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GPS based determination of the integrated and spatially distributed water vapor in the troposphere / Marc Troller (2004)
Titre : GPS based determination of the integrated and spatially distributed water vapor in the troposphere Type de document : Thèse/HDR Auteurs : Marc Troller, Auteur Editeur : Zurich : Schweizerischen Geodatischen Kommission / Commission Géodésique Suisse Année de publication : 2004 Collection : Geodätisch-Geophysikalische Arbeiten in der Schweiz, ISSN 0257-1722 num. 67 Importance : 172 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-908440-10-9 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] correction troposphérique
[Termes IGN] distribution spatiale
[Termes IGN] modèle atmosphérique
[Termes IGN] positionnement par GPS
[Termes IGN] propagation troposphérique
[Termes IGN] Suisse
[Termes IGN] teneur en vapeur d'eau
[Termes IGN] tomographie
[Termes IGN] traitement du signal
[Termes IGN] troposphère
[Termes IGN] vapeur d'eauIndex. décimale : 30.84 Applications de géodésie spatiale à l'atmosphère Résumé : (Auteur) Climate change and global warming have become a major challenge for the sustainable development of our Earth and its environment. Intensive research is carried out to understand atmospheric processes and their implications. In this content, water vapor plays a key role. It is an important component of the global energy balance and is involved in many chemical reactions. In microwave measurements, the tropospheric refractivity causes a delay in the arrival of the signal propagating through the atmosphere. This refraction effect is one of the limiting factors in accurate GPS positioning. The tropospheric path delay can be decomposed into a dry and wet part, where the latter part is coupled with the integrated precipitable water vapor above the GPS receiver.
On the one hand, the refraction effect has to be corrected for GPS measurements, on the other hand, it is a valuable signal to determine the spatial distribution of the water vapor. This study investigates both aspects. For the first part, two basic approaches are looked into: One method is based on meteorological measurements. Thereby, the integrated amount of water vapor and its temporal variation are the prime target. The other concept makes use of long-term GPS measurements. The arrival delay of the GPS signals are used, to estimate the integrated amount of water vapor. This result can then be the basis to determine its spatial distribution and temporal behavior. The investigation is based on a tomographic approach and forms the main content of part 2 of this work.
In part 1, an extension of the software package COMEDIE is developed and applied to determine tropospheric path delays. COMEDIE allows a four-dimensional modeling (in space and time) of the meteorological parameters air pressure, temperature and water vapor pressure using a collocation approach. Integrating the meteorological parameters, tropospheric path delays are obtained. Evaluations and comparisons in Switzerland show the performance of this method. An overall good agreement was achieved compared to GPS-estimated path delays. The accuracy depends on the season, and is in the range of 1-2 cm for the tropospheric path delay.
Continuous GPS measurements allow to estimate tropospheric path delays in the GPS processing. In a second approach of part 1, a method based on such GPS-estimated path delays is developed. It uses - like COMEDIE - a four-dimensional model and a collocation adjustment to estimate tropospheric path delays at desired locations. Evaluations are carried out in the area of Switzerland using the permanent GPS network AGNES. Long-term time series of cross-correlations are analyzed. An accuracy of 0.5 - 1.5 cm is obtained.
To resolve the GPS-estimated water vapor in the vertical, a tomographic approach is investigated in part 2 of this study. It is based on the assimilation of GPS double-difference observations. The wet refractivity field is determined applying a least-squares adjustment. To test the performance of the software, different weather conditions are simulated. Various stochastically constrained models are applied and discussed in terms of inversion stability. Results from real data gathered during a dedicated measurement campaign in the high density GPS network of the Big Island of Hawaii are analyzed. Compared to radiosondes, an accuracy of about 10 ppm (refractivity units) is achieved.
To compare the potential and limits of the investigated methods, independent data must be available. An extensive study is performed in the area of Switzerland to evaluate and compare all presented methods with each other. For the validation, data of the numerical weather model aLMo are used. Seven days of data in a high spatial distribution and on an hourly basis are investigated. The tropospheric path delays resulting from the various methods are compared and analyzed. An overall good agreement with the aLMo data was observed. To evaluate the spatial distribution of water vapor, 7680 refractivity profiles are determined with the tomographic method and compared with the numerical weather data. The analysis contains four tomographic approaches including different types of constraints. The results are statistically evaluated and compared. A correlation between the accuracy and the weather situation was found. Overall, an agreement of 5-7 ppm (refractivity units) was achieved compared to aLMo.
In conclusion, it can be stated that the determination of the integrated amount of water vapor in the troposphere was successfully performed. For the main geodetic application, the correction of GPS measurements, the estimation of path delays in the GPS processing is recommended, provided long-terrn GPS phase observations are available. For the determination of the spatial distribution and the temporal variation of the integrated amount of water vapor, modeling of the GPS-estimated path delays is a successful method. Moreover, the principal feasibility to resolve the vertical distribution of the water vapor applying the tomographic approach was demonstrated. However, further investigations concerning constraints or the introduction of additional information are required.Numéro de notice : 13264 Affiliation des auteurs : non IGN Autre URL associée : http://dx.doi.org/10.3929/ethz-a-004796376 Thématique : POSITIONNEMENT Nature : Thèse étrangère DOI : 10.3929/ethz-a-004796376 En ligne : https://www.sgc.ethz.ch/sgc-volumes/sgk-67.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54945 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13264-01 30.84 Livre Centre de documentation Géodésie Disponible 13264-02 30.84 Livre Centre de documentation Géodésie Disponible Estimating local variations in land use statistics / A. Geddes in International journal of geographical information science IJGIS, vol 17 n° 4 (june 2003)
[article]
Titre : Estimating local variations in land use statistics Type de document : Article/Communication Auteurs : A. Geddes, Auteur ; A. Gimona, Auteur ; D.A. Elston, Auteur Année de publication : 2003 Article en page(s) : pp 299 - 319 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Information géographique
[Termes IGN] carte d'occupation du sol
[Termes IGN] classification dirigée
[Termes IGN] distribution spatiale
[Termes IGN] Ecosse
[Termes IGN] estimation statistique
[Termes IGN] géostatistique
[Termes IGN] recensement agricole
[Termes IGN] statistique descriptive
[Termes IGN] système d'information géographique
[Termes IGN] utilisation du sol
[Termes IGN] variable régionaliséeRésumé : (Auteur) The Scottish agricultural census provides land use statistics as summaries for parish areas. We investigated the disaggregation of these parish summaries using the Land Capability for Agriculture and the 1988 Land Cover of Scotland as supporting data sets. It is unlikely that allocation rules to implement the disaggregation should be identical across all parishes. Equally, rules for individual parishes are indeterminate. The 891 parishes were classified into nine classes, then each class was regionalised, creating 91 regions overall. Allocation rules were estimated independently for each region and class. Statistical testing identified greater variations in the rules than is expected by random allocation of regions to classes. Numéro de notice : A2003-095 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/1365881021000026539 En ligne : https://doi.org/10.1080/1365881021000026539 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22391
in International journal of geographical information science IJGIS > vol 17 n° 4 (june 2003) . - pp 299 - 319[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-03041 RAB Revue Centre de documentation En réserve L003 Disponible 079-03042 RAB Revue Centre de documentation En réserve L003 Disponible Introduction à l'analyse spatiale / Jean-Jacques Bavoux (2003)
Titre : Introduction à l'analyse spatiale Type de document : Guide/Manuel Auteurs : Jean-Jacques Bavoux, Éditeur scientifique ; Roger Chapuis, Auteur ; S. Delmer, Auteur ; V. Mannone, Auteur ; Sophie Passegué, Auteur ; P. Volpoet, Auteur Mention d'édition : 2 Editeur : Paris : Armand Colin Année de publication : 2003 Collection : Synthèse Sous-collection : Géographie num. 62 Importance : 95 p. Format : 11 x 18 cm ISBN/ISSN/EAN : 978-2-200-21771-6 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse spatiale
[Termes IGN] approche hiérarchique
[Termes IGN] distance
[Termes IGN] distribution spatiale
[Termes IGN] dynamique spatiale
[Termes IGN] échelle cartographique
[Termes IGN] géopositionnement
[Termes IGN] objet géographique linéaire
[Termes IGN] réseau
[Termes IGN] système d'information géographique
[Termes IGN] territoireRésumé : (Editeur) L'analyse spatiale est aujourd'hui l'une des démarches fondamentales en géographie. Son abord nécessite la maîtrise de notions complexes. Cet ouvrage, qui en facilite l'approche : 1) suit une progression logique ; 2) explique systématiquement le vocabulaire spécialisé ; 3) illustre les concepts par des exemples précis et complets. Note de contenu : Chapitre 1. LES MESURES
1. La mesure : un fondement de l'analyse spatiale
2. Le concept multiforme de distance
3. La distribution spatiale
4. Echelles et différenciations spatiales
Chapitre 2. DES POINTS AUX SURFACES
5. Lieux et localisations
6. Sites et situations
7. Aires et mailles
8. Centres et périphéries
9. Modèles d'organisation de l'espace
Chapitre 3. LES LIGNES
10. Lignes et alignements
11. Les lignes qui relient : les axes
12. Les lignes qui séparent : les limites
Chapitre 4. LES DYNAMIQUES SPATIALES
13. Mobilité et transports
14. Anisotropie spatiale et accessibilité
Chapitre 5. LES DYNAMIQUES TEMPORELLES
15. Expériences du temps
16. Temps naturel et temps historique
17. Le temps comme dimension de l'espace
Chapitre 6. GEOGRAPHIE ET SYSTEMES
18. Le paysage
19. Les réseaux
20. Territoire et région
21. Les systèmes spatiauxNuméro de notice : 18296 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Manuel de cours Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=55369 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 18296-01 37.20 Livre Centre de documentation Géomatique Disponible Landscape dynamics of the spread of sudden oak death / M. Kelly in Photogrammetric Engineering & Remote Sensing, PERS, vol 68 n° 10 (October 2002)
[article]
Titre : Landscape dynamics of the spread of sudden oak death Type de document : Article/Communication Auteurs : M. Kelly, Auteur ; Ross K. Meentemeyer, Auteur Année de publication : 2002 Article en page(s) : pp 1001 - 1009 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse de groupement
[Termes IGN] Californie (Etats-Unis)
[Termes IGN] carte de la végétation
[Termes IGN] classification dirigée
[Termes IGN] classification non dirigée
[Termes IGN] distribution spatiale
[Termes IGN] dynamique spatiale
[Termes IGN] Fagus (genre)
[Termes IGN] forêt
[Termes IGN] image ADAR
[Termes IGN] image multibande
[Termes IGN] indice d'humidité
[Termes IGN] maladie phytosanitaire
[Termes IGN] modélisation spatiale
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] simulation dynamiqueRésumé : (Auteur) Sudden Oak Death is caused by a newly discovered virulent pathogen (Phytophthora ramorum) that is killing thousands of native oak trees in California. We present a landscape-scale study on the spatio-temporal dynamics of oak mortality. Second-order spatial point-pattern analysis techniques (Ripley's K) were applied to the distribution of dead tree crowns (derived from high-resolution imagery) in Marin County, California to determine the existence and scale of mortality clustering in two years (2000 and 2001). Both years showed clustering patterns between 100 and 300 m. A classification tree model was developed to predict spatial patterns of risk for oak mortality based on several landscapescale variables. Proximity to forest edge was the most important explanatory factor, followed by topographic moisture index, proximity to trails, abundance of Umbellularia californica, and potential summer solar radiation. This research demonstrates the utility of integrating remotely sensed imagery analysis with geographic information systems and spatial modeling for understanding the dynamics of exotic species invasions. Numéro de notice : A2002-233 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : sans En ligne : https://www.asprs.org/wp-content/uploads/pers/2002journal/october/2002_oct_1001- [...] Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22147
in Photogrammetric Engineering & Remote Sensing, PERS > vol 68 n° 10 (October 2002) . - pp 1001 - 1009[article]Quantitative measures for spatial information of maps / Z. Li in International journal of geographical information science IJGIS, vol 16 n° 7 (october 2002)
[article]
Titre : Quantitative measures for spatial information of maps Type de document : Article/Communication Auteurs : Z. Li, Auteur ; P. Huang, Auteur Année de publication : 2002 Article en page(s) : pp 699 - 709 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie
[Termes IGN] distribution spatiale
[Termes IGN] graphe
[Termes IGN] indicateur de qualité
[Termes IGN] information cartographiqueRésumé : (Auteur) The map is a medium for recording geographical information. The information contents of a map are of interest to spatial information scientists. In this paper, existing quantitative measures for map information are evaluated. It is pointed out that these are only measures for statistical information and some sort of topological information. However, these measures have not taken into consideration the spaces occupied by map symbols and the spatial distribution of these symbols. As a result, a set of new quantitative measures is proposed, for metric information, topological information and thematic information. An experimental evaluation is also conducted. Results show that the metric information is more meaningful than statistical information, and the new index for topological information is more meaningful than the existing one. It is also found that the new measure for thematic information is useful in practice. Numéro de notice : A2002-213 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810210149416 En ligne : https://doi.org/10.1080/13658810210149416 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22128
in International journal of geographical information science IJGIS > vol 16 n° 7 (october 2002) . - pp 699 - 709[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-02071 RAB Revue Centre de documentation En réserve L003 Disponible A graphical method for exploring spatiotemporal point distributions / Yukio Sadahiro in Cartography and Geographic Information Science, vol 29 n° 2 (April 2002)PermalinkModelling a discrete spatial response using generalized linear mixed models: application to Lyme disease vectors / Abhik Das in International journal of geographical information science IJGIS, vol 16 n° 2 (march 2002)PermalinkL'analyse spatiale, volume 2. Les interactions spatiales / Denise Pumain (2001)PermalinkGroupement d'Intérêt Scientifique Sol (GIS Sol) : Partageons la connaissance des sols / Antonio Bispo (2001)PermalinkSatellite data for air pollution mapping over a city - virtual stations / A. Ung (2001)PermalinkSpatial and temporal distribution of atmospheric water vapor using space geodetic techniques / Lars Peter Kruse (2001)PermalinkDetermination of grid size for digital terrain modelling in landscape investigations: exemplified by soil moisture distribution at a micro-scale / Igor V. Florinsky in International journal of geographical information science IJGIS, vol 14 n° 8 (december 2000)PermalinkThe roles of meso objects for generalisation / Anne Ruas (2000)PermalinkAccessibilité et diffusion spatiale / Pierre Dumolard in Espace géographique, vol 28 n° 3 (octobre - décembre 1999)PermalinkGeophysical distributions of occultations of GPS satellites viewed from a low Earth orbiting satellite / D.M. O'Brien (1998)PermalinkL'analyse spatiale, Volume 1. Localisations dans l'espace / Denise Pumain (1997)PermalinkStatistique et territoire / J. Charre (1995)PermalinkFirst epoch geodetic GPS measurements across the Afar Plate Boundary Zone / Jean-Claude Ruegg in Geophysical research letters, vol 20 n° 18 (Septembre 1993)PermalinkGPS satellite sky distribution / Rock Santerre (1989)PermalinkModeling surface temperature distributions in forest landscapes / H.R. Holbo in Remote sensing of environment, vol 27 n° 1 (01/01/1989)PermalinkMise en oeuvre du modèle gamma pour l'estimation de distributions spatiales / Lin-Ying Hu (1988)PermalinkTowards the improvement of the dot map / R.E. Dahlberg in Annuaire international de cartographie, n° 7 (1967)Permalink