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Improved algorithms for the measurement of total precipitable water and cloud liquid water from SARAL microwave radiometer observations / Rajput Neha Mangalsinh in Marine geodesy, vol 42 n° 4 (July 2019)  

Public [article]  inMarine geodesy > vol 42 n° 4 (July 2019) . - pp 367 - 381 Titre : Improved algorithms for the measurement of total precipitable water and cloud liquid water from SARAL microwave radiometer observations Type de document : Article/Communication Auteurs : Rajput Neha Mangalsinh, Auteur ; Atul Kumar Varma, Auteur Année de publication : 2019 Article en page(s) : pp 367 - 381 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection [Termes descripteurs IGN] cryosphère [Termes descripteurs IGN] données altimétriques [Termes descripteurs IGN] hauteurs de mer [Termes descripteurs IGN] image GPM [Termes descripteurs IGN] image SSMIS [Termes descripteurs IGN] image TRMM-MI [Termes descripteurs IGN] nuage [Termes descripteurs IGN] précipitation [Termes descripteurs IGN] radiomètre à hyperfréquence [Termes descripteurs IGN] température de luminance [Termes descripteurs IGN] vapeur d'eau Résumé : (auteur) SARAL carried onboard a radar altimeter that provides very precise measurements of the sea surface height (SSH). Like other altimetric missions, SARAL carries a passive microwave radiometer (PMR) for wet tropospheric correction to SSH. In the present study, new algorithms are developed for the retrieval of cloud liquid water (CLW) and total precipitable water vapor (TPW) over the global oceans from PMR measurements of the brightness temperatures. A radiative transfer and genetic algorithm based retrieval scheme is proposed for the estimation of CLW and TPW from SARAL PMR. The comparisons of CLW from PMR with independent measurements from GPM-GMI and SSMIS within and outside ±40° latitudes show correlation (R) of 0.86 and 0.83, bias of 0.7 and −3.61 mg/cm2, and root mean square error (RMSE) of 8.42 and 8.07 mg/cm2, respectively. Similarly, TPW from PMR with GPM-GMI and SSMIS show R of 0.99 and 0.98, bias of −0.04 and −0.03 g/cm2 and RMSE of 0.17 and 0.17 g/cm2, respectively. The retrieval accuracy of CLW and TPW from the new algorithms is compared with these parameters provided in the SARAL geophysical data records as finished products, which showed substantial improvement in the quality of the parameters from the new algorithm. Numéro de notice : A2019-282 Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01490419.2019.1624662 date de publication en ligne : 12/06/2019 En ligne : https://doi.org/10.1080/01490419.2019.1624662 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93116 [article]

Landslide monitoring analysis of single-frequency BDS/GPS combined positioning with constraints on deformation characteristics / Dongwei Qiu in Survey review, vol 51 n° 367 (July 2019)  

Public [article]  inSurvey review > vol 51 n° 367 (July 2019) . - pp 364 - 372 Titre : Landslide monitoring analysis of single-frequency BDS/GPS combined positioning with constraints on deformation characteristics Type de document : Article/Communication Auteurs : Dongwei Qiu, Auteur ; Laiyang Wang, Auteur ; Dean Luo, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 364 - 372 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale [Termes descripteurs IGN] déformation de la croute terrestre [Termes descripteurs IGN] données lidar [Termes descripteurs IGN] données localisées 3D [Termes descripteurs IGN] effondrement de terrain [Termes descripteurs IGN] modèle de simulation [Termes descripteurs IGN] positionnement par BeiDou [Termes descripteurs IGN] positionnement par GPS [Termes descripteurs IGN] précipitation [Termes descripteurs IGN] récepteur monofréquence [Termes descripteurs IGN] simulation numérique [Termes descripteurs IGN] surveillance géologique Résumé : (Auteur) In order to optimise the selection of landslide monitoring points and save the cost of monitoring, a geological constitutive model was constructed by using 3D laser scanning and geological borehole data to simulate the relationship between rainfall and deformation. Thus, the main occurrence area and maximum deformation of the landslide were determined. Aiming at the deficiency of the single-epoch redundancy of the single-frequency GNSS receiver and the poor accuracy, this paper proposes a single-frequency BDS/GPS combined positioning and monitoring scheme with constraint of deformation features to restrict the search range of single-frequency ambiguity, obviously increase the ambiguity fixed success rate and then improve the BDS/GPS positioning accuracy. By contrast experiments, the landslide area obtained by numerical simulation basically matches with the on-site landslide area. The BDS/GPS combined positioning with constraint is consistent with the deep displacement changes, which can well reflect the displacement of the landslide body and make an early warning of disasters. Numéro de notice : A2019-364 Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2018.1467075 date de publication en ligne : 05/05/2018 En ligne : https://doi.org/10.1080/00396265.2018.1467075 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93449 [article]

A novel algorithm for differentiating cloud from snow sheets using Landsat 8 OLI imagery / Tingting Wu in Advances in space research, vol 64 n°1 (1 July 2019)  

Public [article]  inAdvances in space research > vol 64 n°1 (1 July 2019) . - pp 79 - 87 Titre : A novel algorithm for differentiating cloud from snow sheets using Landsat 8 OLI imagery Type de document : Article/Communication Auteurs : Tingting Wu, Auteur ; Ling Han, Auteur ; Qing Liu, Auteur Année de publication : 2019 Article en page(s) : pp 79 - 87 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique [Termes descripteurs IGN] analyse fractale [Termes descripteurs IGN] Chine [Termes descripteurs IGN] classification dirigée [Termes descripteurs IGN] détection des nuages [Termes descripteurs IGN] image Landsat-8 [Termes descripteurs IGN] image Landsat-OLI [Termes descripteurs IGN] neige [Termes descripteurs IGN] réflectance [Termes descripteurs IGN] seuillage d'image [Termes descripteurs IGN] signature spectrale Résumé : (auteur) The separation of clouds from snow is fundamentally very challenging because of their similar spectral signature. A new algorithm was proposed to detect clouds from snow in Landsat 8 imagery. Taking the Hetian District region, where there is frequent cloud and snow cover, in northwestern China as one of the typical case areas. The typical case is presented in detail to illustrate the approach produces and results. A band math method for cloud and snow discrimination index (CSDI) was firstly conducted in this paper, fractal digital number-frequency (DN-N) algorithm and hotspot analyses were applied to determine the threshold of the CSDI and eliminate false anomalies. The results showed that an overall accuracy exceeding 95% in areas with very bright land surfaces, which indicate that this algorithm is effective for detecting clouds in specific situations where the ground objects have some reflectance characteristics similar to cloud. Numéro de notice : A2019-398 Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2019.03.014 date de publication en ligne : 18/03/2019 En ligne : https://doi.org/10.1016/j.asr.2019.03.014 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93512 [article]

Analyzing the recent dynamics of wildland fires in Quercus suber L. woodlands in Sardinia (Italy), Corsica (France) and Catalonia (Spain) / Michele Salis in European Journal of Forest Research, vol 138 n° 3 (June 2019)  

Public [article]  inEuropean Journal of Forest Research > vol 138 n° 3 (June 2019) . - pp 415 - 431 Titre : Analyzing the recent dynamics of wildland fires in Quercus suber L. woodlands in Sardinia (Italy), Corsica (France) and Catalonia (Spain) Type de document : Article/Communication Auteurs : Michele Salis, Auteur ; Bachisio Arca, Auteur ; Fermin Alcasena-Urdiroz, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 415 - 431 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale [Termes descripteurs IGN] analyse spatio-temporelle [Termes descripteurs IGN] bassin méditerranéen [Termes descripteurs IGN] Catalogne (Espagne) [Termes descripteurs IGN] Corse [Termes descripteurs IGN] données socio-économiques [Termes descripteurs IGN] incendie de forêt [Termes descripteurs IGN] précipitation [Termes descripteurs IGN] quercus suber [Termes descripteurs IGN] régression logistique [Termes descripteurs IGN] Sardaigne Résumé : (Auteur) Wildland fires represent a major threat to Quercus suber L. ecosystems, which provide relevant socioeconomic and ecological services in the Mediterranean Basin. In this work, we analyzed recent wildland fire dynamics in cork oak woodlands along the fire-prone areas of Sardinia (Italy), Corsica (France) and Catalonia (Spain). We first characterized geographic extent and main characteristics of cork oak woodlands in these regions and analyzed how environmental (climate and elevation) and socioeconomic factors (population and land uses) vary in the areas covered by Quercus suber L. We then evaluated how wildfires affected cork oak stands and, by logistic regression analysis, to what extent wildfires in cork oak areas were related to the above set of environmental and anthropic explanatory variables. Results revealed specific variations across study areas in cork oak characteristics as well as in environmental and social factors. We highlighted the spatial and temporal patterns of wildfires on cork oak woodlands, in terms of extent, seasonality, frequency and main driving factors. In the period 2003–2015, the percentage of cork oak woodlands burned ranged from 3.42% in Corsica to 11.30% in Sardinia. A few large and severe wildfires accounted for most of the area burned in cork oak woodlands. The most significant predictive variable that explained the spatial variation in wildland fire ignitions inside or nearby cork oaks was summer precipitation, while the weight of other factors varied depending on the region. This study provides evidence on recent fire dynamics in cork oak woodlands and gives valuable information and insights for the implementation of forest management and planning strategies in the Mediterranean area. Numéro de notice : A2019-232 Thématique : FORET/GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10342-019-01179-1 date de publication en ligne : 20/02/2019 En ligne : https://doi.org/10.1007/s10342-019-01179-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92746 [article]

Site and age-dependent responses of Picea abies growth to climate variability / Petr Čermák in European Journal of Forest Research, vol 138 n° 3 (June 2019)  

Public [article]  inEuropean Journal of Forest Research > vol 138 n° 3 (June 2019) . - pp 445 - 460 Titre : Site and age-dependent responses of Picea abies growth to climate variability Type de document : Article/Communication Auteurs : Petr Čermák, Auteur ; Michal Rybníček, Auteur ; Tomas Zid, Auteur ; Non-répertorié, Auteur ; Non-répertorié, Auteur Année de publication : 2019 Article en page(s) : pp 445 - 460 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation [Termes descripteurs IGN] croissance végétale [Termes descripteurs IGN] dendrochronologie [Termes descripteurs IGN] forêt boréale [Termes descripteurs IGN] Norvège [Termes descripteurs IGN] Picea abies [Termes descripteurs IGN] précipitation [Termes descripteurs IGN] température au sol Résumé : (Auteur) Knowledge about spatiotemporal variability of climate change effect on tree-ring width (TRW) and crown condition is essential to optimize the modelling of future forest ecosystem responses to the changing climate. Geographical differences in the climate–growth relationship are a reflection of the regional climatic conditions mainly. In this study, 175 Picea abies trees from the north-western edge of its geographical distribution in Central Norway were evaluated with respect to geographical and age-dependent differences during the common period of 1950–2015. The results showed that the most significant positive correlations between TRW and the current June temperature were unstable although the temperature increased. The correlations suddenly started to decrease (regardless of the site placement and tree age) at the beginning of the 1990s, but subsequently unexpectedly increased in the 2010s. The superposed epoch analysis revealed longer TRW regeneration of the southern plots (except over-mature trees) after negative pointer years compared to the northern plots. Previous summer temperature and related physiological processes (cone crops, storage of nutrients, etc.) significantly negatively affected P. abies growth in the current year. Additionally, our results showed that the selection of the chronology version (standard or residual) significantly affects the resulting correlations and thus must be carefully considered in dendroclimatological studies. Our main outputs can contribute to better understanding of the climate–growth relationship variability and general prediction of the radial growth. Numéro de notice : A2019-233 Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10342-019-01182-6 date de publication en ligne : 23/02/2019 En ligne : https://doi.org/10.1007/s10342-019-01182-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92747 [article]

Evidence of climate effects on the height-diameter relationships of tree species / Mathieu Fortin in Annals of Forest Science [en ligne], vol 76 n° 1 (March 2019)  

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GNSS ionospheric TEC and positioning accuracy during intense space and terrestrial weather events in B&H / Randa Natraš in Geodetski vestnik, vol 63 n° 1 (March - May 2019)  

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LiDAR, a technology to assist with smart cities and climate change resilience: a case study in an urban metropolis / Ryan Garnett in ISPRS International journal of geo-information, vol 7 n° 5 (May 2018)  

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Precipitable water vapour content from ESR/SKYNET sun–sky radiometers : validation against GNSS/GPS and AERONET over three different sites in Europe / Monica Campanelli in Atmospheric measurement techniques, vol 11 n° 1 (January 2018)    

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A study of the influence of the historical snow accumulation and wind effects on the extended Chajnantor plateau / Juliette Ortet (2018) 

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Identification of rainwater harvesting sites using SCS-CN methodology, remote sensing and Geographical Information System techniques / Tarun Kumar in Geocarto international, vol 32 n° 12 (December 2017)  

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Effects of using different sources of remote sensing and geographic information system data on urban stormwater 2D–1D modeling / Yi Hong in Applied sciences, vol 7 n° 9 (September 2017)  

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Statistical comparison and combination of GPS, GLONASS, and multi-GNSS multipath reflectometry applied to snow depth retrieval / Sajad Tabibi in IEEE Transactions on geoscience and remote sensing, vol 55 n° 7 (July 2017)  

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Recent growth changes in Western European forests are driven by climate warming and structured across tree species climatic habitats / Marie Charru in Annals of Forest Science [en ligne], vol 74 n° 2 (June 2017)  

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Frequency of extreme Sahelian storms tripled since 1982 in satellite observations / Christopher M. Taylor in Nature letters, vol 544 n° 7651 (27 April 2017)  

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