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Auteur E. Jeansou |
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Ajouter le résultat dans votre panier Affiner la recherche Interroger des sources externesCalibrating the Jason-1 measurement system: Initial initial results from the Corsica and harvest verification experiments / Pascal Bonnefond in Advances in space research, vol 32 n° 11 (December 2003)
Titre : Calibrating the Jason-1 measurement system: Initial initial results from the Corsica and harvest verification experiments Type de document : Article/Communication Auteurs : Pascal Bonnefond, Auteur ; G. Born, Auteur ; Pierre Exertier, Auteur ; S. Gill, Auteur ; G. Jans, Auteur ; E. Jeansou, Auteur ; D. Kubitschek, Auteur ; Olivier Laurain, Auteur ; Y. Menard, Auteur ; Alain Orsoni Année de publication : 2003 Article en page(s) : pp 2135 - 2140 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] altimètre radar
[Termes IGN] Corse
[Termes IGN] étalonnage d'instrumentRésumé : (auteur) We present calibration results from Jason-1 (2002-) and TOPEX/Poseidon (1992-) overflights of dedicated verification sites on the Mediterranean island of Corsica and on a California offshore oil platform (Harvest). Harvest served for a decade (1992–2002) as a calibration site for the TOPEX/Poseidon (T/P) mission, and is serving in a similar capacity for Jason-1. Initiated in 1996, the Corsica experiment features a fiducial reference station near Aspretto, and a primary sub-satellite tide-gauge deployment site 40 km south at Cape Senetosa. Both Corsica and Harvest feature carefully designed collocations of space-geodetic and tide-gauge systems to support the absolute calibration of the altimetric sea-surface height (SSH). Early estimates of the SSH bias from Harvest and Corsica are in excellent agreement, indicating that interim SSH measurements from Jason-1 were too high by +5 ± 1 cm (one standard error). By incorporating improved estimates of the Jason-1 sea-state bias and columnar atmospheric wet path delay, we observe a significant increase—to about 12 cm—in the SSH. Excepting the bias, the high accuracy of the Jason-1 measurements is in evidence from early overflights. In addition to providing important insight on the accuracy of the science data products during the validation phase of the mission, the estimates of the SSH bias and stability from Corsica, Harvest and other calibration programs will be used to link the T/P and Jason-1 sea-level records. Numéro de notice : A2003-459 Affiliation des auteurs : IGN+Ext (1940-2011) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/S0273-1177(03)90534-5 Date de publication en ligne : 13/02/2004 En ligne : https://doi.org/10.1016/S0273-1177(03)90534-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101128
in Advances in space research > vol 32 n° 11 (December 2003) . - pp 2135 - 2140[article]
Titre : Absolute calibration of Jason-1 and TOPEX/Poseidon altimeters in Corsica Type de document : Article/Communication Auteurs : Pascal Bonnefond, Auteur ; Pierre Exertier, Auteur ; Olivier Laurain, Auteur ; Y. Menard, Auteur ; Alain Orsoni Année de publication : 2003 Article en page(s) : pp 261 - 284 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] altimètre radar
[Termes IGN] bouée
[Termes IGN] Corse
[Termes IGN] erreur systématique
[Termes IGN] étalonnage d'instrument
[Termes IGN] orbite précise
[Termes IGN] source d'erreur
[Termes IGN] télémétrie laser sur satelliteRésumé : (auteur) The double geodetic Corsica site, which includes Ajaccio-Aspretto and Cape Senetosa (40 km south Ajaccio) in the western Mediterranean area, has been chosen to permit the absolute calibration of radar altimeters. It has been developed since 1998 at Cape Senetosa and, in addition to the use of classical tide gauges, a GPS buoy is deployed every 10 days under the satellites ground track (10 km off shore) since 2000. The 2002 absolute calibration campaign made from January to September in Corsica revealed the necessity of deploying different geodetic techniques on a dedicated site to reach an accuracy level of a few mm: in particular, the French Transportable Laser Ranging System (FTLRS) for accurate orbit determination, and various geodetic equipment as well as a local marine geoid, for monitoring the local sea level and mean sea level. TOPEX/Poseidon altimeter calibration has been performed from cycle 208 to 365 using M-GDR products, whereas Jason-1 altimeter calibration used cycles from 1 to 45 using I-GDR products. For Jason-1, improved estimates of sea-state bias and columnar atmospheric wet path delay as well as the most precise orbits available have been used. The goal of this article is to give synthetic results of the analysis of the different error sources for the tandem phase and for the whole studied period, as geophysical corrections, orbits and reference frame, sea level, and finally altimeter biases. Results are at the millimeter level when considering one year of continuous monitoring; they show a great consistency between both satellites with biases of 6 ± 3 mm (ALT-B) and 120 ± 7 mm, respectively, for TOPEX/Poseidon and Jason-1. Numéro de notice : A2003-460 Affiliation des auteurs : IGN+Ext (1940-2011) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/714044521 Date de publication en ligne : 21/06/2010 En ligne : https://doi.org/10.1080/714044521 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101125
in Marine geodesy > vol 26 n°3-4 (July - December 2003) . - pp 261 - 284[article]
Titre : Leveling the sea surface using a GPS-catamaran Type de document : Article/Communication Auteurs : Pascal Bonnefond, Auteur ; Pierre Exertier, Auteur ; Olivier Laurain, Auteur ; Y. Menard, Auteur ; Alain Orsoni Année de publication : 2003 Article en page(s) : pp 319 - 334 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie
[Termes IGN] géodésie marine
[Termes IGN] positionnement par GPSRésumé : (auteur) In the framework of the TOPEX/Poseidon and Jason-1 CNES-NASA missions, two probative experiments have been conducted at the Corsica absolute calibration site in order to determine the local marine geoid slope under the ascending TOPEX/Poseidon and Jason-1 ground track (No. 85). An improved determination of the geoid slope was needed to better extrapolate the offshore (open-ocean) altimetric data to on-shore tide-gauge locations. This in turn improves the overall precision of the calibration process. The first experiment, in 1998, used GPS buoys. Because the time required to cover the extended area with GPS buoys was thought to be prohibitive, we decided to build a catamaran with two GPS systems onboard. Tracked by a boat at a constant speed, this innovative system permitted us to cover an area of about 20 km long and 5.4 km wide centered on the satellites' ground track. Results from an experiment in 1999 show very good consistency between GPS receivers: filtered sea-surface height differences have a mean bias of −0.2 cm and a standard deviation of 1.2 cm. No systematic error or distortions have been observed and crossover differences have a mean value of 0.2 cm with a standard deviation of 2.7 cm. Comparisons with tide gauges data show a bias of 1.9 cm with a standard deviation of less than 0.5 cm. However, this bias, attributable in large part to the effect of the catamaran speed on the waterline, does not affect the geoid slope determination which is used in the altimeter calibration process. The GPS-deduced geoid slope was then incorporated in the altimeter calibration process, yielding a significant improvement (from 4.9 to 3.3 cm RMS) in the agreement of altimeter bias determinations from repeated overflight measurements. Numéro de notice : A2003-465 Affiliation des auteurs : IGN+Ext (1940-2011) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/714044524 En ligne : https://doi.org/10.1080/714044524 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101147
in Marine geodesy > vol 26 n°3-4 (July - December 2003) . - pp 319 - 334[article]
