de ces données hétérogènes. Les technologies du Web sémantique fournissent une infrastructure basée sur des standards de représentation de données et des ontologies, qui jouent un rôle clé dans ce contexte. Notre approche sémantique d’intégration de données enrichit les métadonnées des images satellites par des données de sources pertinentes, décrivant les observations de la Terre en réponse à un besoin donné. Nous proposons un vocabulaire sémantique, formalisant des relations spatio-temporelles et support à l’intégration de divers jeux de données géolocalisées. Nous illustrons notre approche avec un cas d’étude basé sur des données météorologiques. Numéro de notice : A2018-255 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.3166/rig.2018.00055 Date de publication en ligne : 03/08/2018 En ligne : https://doi.org/10.3166/rig.2018.00055 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90318
in Revue internationale de géomatique > vol 28 n° 2 (avril - juin 2018) . - pp 243 - 266[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 047-2018021 SL Revue Centre de documentation Revues en salle Disponible Precipitable water vapour content from ESR/SKYNET sun–sky radiometers : validation against GNSS/GPS and AERONET over three different sites in Europe / Monica Campanelli in Atmospheric measurement techniques, vol 11 n° 1 (January 2018)
[article]
Titre : Precipitable water vapour content from ESR/SKYNET sun–sky radiometers : validation against GNSS/GPS and AERONET over three different sites in Europe Type de document : Article/Communication Auteurs : Monica Campanelli, Auteur ; Alessandra Mascitelli, Auteur ; Paolo Sano, Auteur ; Henri Diémoz, Auteur ; Victor Estellés, Auteur ; Stefano Federico, Auteur ; Anna Maria Iannarelli, Auteur ; Francesca Fratarcangeli, Auteur ; Augusto Mazzoni, Auteur ; Eugenio Realini, Auteur ; Mattia Crespi, Auteur ; Olivier Bock , Auteur ; Jose A. Martínez-Lozano, Auteur ; Stefano Dietrich, Auteur Année de publication : 2018 Projets : 1-Pas de projet / Bock, Olivier Article en page(s) : pp 81 - 94 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Aoste (val d')
[Termes IGN] constante
[Termes IGN] coordonnées GPS
[Termes IGN] données météorologiques
[Termes IGN] données spatiotemporelles
[Termes IGN] étalonnage d'instrument
[Termes IGN] photomètre
[Termes IGN] précipitation
[Termes IGN] retard troposphérique zénithal
[Termes IGN] Rome
[Termes IGN] teneur en vapeur d'eau
[Termes IGN] Valence (Espagne)
[Termes IGN] water vapour radiometerRésumé : (Auteur) The estimation of the precipitable water vapour content (W) with high temporal and spatial resolution is of great interest to both meteorological and climatological studies. Several methodologies based on remote sensing techniques have been recently developed in order to obtain accurate and frequent measurements of this atmospheric parameter. Among them, the relative low cost and easy deployment of sun–sky radiometers, or sun photometers, operating in several international networks, allowed the development of automatic estimations of W from these instruments with high temporal resolution. However, the great problem of this methodology is the estimation of the sun-photometric calibration parameters. The objective of this paper is to validate a new methodology based on the hypothesis that the calibration parameters characterizing the atmospheric transmittance at 940 nm are dependent on vertical profiles of temperature, air pressure and moisture typical of each measurement site. To obtain the calibration parameters some simultaneously seasonal measurements of W, from independent sources, taken over a large range of solar zenith angle and covering a wide range of W, are needed. In this work yearly GNSS/GPS datasets were used for obtaining a table of photometric calibration constants and the methodology was applied and validated in three European ESR-SKYNET network sites, characterized by different atmospheric and climatic conditions: Rome, Valencia and Aosta. Results were validated against the GNSS/GPS and AErosol RObotic NET-work (AERONET) W estimations. In both the validations the agreement was very high, with a percentage RMSD of about 6, 13 and 8 % in the case of GPS intercomparison at Rome, Aosta and Valencia, respectively, and of 8 % in the case of AERONET comparison in Valencia. Analysing the results by W classes, the present methodology was found to clearly improve W estimation at low W content when compared against AERONET in terms of % bias, bringing the agreement with the GPS (considered the reference one) from a % bias of 5.76 to 0.52. Numéro de notice : A2018-053 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.5194/amt-11-81-2018 Date de publication en ligne : 09/01/2018 En ligne : http://dx.doi.org/10.5194/amt-11-81-2018 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89371
in Atmospheric measurement techniques > vol 11 n° 1 (January 2018) . - pp 81 - 94[article]Tropospheric delay modelling for the EGNOS augmentation system / Kamil Kazmierski in Survey review, vol 49 n° 357 (December 2017)PermalinkImproving BeiDou real-time precise point positioning with numerical weather models / Cuixian Lu in Journal of geodesy, vol 91 n° 9 (September 2017)PermalinkApplication of ray-traced tropospheric slant delays to geodetic VLBI analysis / Armin Hofmeister in Journal of geodesy, vol 91 n° 8 (August 2017)PermalinkPerformance evaluation of ionospheric time delay forecasting models using GPS observations at a low-latitude station / G. Sivavaraprasad in Advances in space research, vol 60 n° 2 (15 July 2017)PermalinkIntegrated precipitable water from GPS observations and cimel sunphotometer measurements at CGO Belsk / Michal Kruczyk in Reports on geodesy and geoinformatics, vol 103 n° 1 (June 2017)PermalinkFrequency of extreme Sahelian storms tripled since 1982 in satellite observations / Christopher M. Taylor in Nature letters, vol 544 n° 7651 (27 April 2017)PermalinkStatistical atmospheric parameter retrieval largely benefits from spatial–spectral image compression / Joaquín García-Sobrino in IEEE Transactions on geoscience and remote sensing, vol 55 n° 4 (April 2017)PermalinkTropospheric refractivity and zenith path delays from least-squares collocation of meteorological and GNSS data / Karina Wilgan in Journal of geodesy, vol 91 n° 2 (February 2017)PermalinkStudy of trends and variability of atmospheric water vapour with climate models and observations from global GNSS network / Ana-Claudia Bernardes Parracho (2017)PermalinkA virtual globe-oriented visualization method for 3D meteorological fields / Jing Chen in Geomatics and Information Science of Wuhan University, vol 41 n° 12 (December 2016)Permalink