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GPS water vapor project associated to the ESCOMPTE programme: description and first results of the field experiment / Olivier Bock in Physics and chemistry of the Earth (A/B/C), vol 29 n° 2-3 ([01/03/2004])
[article]
Titre : GPS water vapor project associated to the ESCOMPTE programme: description and first results of the field experiment Type de document : Article/Communication Auteurs : Olivier Bock , Auteur ; Erik Doerflinger, Auteur ; F. Masson, Auteur ; Andrea Walpersdorf, Auteur ; J. Van-Baelen, Auteur ; Jérôme Tarniewicz , Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 149 - 157 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] analyse comparative
[Termes IGN] lidar Raman
[Termes IGN] radiosondage
[Termes IGN] tomographie par GPS
[Termes IGN] vapeur d'eauRésumé : (auteur) A dense network of 17 dual frequency GPS receivers has been operated for two weeks during June 2001 within a 20 km × 20 km area around Marseille, France, as part of the ESCOMPTE field campaign ([Cros et al., 2004. The ESCOMPTE program: an overview. Atmos. Res. 69, 241–279]; http://medias.obs-mip.fr/escompte). The goal of this GPS experiment was to provide GPS data allowing for tomographic inversions and their validation within a well-documented observing period (the ESCOMPTE campaign). Simultaneous water vapor radiometer, solar spectrometer, Raman lidar and radiosonde data are used for comparison and validation. In this paper, we highlight the motivation, issues and describe the GPS field experiment. Some first results of integrated water vapor retrievals from GPS and the other sensing techniques are presented. The strategies for GPS data processing and tomographic inversions are discussed. Numéro de notice : A2004-490 Affiliation des auteurs : IGN+Ext (1940-2011) Thématique : POSITIONNEMENT Nature : Article DOI : 10.1016/j.pce.2004.01.014 En ligne : https://doi.org/10.1016/j.pce.2004.01.014 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103037
in Physics and chemistry of the Earth (A/B/C) > vol 29 n° 2-3 [01/03/2004] . - pp 149 - 157[article]Atmosphärische und ozeanische Einflüsse auf die Rotation der Erde - Nummerische Untersuchungen mit einem dynamischen Erdsystemmodell / Florian Seitz (2004)
Titre : Atmosphärische und ozeanische Einflüsse auf die Rotation der Erde - Nummerische Untersuchungen mit einem dynamischen Erdsystemmodell Titre original : [Influences atmosphérique et océanographique sur la rotation de la Terre : études numériques avec un modèle dynamique systémique de la Terre] Type de document : Thèse/HDR Auteurs : Florian Seitz, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2004 Collection : DGK - C Sous-collection : Dissertationen num. 578 Importance : 94 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-5017-4 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] atmosphère terrestre
[Termes IGN] circulation atmosphérique
[Termes IGN] circulation océanique
[Termes IGN] marée terrestre
[Termes IGN] modèle dynamique
[Termes IGN] moment cinétique atmosphérique
[Termes IGN] mouvement du pôle
[Termes IGN] océan
[Termes IGN] ondelette
[Termes IGN] rotation de la Terre
[Termes IGN] terme de Chandler
[Termes IGN] théorème de LiouvilleIndex. décimale : 30.40 Géodésie physique Résumé : (Auteur) Variations of Earth rotation are caused by a multitude of gravitational and geophysical processes in the Earth system. The largest effects are due to tidal deformations of the solid Earth and mass redistributions within the atmosphere and the oceans. In order to study the Earth's reaction on gravitational and geophysical excitations, the dynamic Earth system model DyMEG has been developed. It is based on the balance of angular momentum in the Earth system, which is described by the non-linear Liouville equation. The model is forced by consistent time series of variations of the Earth's tensor of inertia and relative angular momenta which are deduced from atmospheric and oceanic circulation models. In contrast to former investigations, the characteristics of the Earth's free polar motion (Chandler wobble) are not explicitly predetermined with respect to period and damping but reproduced by the model from geometrical and rheological parameters. Therefore the traditional analytical solution is not applicable, and the Liouville equation is solved numerically as an initial value problem. A sensitivity analysis of DyMEG reveals that the solution based on a Runge-Kutta method is reliable from an algorithmic point of view. However, the system is sensitive to the initial conditions of the integration and the rheological model parameters (Love numbers). Forced variations of Earth rotation due to atmospheric and oceanic excitations yield an effect on the free polar motion as rotational deformations of the solid Earth are regarded in DyMEG. Wavelet analyses of the resulting time series for polar motion show that the Chandler wobble from DyMEG is excited by the atmospheric and oceanic mass redistributions over more than two decades. The noise of the excitation series is found to contain sufficient energy to counteract the damping of the Chandler amplitude which is caused by friction. It is assumed that the noise is due to stochastic processes within the atmosphere (weather). The numerical results for polar motion and length-of-day variations from DyMEG are significantly related with geodetic observations. Depending on the quality of the excitations, the correlation coefficients between the model time series and observations amount to 0,99. In addition to the rotational variations, time series of the second degree spherical harmonic coefficients of the Earth's gravity field, which are directly linked to the tensor of inertia, are computed. The mean values of the respective coefficients are in good agreement with recent gravity models. However the validation of their temporal variations is limited as suitable observation time series are not yet available. Numéro de notice : 13278 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54957 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 13278-01 30.40 Livre Centre de documentation Géodésie Disponible Expert systems and Geographic Information Systems for impact assessment / A. Rodriguez-Bachiller (2004)
Titre : Expert systems and Geographic Information Systems for impact assessment Type de document : Monographie Auteurs : A. Rodriguez-Bachiller, Auteur Editeur : Londres : Taylor & Francis Année de publication : 2004 Importance : 399 p. Format : 15 x 24 cm ISBN/ISSN/EAN : 978-0-415-30725-3 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes d'information géographique
[Termes IGN] atmosphère terrestre
[Termes IGN] bruit (audition)
[Termes IGN] eau
[Termes IGN] écologie
[Termes IGN] environnement
[Termes IGN] étude d'impact
[Termes IGN] impact sur l'environnement
[Termes IGN] pollution
[Termes IGN] système d'information géographique
[Termes IGN] système expertRésumé : (Editeur) This book is becoming part of an increasing number of development proposals in the UK and Europe. As the practice of Impact Assessment develops, it is becoming more standardised and good practice is starting to be defined. However, its quality is still far from satisfactory. Expert Systems and Geographic information Systems for Impact Assessment discusses the potential for integrating these two well known computer technologies to help with the process of Impact Assessment. The proposition behind the work is that all three areas are potentially complementary and that mutual benefits can be gained from bringing them together in the field of planning. Following an introduction to each area, the various ways in which GIS and Expert Systems can be applied are discussed. Note de contenu : PART I - GIS AND EXPERT SYSTEMS FOR IMPACT ASSESSMENT
1 The potential of expert systems and GIS for impact assessment
2 Expert systems and decision support
3 GIS and impact assessment
4 GIS and environmental management
5 GIS and expert systems for impact assessment
PART II - BUILDING EXPERT SYSTEMS (WITH AND WITHOUT GIS) FOR IMPACT ASSESSMENT
6 Project screening and scoping
7 Hard-modelled impacts: air and noise
8 Soft-modelled impacts: terrestrial ecology and landscape
9 Socio-economic and traffic impacts
10 Water impacts
11 Reviewing environmental impact statements
12 Conclusions: the limits of GIS and expert systems for impact assessmentNuméro de notice : 18848 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Monographie Accessibilité hors numérique : Accessible via le SUDOC (sur demande au cdos) Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=55489 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 Exemplaires(2)
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 Optical remote sensing / W.G. Egan (2004)
Titre : Optical remote sensing : science and technology Type de document : Monographie Auteurs : W.G. Egan, Auteur Editeur : New York : Marcel Dekker, Inc. Année de publication : 2004 Importance : 507 p. Format : 15 x 23 cm ISBN/ISSN/EAN : 978-0-8247-4131-0 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Télédétection
[Termes IGN] aérosol
[Termes IGN] analyse de données
[Termes IGN] atmosphère stellaire
[Termes IGN] effet atmosphérique
[Termes IGN] formule de Stokes
[Termes IGN] image optique
[Termes IGN] Mars (planète)
[Termes IGN] mer
[Termes IGN] photométrie
[Termes IGN] planète
[Termes IGN] polarisation
[Termes IGN] rayonnement ultraviolet
[Termes IGN] réflectance
[Termes IGN] réfraction
[Termes IGN] transfert radiatifIndex. décimale : 35.00 Télédétection - généralités Résumé : (Auteur) Written by a pioneer in the field, this unique volume explores advanced concepts in the mathematical representation of polarization, descriptors, and various optical elements used in the analysis of polarization in multiple applications-high tried and proven techniques to enhance aircraft and satellite technology and determine the photometric and polarimetric properties of atmosphere, ground surfaces, and inner and outer space. Optical Remote Sensing contemplates the applications of this technology in the study of the air, sea, sky, and stars ... the optical detection of terrorism ... military defense ... homeland security ... aircraft design ... mathematical modeling ... Fourier transform spectroscopy ... and land and sea polarization, and considers the detection and measurement of polarized radiation ... instrument specification ... data acquisition, storage, and analysis ... polarization and surface roughness ... planetary surface study and remote sensing ... ultraviolet spectra of organic molecules and the interstellar medium ... optical properties of continental haze and cumulus clouds ... volumetric scattering and absorption by aerosols ... optical enhancement of aircraft, vehicle, and personnel detection through polarization ... population and vehicle movement ... optical complex indices of refraction ... the monitoring of the Earth's resources ... the characterization of commodity futures from worldwide crop production ... plant disease concentration patterns ... water quality determination ... earthquake and climate prediction ... stellar infrared optics ... and the spread of AIDS in Africa by tracing decreases in crop production. Note de contenu : 1. Polarization and Remote Sensing
2. Photometry
3. Polarization
4. Stokes Parameters
5. Instrumentation
6. Data Acquisition and Storage
7. Data Analysis
8. Polarization and Surface Roughness
9. Polarized Laser Retroreflectance
10. Remote Sensing of Seismic Disturbances
11. High-Resolution Space Shuttle Polarimetry for Farm Crop Classification
12. Planetary Remote Sensing Atmospheres
13. Effect of Aerosols on Optical Remotely Sensed Data
14. Comparison Between Infrared Martian Disk Spectra and Optical Properties of Terrestrial Analogs
15. The Interstellar Medium: Ultraviolet Complex Index of Refraction of Several Candidate Materials
16. Anomalous Refractive Index of SubmicrometerSized Particulates
17. Ultraviolet Spectra of Organic Molecules and the Interstellar Medium
18. Complex Index of Refraction of Bulk Solid Carbon Dioxide
19. Star Environments
20. Optical Properties of Continental Haze and Cumulus and Orographic Clouds Based on Space Shuttle
Polarimetric Observations
21. Volumetric Scattering and Absorption by Aerosols: Parametric Sensitivity in Mie Modeling and
Comparisons to Observations
22. Radiative Transfer Properties of the Sahara Region
23. Meteorological Analysis of Chemical Exchange Events in the Arctic Basin
24. Optical Enhancement of Aircraft Detection Using Polarization
25. Detection of Vehicles and Personnel Using Polarization
26. Optical Remote Sensing of the Sea: A Caribbean Example
27. Phvsical Variation of Water Vapor and the Relation with Carbon Dioxide
28. Oil Spill Analysis
29. Infrared Optical Constants of Sahara Sand, Volcanic Ash, and Water-Soluble Aerosols
30. Optical Properties of Standard Aerosols
31. Polarization Modeling Using MODTRAN 3.7Numéro de notice : 16439 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=55162 La recherche scientifique spatiale en France, Rapport 2004 au Cospar, Comité Mondial de la Recherche Spatiale, 35e assemblée scientifique, 18-25 juillet 2004 / Yves d' Escatha (2004)PermalinkRemote sensing in transition / Rudi Goossens (2004)PermalinkRemote sensing of atmospheric water vapor with the Global Positioning System / John Joseph Braun (2004)PermalinkPermalinkFully polarimetric airborne SAR and ERS SAR observations of snow: implications for selection of Envisat ASAR modes / T. Guneriussen in International Journal of Remote Sensing IJRS, vol 24 n° 19 (October 2003)PermalinkRetrieval of atmospheric water vapour using a ground-based single-channel microwave radiometer / P. Jarlemark in International Journal of Remote Sensing IJRS, vol 24 n° 19 (October 2003)PermalinkAirborne forest fire mapping with an adaptive infrared sensor / D. Oertel in International Journal of Remote Sensing IJRS, vol 24 n° 18 (September 2003)PermalinkOptimizing a network-based RTK method for OTF [on-the-fly] positioning / L.P. Fortes in GPS solutions, vol 7 n° 2 (August 2003)PermalinkAnalysis of hyperspectral data for estimation of temperate forest canopy nitrogen concentration: Comparison between an Airborne (AVIRIS) and a spaceborne (Hyperion) sensor / M.L. Smith in IEEE Transactions on geoscience and remote sensing, vol 41 n° 6 (June 2003)PermalinkMonitoring the ionosphere with GPS: space weather / Anthea Coster in GPS world, vol 14 n° 5 (May 2003)Permalink