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The ambiguous sea level rise at Brest’s 212 yearlong record elucidated / Huseyin Baki Iz in Journal of geodetic science, vol 11 n° 1 (January 2021)
[article]
Titre : The ambiguous sea level rise at Brest’s 212 yearlong record elucidated Type de document : Article/Communication Auteurs : Huseyin Baki Iz, Auteur ; C.K. Shum, Auteur Année de publication : 2021 Article en page(s) : pp 95 - 101 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] analyse diachronique
[Termes IGN] Brest
[Termes IGN] changement climatique
[Termes IGN] données marégraphiques
[Termes IGN] marégraphe
[Termes IGN] montée du niveau de la mer
[Termes IGN] série temporelleRésumé : (auteur) The tide gauge record at Brest, France, along Eastern part of Atlantic coast is one of the longest records in Europe spanning 212 years (1807–2019). Analyzing these records has important ramifications in assessing anthropogenic impact of climate change at local and regional scales during this period. All the previous studies that analyzed Brest’s tide gauge record have used vaguely defined quadratics models and did not incorporate the effect of sea level variations at various frequencies, which confounded the presence or absence of a plausible uniform acceleration. Here, we entertained two competing kinematic models; one with a uniform acceleration representing 212 years of monthly averaged tide gauge data, the other is a two-phase trend model (Phase I is 93 years long and Phase II is 119 years long). Both models include statistically significant (α= 0.05) common periodic effects, and sub and super harmonics of luni-solar origin for representing monthly averaged sea level anomalies observed at Brest. The least squares statistics for both models’ solutions cannot distinguish one model over the other, like earlier studies. However, the assessment of Phase I segment of the records disclosed the absence of a statistically significant trend and a uniform acceleration during this period. This outcome eliminates conclusively the occurrence of a uniform acceleration during the entire 212-year data span of the tide gauge record at Brest, favoring the two-phase trend model as a sound alternative. Numéro de notice : A2021-981 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/jogs-2020-0124 Date de publication en ligne : 20/09/2021 En ligne : https://doi.org/10.1515/jogs-2020-0124 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100978
in Journal of geodetic science > vol 11 n° 1 (January 2021) . - pp 95 - 101[article]Benefits of combining GPS and GLONASS for measuring ocean tide loading displacement / Majid Abbaszadeh in Journal of geodesy, vol 94 n° 7 (July 2020)
[article]
Titre : Benefits of combining GPS and GLONASS for measuring ocean tide loading displacement Type de document : Article/Communication Auteurs : Majid Abbaszadeh, Auteur ; Peter J. Clarke, Auteur Année de publication : 2020 Article en page(s) : n° 63 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] constellation GLONASS
[Termes IGN] données GLONASS
[Termes IGN] données GPS
[Termes IGN] données marégraphiques
[Termes IGN] marée océanique
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement ponctuel précis
[Termes IGN] surcharge océanique
[Termes IGN] trajet multipleRésumé : (auteur) GPS has been used to estimate ocean tide loading (OTL) height displacement amplitudes to accuracies of within 0.5 mm at the M2 frequency, but such estimation has been problematic at luni-solar K2 and K1 frequencies because they coincide with the GPS orbital period and revisit period, leading to repeating multipath and satellite orbit errors. We therefore investigate the potential of using the GLONASS constellation (with orbital period 11.26 h and true site revisit period of 8 sidereal days distinct from K2 and K1) for OTL displacement estimation, analysing 3–7 years of GPS and GLONASS data from 49 globally distributed stations. Using the PANDA software in kinematic precise point positioning mode with float ambiguities, we demonstrate that GLONASS can estimate OTL height displacement at the M2, N2, O1 and Q1 lunar frequencies with similar accuracy to GPS: 95th percentile agreements of 0.6–1.3 mm between estimated and FES2014b ocean tide model displacements. At the K2 and K1 luni-solar frequencies, 95th percentile agreements between GPS estimates and model values of 3.9–4.4 mm improved to 2.0–2.8 mm using GLONASS-only solutions. A combined GPS+GLONASS float solution improves accuracy of the lunar OTL constituents and P1 (but not significantly for K1 or K2) compared with a single-constellation solution and results in hourly-to-weekly spectral noise very similar to a GPS ambiguity-fixed solution, but without needing uncalibrated phase delay information. GLONASS estimates are more accurate at higher compared with lower latitudes because of improved satellite visibility, although this can be countered by using a lower elevation cut-off angle. Numéro de notice : A2020-535 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-020-01393-5 Date de publication en ligne : 08/07/2020 En ligne : https://doi.org/10.1007/s00190-020-01393-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95727
in Journal of geodesy > vol 94 n° 7 (July 2020) . - n° 63[article]Validation of Sentinel-3A SRAL coastal sea level data at high posting rate: 80 Hz / Ana Aldarias in IEEE Transactions on geoscience and remote sensing, vol 58 n° 6 (June 2020)
[article]
Titre : Validation of Sentinel-3A SRAL coastal sea level data at high posting rate: 80 Hz Type de document : Article/Communication Auteurs : Ana Aldarias, Auteur ; Jesus Gomez-Enri, Auteur ; Irene Laiz, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 3809 - 3821 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] coefficient de corrélation
[Termes IGN] correction troposphérique
[Termes IGN] courbe de Pearson
[Termes IGN] données altimétriques
[Termes IGN] données marégraphiques
[Termes IGN] eaux côtières
[Termes IGN] erreur moyenne quadratique
[Termes IGN] Espagne
[Termes IGN] forme d'onde
[Termes IGN] image Sentinel-SRAL
[Termes IGN] niveau de la mer
[Termes IGN] série temporelleRésumé : (auteur) Altimetry data of two and a half years (June 2016–November 2018) of Sentinel-3A SRAL (S3A-SRAL) were validated at the sampling frequency of 80 Hz. The data were obtained from the European Space Agency (ESA) Grid Processing On Demand (GPOD) service over three coastal sites in Spain: Huelva (HU) (Gulf of Cádiz), Barcelona (BA) (Western Mediterranean Sea), and Bilbao (BI) (Bay of Biscay). Two tracks were selected in each site: one ascending and one descending. Data were validated using in situ tide gauge (TG) data provided by the Spanish Puertos del Estado. The altimetry sea level anomaly time series were obtained using the corrections available in GPOD with the exception of the sea state bias (SSB) correction, not available at 80 Hz. Hence, the SSB was approximated to 5% of the significant wave height (SWH). The validation was performed using two statistical parameters, the Pearson correlation coefficient (r) and the root mean square error (rmse). In the 5–20-km segment with respect to the coastline, the results were 6–8 cm (rmse) and 0.7–0.8 (r) for all the tracks. The 0–5-km segment was also analyzed in detail to study the land effect on the altimetry data quality. The results showed that the track orientation, the angle of intersection with the coast, and the land topography concur to determine the nearest distance to the coast at which the data retain a similar level of accuracy than in the 5–20-km segment. This “distance of good quality” to shore reaches a minimum of 3 km for the tracks at HU and the descending track at BA. Numéro de notice : A2020-281 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2019.2957649 Date de publication en ligne : 01/01/2020 En ligne : https://doi.org/10.1109/TGRS.2019.2957649 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95102
in IEEE Transactions on geoscience and remote sensing > vol 58 n° 6 (June 2020) . - pp 3809 - 3821[article]Recent sea level change in the black sea from satellite altimetry and tide gauge observations / Nevin Betül Avsar in ISPRS International journal of geo-information, vol 9 n° 3 (March 2020)
[article]
Titre : Recent sea level change in the black sea from satellite altimetry and tide gauge observations Type de document : Article/Communication Auteurs : Nevin Betül Avsar, Auteur ; H.S. Kutoglu, Auteur Année de publication : 2020 Article en page(s) : 18 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] altimétrie
[Termes IGN] déformation verticale de la croute terrestre
[Termes IGN] données GNSS
[Termes IGN] données marégraphiques
[Termes IGN] données satellitaires
[Termes IGN] données topographiques
[Termes IGN] érosion côtière
[Termes IGN] marégraphe
[Termes IGN] montée du niveau de la mer
[Termes IGN] Noire, mer
[Termes IGN] série temporelle
[Termes IGN] surcharge hydrologique
[Termes IGN] variation saisonnière
[Vedettes matières IGN] AltimétrieRésumé : (auteur) Global mean sea level has been rising at an increasing rate, especially since the early 19th century in response to ocean thermal expansion and ice sheet melting. The possible consequences of sea level rise pose a significant threat to coastal cities, inhabitants, infrastructure, wetlands, ecosystems, and beaches. Sea level changes are not geographically uniform. This study focuses on present-day sea level changes in the Black Sea using satellite altimetry and tide gauge data. The multi-mission gridded satellite altimetry data from January 1993 to May 2017 indicated a mean rate of sea level rise of 2.5 ± 0.5 mm/year over the entire Black Sea. However, when considering the dominant cycles of the Black Sea level time series, an apparent (significant) variation was seen until 2014, and the rise in the mean sea level has been estimated at about 3.2 ± 0.6 mm/year. Coastal sea level, which was assessed using the available data from 12 tide gauge stations, has generally risen (except for the Bourgas Station). For instance, from the western coast to the southern coast of the Black Sea, in Constantza, Sevastopol, Tuapse, Batumi, Trabzon, Amasra, Sile, and Igneada, the relative rise was 3.02, 1.56, 2.92, 3.52, 2.33, 3.43, 5.03, and 6.94 mm/year, respectively, for varying periods over 1922–2014. The highest and lowest rises in the mean level of the Black Sea were in Poti (7.01 mm/year) and in Varna (1.53 mm/year), respectively. Measurements from six Global Navigation Satellite System (GNSS) stations, which are very close to the tide gauges, also suggest that there were significant vertical land movements at some tide gauge locations. This study confirmed that according to the obtained average annual phase value of sea level observations, seasonal sea level variations in the Black Sea reach their maximum annual amplitude in May–June. Numéro de notice : A2020-254 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/ijgi9030185 Date de publication en ligne : 20/03/2020 En ligne : https://doi.org/10.3390/ijgi9030185 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95008
in ISPRS International journal of geo-information > vol 9 n° 3 (March 2020) . - 18 p.[article]Validation of marine geoid models by utilizing hydrodynamic model and shipborne GNSS profiles / Sander Varbla in Marine geodesy, Vol 43 n° 2 (March 2020)
[article]
Titre : Validation of marine geoid models by utilizing hydrodynamic model and shipborne GNSS profiles Type de document : Article/Communication Auteurs : Sander Varbla, Auteur ; Artu Ellmann, Auteur ; Nicole Delpeche-Ellmann, Auteur Année de publication : 2020 Article en page(s) : pp 134 - 162 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] Baltique, mer
[Termes IGN] données marégraphiques
[Termes IGN] force de gravitation
[Termes IGN] geoïde marin
[Termes IGN] instrument embarqué
[Termes IGN] instrumentation GNSS
[Termes IGN] levé gravimétrique
[Termes IGN] navire
[Termes IGN] niveau de la mer
[Termes IGN] simulation hydrodynamiqueRésumé : (auteur) An essential role of the FAMOS international cooperation project is to obtain new marine gravity observations over the Baltic Sea for improving gravimetric geoid modelling. To achieve targeted 5 cm modelling accuracy, it is important to acquire new gravimetric data, as the existing data over some regions are inaccurate and sparse. As the accuracy of contemporary geoid models over marine areas remains unknown, it is important to evaluate geoid modelling outcome by independent data. Thus, this study presents results of a shipborne marine gravity and GNSS campaign for validation of existing geoid models conducted in the eastern section of the Baltic Sea. Challenging aspects for utilizing shipborne GNSS profiles tend to be with quantifying vessel’s attitude, processing of noise in the data and referencing to the required datum. Consequently, the novelty of this study is in the development of methodology that considers the above-mentioned challenges. In addition, tide gauge records in conjunction with an operational hydrodynamic model are used to identify offshore sea level dynamics during the marine measurements. The results show improvements in geoid modelling due to new marine gravimetric data. It is concluded that the marine GNSS profiles can potentially provide complementary constraints in problematic geoid modelling areas. Numéro de notice : A2020-051 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1080/01490419.2019.1701153 Date de publication en ligne : 20/01/2020 En ligne : https://doi.org/10.1080/01490419.2019.1701153 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94918
in Marine geodesy > Vol 43 n° 2 (March 2020) . - pp 134 - 162[article]Coastal sea level and related fields from existing observing systems / Marta Marcos in Surveys in Geophysics, vol 40 n° 6 (November 2019)PermalinkIntroducing a vertical land motion model for improving estimates of sea level rates derived from tide gauge records affected by earthquakes / Anna Klos in GPS solutions, vol 23 n° 4 (October 2019)PermalinkAnalysis of ocean tide loading displacements by GPS kinematic precise point positioning: a case study at the China coastal site SHAO / H. Zhao in Survey review, vol 51 n° 365 (March 2019)PermalinkA comparative study between least square and total least square methods for time-series analysis and quality control of sea level observations / Mahmoud Pirooznia in Marine geodesy, vol 42 n° 2 (March 2019)PermalinkApports de l'imagerie satellitaire pour caractériser les évolutions morphologiques de l'embouchure du Tage / Anne Jaouen (2019)PermalinkVariabilité du niveau marin relatif le long du littoral de Brest (France) par combinaison de méthodes géodésiques spatiales (altimétrie radar, InSAR et GPS) / Cyril Poitevin (2019)PermalinkThe effect of regional sea level atmospheric pressure on sea level variations at globally distributed tide gauge stations with long records / Huseyin Baki Iz in Journal of geodetic science, vol 8 n° 1 (January 2018)PermalinkReconstruction of time-varying tidal flat topography using optical remote sensing imageries / Kuo-Hsin Tseng in ISPRS Journal of photogrammetry and remote sensing, vol 131 (September 2017)PermalinkAcceleration of the global coastal sea level rise during the 20th century re-evaluated / Huseyin Baki Iz in Journal of geodetic science, vol 7 n° 1 (February 2017)PermalinkL’évolution du niveau de la mer / Alain Coulomb in Naturellement, n° 122 (Juin 2016)Permalink