Descripteur
Termes IGN > altimétrie > niveau moyen des mers
niveau moyen des mersSynonyme(s)niveau moyen de la mer MSLVoir aussi |
Documents disponibles dans cette catégorie (143)
Ajouter le résultat dans votre panier
Visionner les documents numériques
Affiner la recherche Interroger des sources externes
Etendre la recherche sur niveau(x) vers le bas
L'élévation du niveau de la mer et les espaces côtiers / R. Paskoff (2001)
Titre : L'élévation du niveau de la mer et les espaces côtiers : le mythe et la réalité Type de document : Monographie Auteurs : R. Paskoff, Auteur Editeur : Paris : Institut Océanographique Année de publication : 2001 Collection : Propos, ISSN 1269-7435 Importance : 190 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-2-903581-27-5 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géomorphologie
[Termes IGN] delta
[Termes IGN] dune
[Termes IGN] effet de serre
[Termes IGN] estuaire
[Termes IGN] falaise
[Termes IGN] lagune
[Termes IGN] littoral
[Termes IGN] marais
[Termes IGN] niveau de la mer
[Termes IGN] niveau moyen des mers
[Termes IGN] plage
[Termes IGN] risque naturelRésumé : (Editeur) L'auteur fait le point sur les problèmes que pose la perspective d'une élévation du niveau planétaire de la mer dans les prochaines décennies, si le réchauffement de l'atmosphère, attendu de l'effet de serre lié aux activités humaines, devait se confirmer. Il étudie le comportement du niveau marin au cours des cent dernières années et celui prévu pour le 21ème siècle, sur la base des plus récentes estimations du groupe intergouvernemental pour l'évolution du climat. Celles-ci indiquent une tendance à la hausse qui devrait s'accélérer. Inondation, érosion et salinisation sont les conséquences attendues de cette hausse sur différents types d'espaces côtiers : falaises, plages et dunes, marais maritimes, mangroves, récifs coralliens, estuaires, deltas et lagunes. A ces phénomènes, les sociétés se doivent de trouver les réponses adéquates : convient-il de résister ou au contraire de s'adapter, en reculant devant l'avancée de la mer ? Numéro de notice : 13019 Affiliation des auteurs : non IGN Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54851 Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 13019-01 47.20 Livre Centre de documentation Géographie - Géosciences Disponible La douzième réunion technique internationale de la division des satellites de l'Institut de navigation, Nashville (Tennessee), Septembre 1999 [Compte-rendu du congrès] / Claude Million in XYZ, n° 84 (septembre - novembre 2000)
[article]
Titre : La douzième réunion technique internationale de la division des satellites de l'Institut de navigation, Nashville (Tennessee), Septembre 1999 [Compte-rendu du congrès] Type de document : Article/Communication Auteurs : Claude Million, Auteur Année de publication : 2000 Article en page(s) : pp 46 - 55 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] Global Navigation Satellite System
[Termes IGN] Global Orbitography Navigation Satellite System
[Termes IGN] Global Positioning System
[Termes IGN] niveau moyen des mers
[Termes IGN] temps réelNuméro de notice : A2000-217 Affiliation des auteurs : IGN (1940-2011) Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=21632
in XYZ > n° 84 (septembre - novembre 2000) . - pp 46 - 55[article]Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 112-00031 RAB Revue Centre de documentation En réserve L003 Disponible Geodesy beyond 2000 / K.P. Schwarz (2000)
Titre : Geodesy beyond 2000 : the challenge of the first decade, 35th IAG general assembly Type de document : Actes de congrès Auteurs : K.P. Schwarz, Auteur Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2000 Collection : International Association of Geodesy Symposia, ISSN 0939-9585 num. 121 Conférence : IAG 1999, 35th general assembly, Geodesy beyond 2000 : the challenge of the first decade 19/07/1999 30/07/1999 Birmingham Royaume-Uni Importance : 445 p. Format : 20 x 27 cm ISBN/ISSN/EAN : 978-3-540-67002-5 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie
[Termes IGN] géodynamique
[Termes IGN] géoréférencement
[Termes IGN] Global Orbitography Navigation Satellite System
[Termes IGN] Global Positioning System
[Termes IGN] GOCE
[Termes IGN] GRACE
[Termes IGN] marée terrestre
[Termes IGN] niveau moyen des mers
[Termes IGN] orbitographie
[Termes IGN] pesanteur terrestre
[Termes IGN] positionnement cinématiqueNuméro de notice : 68002 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Actes Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=37189 Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 68002-01 CG.99 Livre Centre de documentation Congrès Disponible The influence of data quality on the detectability of sea-level height variations / K.I. Van Onselen (2000)
Titre : The influence of data quality on the detectability of sea-level height variations Type de document : Monographie Auteurs : K.I. Van Onselen, Auteur Editeur : Delft : Netherlands Geodetic Commission NGC Année de publication : 2000 Collection : Netherlands Geodetic Commission Publications on Geodesy Sous-collection : New series num. 49 Importance : 204 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-90-6132-273-3 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] marée océanique
[Termes IGN] marégramme
[Termes IGN] marégraphe
[Termes IGN] niveau de la mer
[Termes IGN] niveau moyen des mers
[Termes IGN] qualité des données
[Termes IGN] série temporelle
[Termes IGN] variation
[Vedettes matières IGN] AltimétrieIndex. décimale : 30.50 Nivellement - généralités Résumé : (Auteur) For low-lying areas like the Netherlands, an over-increasing sea level can become a serious threat. This is especially true if sea level rise accelerates, e.g., due to greenhouse-gas induced warming. To anticipate potential troubles, it is important to have a good estimate of the expected behaviour of future sea levels. This requires an accurate description of the present-day sea level variation curve and of foreseeable changes in this "natural" pattern in the near future. These changes in the behaviour of future sea levels can be based, e.g., on models predicting global change, but this is beyond the scope of this thesis. Much simplified, sea level rise over the last century could be described by a linear regression line. Accelerations of this "natural" pattern have occurred if the slope value of the regression line increases, or higher order regression coefficients are required to describe the sea-level rise curve. The better the natural sea level variation curve (as has occurred over the last century) can be determined, the easier it will be to detect a significant divergence from this curve. The objective of this thesis is to determine how well patterns in sea level height variations can be detected, given the limited quality of the data available. The objective of this thesis requires long sea level height time series. Therefore, only tide gauge data has been used and altimetry sea level height series have not been considered. Tide gauges measure sea level heights relative to the tide gauge bench marks. Consequently, the resulting sea level height time series show both variations in absolute sea level and vertical movements of the tide gauge bench marks. By monitoring the height changes between the tide gauge bench marks and a stable reference height, these relative sea level heights can (in principle) be converted into absolute sea level changes. Unfortunately, locating a reference point which is truly stable over long time spans will be extremely difficult, if not impossible. How well a specific sea level variation pattern can be detected depends on the sea level variations them-selves, the quality of the tide gauge measurements and, if applicable, the quality ofgeodetic measurements used to connect the tide gauge bench marks in height. Based on existing literature, it has been tried to gain a clear understanding of these various aspects. Unfortunately, in the literature studied on processes which can influence relative sea-level heights, (almost) no mention is made of long-periodic processes (periods over 20 years), while analysis of tide gauge records shows that long-periodic fluctuations with significant amplitudes do occur in sea level height time series. Sea level heights as used in this thesis are annual mean sea levels. The quality of these annual mean values not only depends on the quality of the tide gauge measurements, but also on the frequency of these measurements. Not only the quality of state-of-the-art techniques is important, but also of tide gauges and measuring frequencies which were used in the past. Since estimating long-term sea level variation curves requires long sea level height series, historical measurements have to be used as well. In chapter 3, an overview is given of the measuring precision and systematic errors and limitations characteristic for the six tide gauge systems commonly used during the last century. Based on information available for Dutch tide gauges, an estimate is given of how much the quality of annual mean sea levels deteriorates if mean values arc based on, e.g., mean tide levels instead of on hourly measurements. If data for a number of tide gauges is available, a common sea level variation curve, e.g., applying to the Dutch coast, can be estimated. Since tide gauge measurements are relative to the local tide gauge bench mark, any vertical movements of the tide gauges relative to one another will have introduced inconsistencies between the individual time series. These inconsistencies reduce the quality of a common sea level variation curve based on these tide gauge series. As long as tide gauges experience only secular height movements relative to one another, the common oscillation pattern can still be discerned using techniques like svd. However, the slope of the estimated common variation curve is determined by the rate of vertical movements of the individual tide gauges. If tide gauges undergo vertical movements which vary in rate and over time, the common oscillation pattern will be affected as well. By relating all sea level height series to the same reference frame (e.g., nap) internal differences in relative sea level due to vertical movements of the tide gauge bench marks are removed from the data sets. Ideally, permanent monitoring of the tide gauge bench marks is applied.
Nowadays, this can be achieved by means of tips. However, in the past height differences were usually based on spirit levelling. In chapter 6, the quality of three geodetic techniques, i.e., gps, gravimetry, and spirit levelling is described. In addition, limitations of these techniques when applied to monitoring height changes of tide gauge bench marks arc discussed. Since changes in local gravity represent both variations in mass and changes in station height, gravimetry is not well suited for determining height differences. Uncertainties in height differences obtained by GPS can be reduced to within 1 cm. However, the quality of these measurements might be less in harbor areas (e.g., due to signal interference). GPS has the advantage that it allows for permanent monitoring over large distances, but measurements are only available for the last few decades. Spirit leveling can produce high precision height differences (over short distances), but is time consuming and prone to systematic errors (especially over long distances). However, leveled height differences arc often the only type of height information available. In the past, tide gauge bench marks have (hopefully) been connected to a local reference frame. Between some neighboring local height datums, height differences have occasionally been obtained as well. However, only since the second European leveling network (UELN-73), the height difference between the continent of Europe and Scandinavia and Great Britain respectively is available. These height connections consist of only a single connection line and, consequently, errors in these height differences cannot be detected by testing. In chapter 8, an indirect method is introduced for connecting vertical datums, which results in dynamic height differences between the fundamental stations in the various height datum zones. An advantage of this method is that quality information (both precision and reliability) of the estimated height differences can dc determined as well. Unfortunately, a high quality potential coefficient model is required. As a result, only if a new model (to be obtained from the planned GOCR mission) becomes available, height differences between datum zones could be derived with standard deviations of 1 cm.
The quality of sea level variation curves depends on the method used to estimate these curves. A number of data analysing techniques have been tested for their suitability for working with sea level height data. Sea level height time series have a number of specific characteristics, for instance non-stationarity, data quality which is not constant for the complete time series, and a wide range of periodic fluctuations with sometimes variable frequencies and amplitudes. As a result, most of the techniques examined do not work well when applied to sea level height data. It is found that the best techniques for smoothing sea level height series are moving average smoothing and Singular Spectrum Analysis, while estimates of future sea level heights should be based on cither AR(i)MA modelling or regression. To determine how well specific sea level variation patterns can be detected, experiments with a large variety of simulated sea level height time series have been performed. These simulated time series consist of the curve which needs to be detected (e.g., a linear trend), periodic fluctuations (based on actual tide gauge data) and simulated additional errors. This can cither be inaccuracies introduced by the tide gauge equipment or the height measurements, or (uncorrected for) height variations between tide gauge bench marks. By applying regression to the simulated time series, it is examined whether or not the original sea level variation curve can be recovered. It should be noted that statistical significance of estimated regression coefficients is no guarantee that the "true" sea level variation curve is detected. For example, if linear regression is applied to a sea level series following a quadratic curve, the estimated trend value can still be statistically significant. For this reason, often trend estimates are shown as a function of an increasing number of observations. For the above mentioned example, estimated trend values will steadily increase with an increasing number of included observations. Only if the model (of a linear regression line) fits the data, and if enough observations are available, estimated trend values will stabilise around the trend value actually present in the data set. First, experiments have been performed with sea level height data for a single tide gauge. In this case, the original data relative to the tide gauge bench mark can be used. If (based on external knowledge of the behavior of the local sea level) long-periodic fluctuations could be eliminated from the data set, the detectability of a single linear regression line depends on the trend value and the noise level of the measurements. For sea level data with a trend of 1.5 mm/yr, even if a noise level of 5 cm applies, this trend can be detected if 35 observations are available. If a simulated time series contains long-periodic fluctuations based on data for tide gauge Den Helder, of the order of 90 years of observations are required before trend estimates stabilise around the actual trend value on which the data set is based. Therefore, it is concluded that long-periodic fluctuations are the main factor in determining the amount of data required to detect a linear trend in a sea level height time series. In chapter 7, using six tide gauge data sets, a common sea level variation curve for the Dutch coast is estimated. In order to eliminate deviations from this common curve caused by height variations of the tide gauge bench marks relative to one another, all tide gauges have to be connected in height to the local reference system (nap). Inaccuracies in the required height connections introduce inconsistencies between the time series. Since the actual height connection history for the tide gauges is unknown, a number of scenarios have been used to simulate height connection errors. Experiments show that the quality of the estimated common variation curve not only depends on the precision of the height measurements, but also on the time span between subsequent height connections. For higher levels of connection noise, it is more pronounced that the larger the time span between subsequent connections, the less dependable the estimated trend values will be. In order to detect future sea level rise accelerations, historical data has to be used as well. Experiments show that, if long periods have elapsed between historic height connections, the precision of future height connections is of almost no importance. Increasing the standard deviation of future height measurements from 5 mm to 2 cm, or increasing the time span between height connections from one to 10 years, hardly influences the results. Finally, for the North Sea area, the quality of spatial variation patterns which can be derived based on trend values for 18 tide gauges, is examined. A spatial pattern in sea level height variations should be based on real differences in trend values for the various locations and not on variations resulting from measuring errors and height changes between tide gauge bench marks. Based on experiments with simulated time series, the following conclusions have been made. If height connections to a local reference frame are performed every 10 years, ranges of errors in trend estimates (as a function of latitude and longitude) are three times as large as results based on annual connection of heights. As a result of, e.g., post-glacial rebound, fundamental stations in the different datum zones can experience height changes relative to one another. If the individual time series (connected to the local datums) are not corrected for these relative vertical movements, this will result in large errors in the estimated spatial variation pattern. If height differences between vertical datum zones are based on results derived for European leveling networks, resulting errors in trend values (as a function of latitude and longitude) will be much larger than those caused by the post-glacial rebound movements (of the selected fundamental stations: Amsterdam, Newlyn, and Helsingborg) itself. This same holds for differences in vertical movements obtained by GPS measurements with a standard deviation of the order of 1 mm/yr.Note de contenu : 1 INTRODUCTION
Sea-level variations
Objectives of this thesis
Outline
2 TIDE GAUGE MEASUREMENTS
Introduction
Error characteristics of tide gauge instruments
Sampling rate and averaging method of tide gauge readings
Conclusions and recommendations
3 TECHNIQUES FOR ANALYSING SEA-LEVEL DATA
Introduction
Smoothing of tide gauge data
Prediction of future sea levels
Sea-level data for a group of tide gauges
Conclusions and recommendations
4 DETECTABILITY OF CURVES IN RELATIVE SEA LEVEL
Introduction
Estimating curves in individual time series
General structure of simulated data sets
" Ideal " measurement series
Time series containing short-periodic fluctuations
Time series containing short- and long periodic fluctuations
Conclusions and recommendations
5 CONNECTING TIDE GAUGES TO A LOCAL HEIGHT SYSTEM
Introduction
Problems related to the different " height " systems
Error characteristics of measuring techniques
Selection of observation sites
Required sampling and time span of measurements
6 DETECTABILITY OF CURVES IN SEA LEVEL RELATIVE TO A LOCAL DATUM
Introduction
General structure of simulated data sets
Same trend throughout the time series
Transition to higher trend at the beginning of the time series
Transition to higher trend at the end of the time series
Conclusions and recommendations
7 REGIONAL HEIGHT DATUM CONNECTION
Introduction
Adding datum shifts to a geodetic boundary value problem
Least squares solution of a vertical datum connection
A-priori covariance matrices
Datum connection in North-West Europe
" Ideal " cap size for terrestrial gravity measurements
Influence of the number of stations
Conclusions and recommendations
8 SEA-LEVEL VARIATION PATTERNS
Introduction
General structure of simulated data sets
Inconsistencies in annual mean values
Inconsistencies introduced by local height connections
Height datums experience linear movements
Vertical datum connection
Conclusions and recommendations
9 CONCLUSIONS AND RECOMMENDATIONS
Conclusions
General remarks concerning sea-level monitoring
Recommendations for future research
A Information concerning tide gauge stations
B Derivations
C Additionnal information concerning common variations curvesNuméro de notice : 11431 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54405 Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 11431-01 30.50 Livre Centre de documentation Géodésie Disponible Final results of the Baltic Sea level 1997 GPS campaign / Markku Poutanen (1999)
Titre : Final results of the Baltic Sea level 1997 GPS campaign : research works of the SSG 8.1 of the International Association of Geodesy Type de document : Rapport Auteurs : Markku Poutanen, Éditeur scientifique ; J. Kakkuri, Éditeur scientifique Editeur : Helsinki : Finnish Geodetic Institute FGI Année de publication : 1999 Collection : Reports of the Finnish Geodetic Institute num. 99-4 Importance : 182 p. Format : 21 x 30 cm Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] Baltique, mer
[Termes IGN] niveau moyen des mers
[Termes IGN] nivellement par GPS
[Termes IGN] réseau altimétrique local
[Termes IGN] traitement de données GNSSIndex. décimale : 30.50 Nivellement - généralités Numéro de notice : 53893 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Recueil / ouvrage collectif Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=43435 Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 53893-01 30.50 Livre Centre de documentation Géodésie Disponible Topex-Poséïdon, mesureur des océans / J.P. Penot in BT, Bibliothèque de Travail, n° 1103 (01/12/1998)PermalinkIGS-PSMSL workshop on methods for monitoring sea level / Ruth E. Neilan (1998)PermalinkOn the Unification of Indonesian Local Height Systems / Khafid (1998)PermalinkSea level changes / P.A. Pirazzoli (1998)PermalinkA European network for sea level and coastal land level monitoring / Trevor F. Baker in Journal of Marine Systems, vol 13 n° 1-4 (October 1997)PermalinkAufbereitung und Nutzung von Pegelmessungen für geodätische und geodynamische Zielstellungen / G. Liebsch (1997)PermalinkCompte-rendu de réunion du groupe de travail permanent du CNIG "Positionnement statique et dynamique", LRBA, Vernon, 5 juin 1997 / Pascal Willis (1997)PermalinkPrésentation du LAREG au Groupe Géodésie du CST et aux Journées de la Recherche, Marne-la-Vallée, 11 mars 1997 / Claude Boucher (1997)PermalinkLes séries chronologiques des marégraphes / Guy Wöppelmann (09/01/1996)PermalinkEtude du niveau des mers : séries chronologiques des marégraphes et géodésie spatiale / Guy Wöppelmann (1996)Permalink