Centre de documentation
scientifique

Elévation du niveau de la mer le long des côtes de France / C. Auger (1994)

Public Titre : Elévation du niveau de la mer le long des côtes de France : mesures, impacts, réponses Type de document : Actes de congrès Auteurs : C. Auger, Auteur Editeur : Paris : Ministère de l'Environnement Année de publication : 1994 Collection : Séminaire eaux, environnement num. 4 Conférence : Séminaire de travail Elévation du niveau de la mer, le long des côtes de France : mesures, impacts, réponses 06/12/1993 07/12/1993 Paris France Importance : 311 p. Format : 23 x 30 cm Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Océanographie [Termes IGN] aménagement [Termes IGN] érosion côtière [Termes IGN] géodésie spatiale [Termes IGN] marée terrestre [Termes IGN] marégraphie [Termes IGN] mer [Termes IGN] montée du niveau de la mer [Termes IGN] niveau moyen des mers [Termes IGN] perturbation séculaire Numéro de notice : 64963 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Actes Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=36422

Contient

• Les techniques de géodésie spatiale / Claude Boucher (06/12/1993)
• Les techniques de nivellements / Paul Bonnetain (06/12/1993)
• Mesures des variations du niveau de la mer / Claude Boucher (06/12/1993)

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
64963-01	CG.93	Livre	Centre de documentation	Congrès	Disponible

Estimation of sea dynamic topography, ocean tides, and secular changes from Topex altimeter data / Y.M. Wang (1994)

Public Titre : Estimation of sea dynamic topography, ocean tides, and secular changes from Topex altimeter data Type de document : Monographie Auteurs : Y.M. Wang, Auteur ; R.H. Rapp, Auteur Editeur : Colombus (Ohio) : Ohio State University Année de publication : 1994 Collection : Department of Geodetic Science and Surveying Reports num. 430 Importance : 86 p. Format : 21 x 27 cm Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale [Termes IGN] données altimétriques [Termes IGN] fonction harmonique [Termes IGN] harmonique sphérique [Termes IGN] hauteurs de mer [Termes IGN] marée océanique [Termes IGN] perturbation séculaire [Termes IGN] TOPEX [Termes IGN] valeur efficace Index. décimale : 30.52 Marégraphie et niveau moyen des mers Résumé : (Auteur) Sea surface dynamic topography (SSDT) has been determined from the separation of the Topex sea surface height and the geoid undulations implied by the JGM-2/OSU91A merged potential coefficient model. The SSDT was initially analyzed to determine annual and semiannual variations in the ocean surface, corrections to the M2, S2, K1, 01 constituents of the Cartwright/Ray tide model, and bias and bias rate terms. All correction terms were represented by spherical series to degree 8 (for most testing purposes) and to degree 15 for final runs. The most complete analysis was done with Topex cycles 4 to 58. From this solution we found that the root mean square annual signal was ±4.5 cm in the Northern Hemisphere and ±3.5 cm in the Southern Hemisphere with an overall amplitude of ±4.0 cm. Large 'annual signals were associated with features such as the Kurishio Current (±10 cm), Gulf Stream (±7 cm) and the Falkland Current (±6 cm). The tide correction terms were ±2.9 CM (MA ±1.5 CM (S2), +0.8 CM (01), ±1.4 cm. (K1). The improvement in the tide model was proven through comparisons at the 104/95 tide gauge data set provided by C. Le Provost. The bias rate value was determined at each normal point and then averaged to determine a mean rate of 4.8 mm/yr. - After removing an altimeter drift rate of 2.0 mm/yr the net rate is 2.8 mm/yr., This rate could be a combination of sea level change and effects associated with the various correction terms applied to the data. The second main theme of the report relates to the representation of SSDT in spherical harmonics (SH) and orthonormal (ON) functions. Procedures were implemented to estimate either SH or ON coefficients. It was found that the estimation of SH coefficients was more stable than the ON estimation. For those applications on which spectral information of SSDT is needed a SH model can be transformed into an ON model. It was found that the lower degree SH coefficients are quite sensitive to the -bias correction applied to the sea surface height data. This sensitivity does not occur in ON coefficient estimation. For the analysis with data from cycles 4 to 58 a bias term of 55 cm. was applied to the data. This value leads to a zero value for the degree zero term in the ON expansion. An SH expansion to degree 24 was computed using a priori degree variance computed from 10 selected cycles of Topex data. The SH expansion was transformed to an ON expansion and both coefficient sets are given in the report. The degree 2,0 coefficient in the SH representation was -37.8 cm quite comparable with other altimeter based solutions. The analysis of the ON coefficient indicated an rms value of SSDT equal to ±61 cm. The ON- power spectrum, in conjunction with the geoid undulation accuracy of the JGM-2 model in the ocean areas, indicated the two values are approximately equal near degree 13. This suggests that SSDT estimates above degree 13 may be unreliable. This statement was consistent with the inconsistency of geostrophic flow patterns implied, by the SSDT expansions at the higher degrees. Even at the lower (e.g. 13) degree the flow patterns showed only moderate agreement with known circulation patterns. Numéro de notice : 12110 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54539

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
12110-01	30.52	Livre	Centre de documentation	Géodésie	Disponible