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Coastline change modelling induced by climate change using geospatial techniques in Togo (West Africa) / Yawo Konko in Advances in Remote Sensing, vol 9 n° 2 (June 2020)
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Titre : Coastline change modelling induced by climate change using geospatial techniques in Togo (West Africa) Type de document : Article/Communication Auteurs : Yawo Konko, Auteur ; Appollonia Okhimambe, Auteur ; Pouwèréou Nimon, Auteur ; Jerry Asaana, Auteur ; Jean-Paul Rudant , Auteur ; Kouami Kokou, Auteur
Année de publication : 2020 Projets : 1-Pas de projet / Article en page(s) : pp 85 - 100 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes descripteurs IGN] changement climatique
[Termes descripteurs IGN] classification non dirigée
[Termes descripteurs IGN] classification par séparateurs à vaste marge
[Termes descripteurs IGN] données multisources
[Termes descripteurs IGN] érosion côtière
[Termes descripteurs IGN] image Landsat-ETM+
[Termes descripteurs IGN] image Sentinel-MSI
[Termes descripteurs IGN] niveau de la mer
[Termes descripteurs IGN] Normalized Difference Water Index
[Termes descripteurs IGN] outil d'aide à la décision
[Termes descripteurs IGN] régression linéaire
[Termes descripteurs IGN] série temporelle
[Termes descripteurs IGN] surveillance du littoral
[Termes descripteurs IGN] Togo
[Termes descripteurs IGN] trait de côteRésumé : (auteur) Climate change is a major concern of humanity. One of the consequences of climate change is global warming causing melting glaciers, rising sea levels and shoreline regression. In Togo, the regression of shoreline leads to coastal erosion with significant damage on socio-economic infrastructures and human habitats. This research, basing on geospatial techniques, focuses on coastal erosion monitoring from 1988 to 2018 in Togo. It is interested in the extraction of shoreline and in the analysis of change. Various satellite images indexes have been developed for shoreline extraction but the major scientific problem concerns the precision of the different classification algorithms methods used for the extraction of the shoreline from these water index. This study used NDWI index from multisource satellite images. It assesses the performance of Otsu threshold segmentation, Iso Cluster Unsupervised Classification and Support Vector Machine (SVM) Supervised Classification methods for the extraction of the shoreline on NDWI index. The topographic morphology such as linear and non-linear coastal surfaces have been considered. The estimation of the rates of change of the shoreline was performed using the statistical linear regression method (LRR). The results revealed that the SVM Supervised Classification method showed good performance on linear and non-linear coastal surface than the other methods. For the kinematics of the shoreline, the southwest of the Togolese coast has an average erosion rate ranging from 2.49 to 5.07 m per year. The results obtained will serve as decision-making support tools for the design and implementation of appropriate adaptations plans to avoid the immersion of the asphalt road by sea, displacement of population and disturbance of human habitats. Numéro de notice : A2020-795 Affiliation des auteurs : UGE-LaSTIG+Ext (2020- ) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.4236/ars.2020.92005 date de publication en ligne : 08/06/2020 En ligne : https://doi.org/10.4236/ars.2020.92005 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96622
in Advances in Remote Sensing > vol 9 n° 2 (June 2020) . - pp 85 - 100[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)
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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 descripteurs IGN] coefficient de corrélation
[Termes descripteurs IGN] correction troposphérique
[Termes descripteurs IGN] courbe de Pearson
[Termes descripteurs IGN] données altimétriques
[Termes descripteurs IGN] données marégraphiques
[Termes descripteurs IGN] eaux côtières
[Termes descripteurs IGN] erreur moyenne quadratique
[Termes descripteurs IGN] Espagne
[Termes descripteurs IGN] forme d'onde
[Termes descripteurs IGN] image Sentinel-SRAL
[Termes descripteurs IGN] niveau de la mer
[Termes descripteurs 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]Optimal lowest astronomical tide estimation using maximum likelihood estimator with multiple ocean models hybridization / Mohammed El-Diasty in ISPRS International journal of geo-information, vol 9 n° 5 (May 2020)
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Titre : Optimal lowest astronomical tide estimation using maximum likelihood estimator with multiple ocean models hybridization Type de document : Article/Communication Auteurs : Mohammed El-Diasty, Auteur Année de publication : 2020 Article en page(s) : 11 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Océanographie
[Termes descripteurs IGN] carte marine
[Termes descripteurs IGN] données hydrographiques
[Termes descripteurs IGN] incertitude des données
[Termes descripteurs IGN] levé hydrographique
[Termes descripteurs IGN] marée océanique
[Termes descripteurs IGN] marégraphe
[Termes descripteurs IGN] méthode du maximum de vraisemblance (estimation)
[Termes descripteurs IGN] modèle océanographique
[Termes descripteurs IGN] navigation maritime
[Termes descripteurs IGN] niveau de la mer
[Termes descripteurs IGN] océanographie dynamique
[Termes descripteurs IGN] Rouge, merRésumé : (auteur) Developing an accurate Lowest Astronomical Tide (LAT) in a continuous form is essential for many maritime applications as it can be employed to develop an accurate continuous vertical control datum for hydrographic surveys applications and to produce accurate dynamic electronic navigation charts for safe maritime navigation by mariners. The LAT can be developed in a continuous (surface) using an estimated LAT surface model from the hydrodynamic ocean model along with coastal discrete LAT point values derived from tide gauges data sets to provide the corrected LAT surface model. In this paper, an accurate LAT surface model was developed for the Red Sea case study using a Maximum Likelihood Estimator (MLE) with multiple hydrodynamic ocean models hybridization, namely, WebTide, FES2014, DTU10, and EOT11a models. It was found that the developed optimal hybrid LAT model using MLE with multiple hydrodynamic ocean models hybridization ranges from 0.1 m to 1.63 m, associated with about 2.4 cm of uncertainty at a 95% confidence level in the Red Sea case study area. To validate the accuracy of the developed model, the comparison was made between the optimal hybrid LAT model developed from multiple hydrodynamic ocean models hybridization using the MLE method with the individual LAT models estimated from individual WebTide, FES2014, DTU10, or EOT11a ocean models based on the associated uncertainties estimated at a 95% confidence level. It was found that the optimal hybrid LAT model accuracy is superior to the individual LAT models estimated from individual ocean models with an improvement of about 50% in average, based on the estimated uncertainties. The importance of developing optimal LAT surface model using the MLE method with multiple hydrodynamic ocean models hybridization in this paper with few centimeters level of uncertainty can lead to accurate continuous vertical datum estimation that is essential for many maritime applications. Numéro de notice : A2020-301 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/ijgi9050327 date de publication en ligne : 17/05/2020 En ligne : https://doi.org/10.3390/ijgi9050327 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95141
in ISPRS International journal of geo-information > vol 9 n° 5 (May 2020) . - 11 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)
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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 descripteurs IGN] Baltique, mer
[Termes descripteurs IGN] données marégraphiques
[Termes descripteurs IGN] force de gravitation
[Termes descripteurs IGN] geoïde marin
[Termes descripteurs IGN] instrument embarqué
[Termes descripteurs IGN] instrumentation GNSS
[Termes descripteurs IGN] levé gravimétrique
[Termes descripteurs IGN] navire
[Termes descripteurs IGN] niveau de la mer
[Termes descripteurs 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)
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Titre : Coastal sea level and related fields from existing observing systems Type de document : Article/Communication Auteurs : Marta Marcos, Auteur ; Guy Wöppelmann, Auteur ; Andrew Matthews, Auteur ; Rui M. Ponte, Auteur ; Florence Birol, Auteur ; Fabrice Ardhuin, Auteur ; Giovanni Coco, Auteur ; Alvaro Santamaria Gomez, Auteur ; Valérie Ballu, Auteur ; Laurent Testut, Auteur ; Don Chambers, Auteur ; Justin E. Stopa, Auteur Année de publication : 2019 Article en page(s) : pp 1293 - 1317 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes descripteurs IGN] Amérique du nord
[Termes descripteurs IGN] données marégraphiques
[Termes descripteurs IGN] Europe (géographie politique)
[Termes descripteurs IGN] littoral
[Termes descripteurs IGN] niveau de la merRésumé : (auteur) We review the status of current sea-level observing systems with a focus on the coastal zone. Tide gauges are the major source of coastal sea-level observations monitoring most of the world coastlines, although with limited extent in Africa and part of South America. The longest tide gauge records, however, are unevenly distributed and mostly concentrated along the European and North American coasts. Tide gauges measure relative sea level but the monitoring of vertical land motion through high-precision GNSS, despite being essential to disentangle land and ocean contributions in tide gauge records, is only available in a limited number of stations. (25% of tide gauges have a GNSS station at less than 10 km.) Other data sources are new in situ observing systems fostered by recent progress in GNSS data processing (e.g., GPS reflectometry, GNSS-towed platforms) and coastal altimetry currently measuring sea level as close as 5 km from the coastline. Understanding observed coastal sea level also requires information on various contributing processes, and we provide an overview of some other relevant observing systems, including those on (offshore and coastal) wind waves and water density and mass changes. Numéro de notice : A2019-278 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10712-019-09513-3 date de publication en ligne : 05/02/2019 En ligne : https://doi.org/10.1007/s10712-019-09513-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95411
in Surveys in Geophysics > vol 40 n° 6 (November 2019) . - pp 1293 - 1317[article]Introducing 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)
PermalinkReal-time sea-level monitoring using Kalman filtering of GNSS-R data / Joakim Strandberg in GPS solutions, vol 23 n° 3 (July 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)
PermalinkSea level estimation from SNR data of geodetic receivers using wavelet analysis / Xiaolei Wang in GPS solutions, vol 23 n° 1 (January 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)
PermalinkPermalinkThe 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)
PermalinkPermalinkPermalinkExtension of satellite altimetry Jason-2 sea level anomalies towards the Red Sea coast using polynomial harmonic techniques / A. M. Taqi in Marine geodesy, vol 40 n° 5 (September 2017)
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