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Towards a global seasonal and permanent reference water product from Sentinel-1/2 data for improved flood mapping / Sandro Martinis in Remote sensing of environment, vol 278 (September 2022)
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Titre : Towards a global seasonal and permanent reference water product from Sentinel-1/2 data for improved flood mapping Type de document : Article/Communication Auteurs : Sandro Martinis, Auteur ; Sandro Groth, Auteur ; Marc Wieland, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 113077 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image mixte
[Termes IGN] Allemagne
[Termes IGN] Australie
[Termes IGN] carte thématique
[Termes IGN] fusion d'images
[Termes IGN] image radar moirée
[Termes IGN] image Sentinel-MSI
[Termes IGN] image Sentinel-SAR
[Termes IGN] Inde
[Termes IGN] inondation
[Termes IGN] Mozambique
[Termes IGN] prévention des risques
[Termes IGN] série temporelle
[Termes IGN] Soudan
[Termes IGN] surveillance hydrologique
[Termes IGN] variation saisonnière
[Termes IGN] zone à risqueRésumé : (auteur) Satellite-based flood mapping has become an important part of disaster response. In order to accurately distinguish flood inundation from normally present conditions, up-to-date, high-resolution information on the seasonal water cover is crucial. This information is usually neglected in disaster management, which may result in a non-reliable representation of the flood extent, mainly in regions with highly dynamic hydrological conditions. In this study, we present a fully automated method to generate a global reference water product specifically designed for the use in global flood mapping applications based on high resolution Earth Observation data. The proposed methodology combines existing processing pipelines for flood detection based on Sentinel-1/2 data and aggregates permanent as well as seasonal water masks over an adjustable reference time period. The water masks are primarily based on the analysis of Sentinel-2 data and are complemented by Sentinel-1-based information in optical data scarce regions. First results are demonstrated in five selected study areas (Australia, Germany, India, Mozambique, and Sudan), distributed across different climate zones and are systematically compared with external products. Further, the proposed product is exemplary applied to three real flood events in order to evaluate the impact of the used reference water mask on the derived flood extent. Results show, that it is possible to generate a consistent reference water product at 10–20 m spatial resolution, that is more suitable for the use in rapid disaster response than previous masks. The proposed multi-sensor approach is capable of producing reasonable results, even if only few or no information from optical data is available. Further it becomes clear, that the consideration of seasonality of water bodies, especially in regions with highly dynamic hydrological and climatic conditions, reduces potential over-estimation of the inundation extent and gives a more reliable picture on flood-affected areas. Numéro de notice : A2022-467 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1016/j.rse.2022.113077 Date de publication en ligne : 17/05/2022 En ligne : https://doi.org/10.1016/j.rse.2022.113077 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100801
in Remote sensing of environment > vol 278 (September 2022) . - n° 113077[article]The role of blue green infrastructure in the urban thermal environment across seasons and local climate zones in East Africa / Xueqin Li in Sustainable Cities and Society, vol 80 (May 2022)
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Titre : The role of blue green infrastructure in the urban thermal environment across seasons and local climate zones in East Africa Type de document : Article/Communication Auteurs : Xueqin Li, Auteur ; Lindsay C. Stringer, Auteur ; Martin Dallimer, Auteur Année de publication : 2022 Article en page(s) : n° 103798 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] changement climatique
[Termes IGN] climat local
[Termes IGN] corrélation automatique de points homologues
[Termes IGN] croissance urbaine
[Termes IGN] espace vert
[Termes IGN] Ethiopie
[Termes IGN] Google Earth Engine
[Termes IGN] ilot thermique urbain
[Termes IGN] indice de végétation
[Termes IGN] Ouganda
[Termes IGN] saison
[Termes IGN] série temporelle
[Termes IGN] Soudan
[Termes IGN] Tanzanie
[Termes IGN] température au sol
[Termes IGN] zone urbaine denseRésumé : (auteur) Rapid urbanisation and climate change are two major trends in Africa in need of further investigation. In this paper, the urban thermal environment and vegetation abundance in four East African cities (Khartoum, Addis Ababa, Kampala and Dar es Salaam) were characterised, providing new insights into the role and potentials of blue green infrastructure in differing climate regions. The Local Climate Zone (LCZ) framework was employed to detect the seasonal Land Surface Temperature (LST) and Enhanced Vegetation Index (EVI) derived from Landsat-8 data. Significant LST differences between LCZs in dry and rainy seasons were confirmed using a Welch's T test. The LCZs were found to offer potentially new approaches to investigating issues pertaining to urban heating in data-scarce regions. Greater surface urban heat island (SUHI) intensity during the rainy season was apparent in Khartoum and Addis Ababa, emphasising the importance of seasonality in urban thermal studies. Spatial correlations between EVI and LST within each LCZ were analysed through Moran's I and further illustrated the complex relationships of vegetation and thermal behaviour in urban areas. Despite these complexities, urban blue green infrastructure was found to moderate the SUHI, with different types of intervention required across different LCZs. Numéro de notice : A2022-269 Affiliation des auteurs : non IGN Thématique : IMAGERIE/URBANISME Nature : Article DOI : 10.1016/j.scs.2022.103798 Date de publication en ligne : 23/02/2022 En ligne : https://doi.org/10.1016/j.scs.2022.103798 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100280
in Sustainable Cities and Society > vol 80 (May 2022) . - n° 103798[article]Mask R-CNN-based building extraction from VHR satellite data in operational humanitarian action: An example related to Covid-19 response in Khartoum, Sudan / Dirk Tiede in Transactions in GIS, Vol 25 n° 3 (June 2021)
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Titre : Mask R-CNN-based building extraction from VHR satellite data in operational humanitarian action: An example related to Covid-19 response in Khartoum, Sudan Type de document : Article/Communication Auteurs : Dirk Tiede, Auteur ; Gina Schwendemann, Auteur ; Ahmad Alobaidi, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 1213-1227 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse d'image orientée objet
[Termes IGN] apprentissage profond
[Termes IGN] classification par réseau neuronal convolutif
[Termes IGN] détection du bâti
[Termes IGN] échantillonnage
[Termes IGN] épidémie
[Termes IGN] gestion de crise
[Termes IGN] HRV (capteur)
[Termes IGN] image à très haute résolution
[Termes IGN] image Pléiades-HR
[Termes IGN] itération
[Termes IGN] SoudanRésumé : Auteur) Within the constraints of operational work supporting humanitarian organizations in their response to the Covid-19 pandemic, we conducted building extraction for Khartoum, Sudan. We extracted approximately 1.2 million dwellings and buildings, using a Mask R-CNN deep learning approach from a Pléiades very high-resolution satellite image with 0.5 m pixel resolution. Starting from an untrained network, we digitized a few hundred samples and iteratively increased the number of samples by validating initial classification results and adding them to the sample collection. We were able to strike a balance between the need for timely information and the accuracy of the result by combining the output from three different models, each aiming at distinctive types of buildings, in a post-processing workflow. We obtained a recall of 0.78, precision of 0.77 and F1 score of 0.78, and were able to deliver first results in only 10 days after the initial request. The procedure shows the great potential of convolutional neural network frameworks in combination with GIS routines for dwelling extraction even in an operational setting. Numéro de notice : A2021-464 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12766 Date de publication en ligne : 06/05/2021 En ligne : https://doi.org/10.1111/tgis.12766 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98060
in Transactions in GIS > Vol 25 n° 3 (June 2021) . - pp 1213-1227[article]Geomorphology and (palaeo-)hydrography of the Southern Atbai plain and western Eritrean Highlands (Eastern Sudan/Western Eritrea) / Stefano Costanzo in Journal of maps, vol 17 n° 2 (February 2021)
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Titre : Geomorphology and (palaeo-)hydrography of the Southern Atbai plain and western Eritrean Highlands (Eastern Sudan/Western Eritrea) Type de document : Article/Communication Auteurs : Stefano Costanzo, Auteur ; Andrea Zerboni, Auteur ; Mauro Cremaschi, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 51 - 62 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie thématique
[Termes IGN] analyse du paysage
[Termes IGN] carte géomorphologique
[Termes IGN] ère quaternaire
[Termes IGN] Erythrée
[Termes IGN] hydrographie
[Termes IGN] montagne
[Termes IGN] roche
[Termes IGN] Sahel
[Termes IGN] Soudan
[Termes IGN] tectoniqueRésumé : (auteur) We present the geomorphology of the Southern Atbai Plain (Eastern Sudan) and the western edge of the Eritrean Highlands (Western Eritrea), in the eastern Sahel. The mountainous area consists of Paleo-Proterozoic gneiss and Neo-Proterozoic igneous rocks and meta-volcanic assemblages shaped as inselbergs and whaleback landforms by weathering. Bare-rock hills emerge from a gentle glacis that oversees the Southern Atbai alluvial plain, located between the Atbara and Gash Rivers. The plain features the SSE-NNW-oriented endorheic terminal fan of the Gash River and is crossed by intricate Early to Late Pleistocene paleochannels, whose evolution was controlled by the interplay between Quaternary regional tectonics and arid to humid climatic and environmental oscillations. The map is intended to interpret the evolution of local landscape, thus representing a tool for reconstructing the spatial and temporal distribution of Late Quaternary archaeological features and their functional relationships with the fossil fluvial system and the western foothills. Numéro de notice : A2021-201 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/17445647.2020.1869112 Date de publication en ligne : 17/01/2021 En ligne : https://doi.org/10.1080/17445647.2020.1869112 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97156
in Journal of maps > vol 17 n° 2 (February 2021) . - pp 51 - 62[article]Displacement monitoring of upper Atbara dam based on time series InSAR / Q.Q. Wang in Survey review, vol 52 n° 375 (November 2020)
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Titre : Displacement monitoring of upper Atbara dam based on time series InSAR Type de document : Article/Communication Auteurs : Q.Q. Wang, Auteur ; Q.H. Huang, Auteur ; N. He, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 485 - 496 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] auscultation d'ouvrage
[Termes IGN] barrage
[Termes IGN] déformation d'édifice
[Termes IGN] érosion hydrique
[Termes IGN] image radar moirée
[Termes IGN] image Sentinel-SAR
[Termes IGN] série temporelle
[Termes IGN] Soudan
[Termes IGN] surveillance d'ouvrageRésumé : (auteur) Dam is an important part of engineering structure, in the process of dam construction, the dam monitoring is crucial since water erosion and time-dependent motion may cause deformation. Traditional monitoring methods are time-consuming and labour-intensive. However, Interferometric Synthetic Aperture Radar (InSAR) can provide precise and spatially dense information on slow deformations. This research investigated the longest earth-rock-fill dam in Sudan to determine the spatial and temporal deformations Sentinel-1A descending SAR images were further used to analyse the issues mentioned above. The results suggested that the dam existed the maximum displacement with a value up to 190 mm on the dam crest. Besides, the selected sections along the riverbed of the dam were analysed and the RMSE was approximately 2 mm/year. The results were in good agreement with the in situ measurements, indicating the advancement of time series InSAR in dam deformation monitoring. Numéro de notice : A2020-686 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2019.1643529 Date de publication en ligne : 17/07/2019 En ligne : https://doi.org/10.1080/00396265.2019.1643529 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96217
in Survey review > vol 52 n° 375 (November 2020) . - pp 485 - 496[article]Earth observation-based multi-scale impact assessment of internally displaced person (IDP) camps on wood resources in Zalingei, Darfur / Kristin Spröhnle in Geocarto international, vol 31 n° 5 - 6 (May - June 2016)
PermalinkPermalinkQuality assessment of Defense geographic data, e.g. the Darfur E.U. protection mission / Jean-Paul Sempère (2009)
PermalinkDe l'eau au Darfour grâce aux satellites d'observation de la terre / Françoise de Blomac in SIG la lettre, n° 60 (octobre 2004)
PermalinkRemote sensing applications for sustainable watershed management and food security / G. Rochon (2001)
PermalinkRadar and optical data integration for land-use-land-cover mapping / B.N. Haack in Photogrammetric Engineering & Remote Sensing, PERS, vol 66 n° 6 (June 2000)
PermalinkProcedures for woody vegetation surveys in the Kazgail rural council area, Kordofan, Sudan / A. Falconer in Geocarto international, vol 5 n° 3 (September - November 1990)
PermalinkDetection of circular geological features using the Hough transform / A.M. Cross in International Journal of Remote Sensing IJRS, vol 9 n° 9 (September 1988)
PermalinkA comparative analysis of dyke lineaments mapped from Shuttle-Imaging-Radar and large format camera photography in hyperarid areas of the eastern desert, Egypt, and red sea hills, Sudan / B.N. Koopmans in International Journal of Remote Sensing IJRS, vol 9 n° 5 (May 1988)
PermalinkMeasurement of canopy interception of solar radiation by stands of trees in sparsely wooded savanna / S.D. Prince in International Journal of Remote Sensing IJRS, vol 8 n° 12 (December 1987)
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