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Assessment of long-range kinematic GPS positioning errors by comparison with airborne laser altimetry and satellite altimetry / X. Zhang in Journal of geodesy, vol 81 n° 3 (March 2007)
[article]
Titre : Assessment of long-range kinematic GPS positioning errors by comparison with airborne laser altimetry and satellite altimetry Type de document : Article/Communication Auteurs : X. Zhang, Auteur ; René Forsberg, Auteur Année de publication : 2007 Article en page(s) : pp 201 - 211 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] altimétrie satellitaire par radar
[Termes IGN] analyse comparative
[Termes IGN] Atlantique Nord
[Termes IGN] glace de mer
[Termes IGN] GPS en mode cinématique
[Termes IGN] Groenland
[Termes IGN] positionnement ponctuel précis
[Termes IGN] précision décimétrique
[Termes IGN] télémétrie laser aéroportéRésumé : (Auteur) Long-range airborne laser altimetry and laser scanning (LIDAR) or airborne gravity surveys in, for example, polar or oceanic areas require airborne kinematic GPS baselines of many hundreds of kilometers in length. In such instances, with the complications of ionospheric biases, it can be a real challenge for traditional differential kinematic GPS software to obtain reasonable solutions. In this paper, we will describe attempts to validate an implementation of the precise point positioning (PPP) technique on an aircraft without the use of a local GPS reference station. We will compare PPP solutions with other conventional GPS solutions, as well as with independent data by comparison of airborne laser data with “ground truth” heights. The comparisons involve two flights: A July 5, 2003, airborne laser flight line across the North Atlantic from Iceland to Scotland, and a May 24, 2004, flight in an area of the Arctic Ocean north of Greenland, near-coincident in time and space with the ICESat satellite laser altimeter. Both of these flights were more than 800 km long. Comparisons between different GPS methods and four different software packages do not suggest a clear preference for any one, with the heights generally showing decimeter-level agreement. For the comparison with the independent ICESat- and LIDAR-derived “ground truth” of ocean or sea-ice heights, the statistics of comparison show a typical fit of around 10 cm RMS in the North Atlantic, and 30 cm in the sea-ice region north of Greenland. Part of the latter 30 cm error is likely due to errors in the airborne LIDAR measurement and calibration, as well as errors in the “ground truth” ocean surfaces due to drifting sea-ice. Nevertheless, the potential of the PPP method for generating 10 cm level kinematic height positioning over long baselines is illustrated. Numéro de notice : A2007-184 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-006-0100-6 En ligne : https://doi.org/10.1007/s00190-006-0100-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28547
in Journal of geodesy > vol 81 n° 3 (March 2007) . - pp 201 - 211[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-07031 RAB Revue Centre de documentation En réserve L003 Disponible 266-07032 RAB Revue Centre de documentation En réserve L003 Disponible Sea ice monitoring by L-band SAR: an assessment based on literature and comparisons of JERS-1 and ERS-1 imagery / W. Dierking in IEEE Transactions on geoscience and remote sensing, vol 44 n° 4 (April 2006)
[article]
Titre : Sea ice monitoring by L-band SAR: an assessment based on literature and comparisons of JERS-1 and ERS-1 imagery Type de document : Article/Communication Auteurs : W. Dierking, Auteur ; T. Busche, Auteur Année de publication : 2006 Article en page(s) : pp 957 - 970 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] analyse diachronique
[Termes IGN] angle d'incidence
[Termes IGN] Arctique
[Termes IGN] bande L
[Termes IGN] diffusomètre
[Termes IGN] glace de mer
[Termes IGN] Groenland
[Termes IGN] image ERS-SAR
[Termes IGN] image JERS
[Termes IGN] polarisation
[Termes IGN] surveillance hydrologique
[Termes IGN] Svalbard
[Termes IGN] zone polaireRésumé : (Auteur) Spaceborne single-polarization C-band synthetic aperture radar (SAR) imagery is widely used to gather information about the state of the sea ice cover in the polar regions. C-band is regarded as a reasonable choice for all-season monitoring capabilities. For specific mapping tasks, however, other frequency hands can be more suitable. In the first part of this paper, the summary of a literature study dealing with the utilization of L-band SAR imagery for sea ice monitoring is presented. Investigations reveal that if deformation features such as ice ridges, rubble fields, and brash ice are to be mapped, L-band radar is superior in a number of cases. The second part of this paper addresses the comparison of JERS-1 and ERS-1 SAR images that were acquired over sea ice east of Svalbard and along the east coast of Greenland. The effects of the different frequencies, polarizations, and incidence angles of the two SAR Systems are discussed. It is demonstrated that the images of both sensors complement one another in the analysis of ice conditions, resulting in a more detailed view of the sea ice cover state. Copyright IEEE Numéro de notice : A2006-211 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2005.861745 En ligne : https://doi.org/10.1109/TGRS.2005.861745 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27938
in IEEE Transactions on geoscience and remote sensing > vol 44 n° 4 (April 2006) . - pp 957 - 970[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-06041 RAB Revue Centre de documentation En réserve L003 Disponible
[article]
Titre : Cryosat: a mission to the ice fields of Earth Type de document : Article/Communication Auteurs : D. Wingham, Auteur Année de publication : 2005 Article en page(s) : pp 11 - 25 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Technologies spatiales
[Termes IGN] altimètre radar
[Termes IGN] Antarctique
[Termes IGN] Arctique, océan
[Termes IGN] changement climatique
[Termes IGN] Cryosat
[Termes IGN] glace
[Termes IGN] Groenland
[Termes IGN] mission spatiale
[Termes IGN] morphologie glaciaire
[Termes IGN] satellite d'observation de la TerreRésumé : (Auteur) The accurate prediction and observation of the ice masses at the poles, and particularly of their rates of change, is of interest to us all, not least because 5% of the Earth's population live just 1 meter above sea level. Native Arctic populations face profound changes to their way of life and even existence. Economic interest, associated with oil and gas and trans-Artic shipping, will grow as the pack ice declines, as too may strategic concerns over the sovereignty of the Arctic Ocean. The loss of pack ice may also affect the circulation of the Atlantic, and with it winter weather of western Europe. CryoSat is ESA's first mission dedicated to the observation of the Earth's polar ice masses. Its goals are to determine if there is indeed a downward trend in the mass of artic sea ice, and wether we should regard Antarctica as under threat from global warming. Numéro de notice : A2005-275 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Article DOI : sans En ligne : http://www.esa.int/esapub/bulletin/bulletin122/bul122b_wingham.pdf Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27411
in ESA bulletin > n° 122 (May 2005) . - pp 11 - 25[article]Blowing in the wind / G. Giebel in GEO: Geoconnexion international, vol 4 n° 4 (april 2005)
[article]
Titre : Blowing in the wind Type de document : Article/Communication Auteurs : G. Giebel, Auteur Année de publication : 2005 Article en page(s) : pp 42 - 44 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] Danemark
[Termes IGN] développement durable
[Termes IGN] énergie éolienne
[Termes IGN] géomorphologie locale
[Termes IGN] recherche et développement
[Termes IGN] système d'information géographiqueRésumé : (Auteur) Gis tools are playing an important role in the growing wind energy industry. That role is being investigated at one of the worlds largest wind research facilities in Denmark. Numéro de notice : A2005-142 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27280
in GEO: Geoconnexion international > vol 4 n° 4 (april 2005) . - pp 42 - 44[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 062-05041 RAB Revue Centre de documentation Revues en salle Disponible Regional simulation of ecosystem CO2 and water vapor exchange for agricultural land using NOAA AVHRR and Terra MODIS satellite data: Application to Zealand, Denmark / Rasmus M. Houborg in Remote sensing of environment, vol 93 n° 1 (30/10/2004)
[article]
Titre : Regional simulation of ecosystem CO2 and water vapor exchange for agricultural land using NOAA AVHRR and Terra MODIS satellite data: Application to Zealand, Denmark Type de document : Article/Communication Auteurs : Rasmus M. Houborg, Auteur ; H. Soegaard, Auteur Année de publication : 2004 Article en page(s) : pp 150 - 167 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] agriculture
[Termes IGN] atmosphère terrestre
[Termes IGN] couvert végétal
[Termes IGN] covariance
[Termes IGN] Danemark
[Termes IGN] dioxyde de carbone
[Termes IGN] flux
[Termes IGN] Green Leaf Area Index
[Termes IGN] image NOAA-AVHRR
[Termes IGN] image Terra-MODIS
[Termes IGN] indice de végétation
[Termes IGN] nuage
[Termes IGN] turbulence
[Termes IGN] vapeur d'eauRésumé : (Auteur) While accurate information on ecosystem C02 and water vapor exchange is available at eddy covariance flux tower sites, method, methods to expand predictions of C02 and energy exchange to regional or global scales with high fidelity are lacking. The main objective of this study was to examine the applicability of land surface and atmospheric products from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Advanced Very High Resolution Radiometer (AVHRR) for assessing the spatial variation in C02 and water vapor fluxes for cloudless agricultural land pixels at the Island of Zealand, Denmark. The spatial distribution of green leaf area index, directbeam ark: diffuse solar radiation and air humidity was inferred on the basis of late morning MODIS data that was combined with afternoon AVHRR data to resolve the diurnal variation in air and surface temperature. These variables were used in a coupled "twoleaf' ecosystem model operating at an hourly time scale. The enhanced vegetation index (EVI) was strongly correlated with field measurements of green leaf area index (r2=0.91) and remained sensitive to variations in green biomass up to green leaf area indices of 45. Evaluation against standard meteorological data showed that instantaneous estimates of air temperature, actual vapor pressure and incoming solar radiation could be retrieved with overall root mean square errors of 2.5°C, 138.3 Pa and 47.7 Wm2, respectively. The combination of late morning and afternoon inferences made it possible to resolve the diurnal course in key model parameters, and predicted rates of ecosystem C02 and water vapor exchange were comparable to eddy covariance measurements at a single flux tower. A large spatial diversity in C02 and water vapor exchange was maintained throughout the study period due to significant regional variations in meteorological input variables and large spatial differences in canopy development. The results of this study stress the necessity of pixel based estimates for an accurate evaluation of regional budgets of C02 and water vapor exchange. Numéro de notice : A2004-426 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2004.07.001 En ligne : https://doi.org/10.1016/j.rse.2004.07.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26953
in Remote sensing of environment > vol 93 n° 1 (30/10/2004) . - pp 150 - 167[article]Combining weather prediction and remote sensing data for the calculation of evapotranspiration rates: application to Denmark / E. Boegh in International Journal of Remote Sensing IJRS, vol 25 n° 13 (July 2004)PermalinkAutomated change detection for updates of digital map databases / T. Knudsen in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 11 (November 2003)PermalinkGeo-engineering in planning and design of roads: an example of Denmark / K. Van Der Lei in Geoinformatics, vol 5 n° 4 (01/06/2002)PermalinkGeneralisation at the Danish mapping agency / R. Sheehan in GIM international, vol 15 n° 7 (July 2001)PermalinkPermalinkTopographie des calottes glaciaires par altimétrie satellite / F. Remy in XYZ, n° 83 (juin - août 2000)PermalinkComparison of national guidelines for technical and cadastral mapping in Europe ("Ferrara test") / S. Dequal (01/09/1999)PermalinkMap generalisation in the nordic countries / T. Kilpelainen (1999)PermalinkSoil resources of Europe / P. Bullock (1999)PermalinkThe Oresund link: bridging the gap between Danemark and Sweden with RTK GPS / P. Norgard in GPS world, vol 9 n° 10 (October 1998)PermalinkIntegration of satellite data in local geodetic networks / K. Engsager (1998)PermalinkFramework for the world / David Rhind (1997)PermalinkDie Weiterführung der geodätischen Arbeiten der Internationalen glaziologischen Grönland-Expedition (EGIG) durch das Institut für Vermessungskunde der TU Braunschweig 1987-1993 / C. Homann (1996)PermalinkGIS diffusion / Ian Masser (1996)PermalinkGravity and GPS survey on the summit of the Greenland ice sheet 1991-1992 / S. Ekholm (1993)PermalinkFrom Mars to Greenland / O. Colombo (1992)Permalink[Dossier de la] 9ème Assemblée générale de l'Association Cartographique Internationale / International cartographic association = association cartographique internationale (1991)PermalinkA shipborne AVHRR-HRPT receiving and image processing system for polar research / T. Viehoff in International Journal of Remote Sensing IJRS, vol 11 n° 5 (May 1990)PermalinkComparison of in situ and satellite-derived reflectances of Forbindels glacier, Greenland / D.K. Hall in International Journal of Remote Sensing IJRS, vol 11 n° 3 (March 1990)PermalinkA multisensor approach to sea ice classification for the validation of DMSP-SSM-I passive microwave derived sea ice products / K. Steffen in Photogrammetric Engineering & Remote Sensing, PERS, vol 56 n° 1 (january 1990)Permalink