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Assessing the effect of snow/water obstructions on the measurement of tree seedlings in a large-scale temperate forest inventory / C. W. Woodall in Forestry, an international journal of forest research, vol 86 n° 4 (October 2013)
[article]
Titre : Assessing the effect of snow/water obstructions on the measurement of tree seedlings in a large-scale temperate forest inventory Type de document : Article/Communication Auteurs : C. W. Woodall, Auteur ; James A. Westfall, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 421 - 427 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Etats-Unis
[Termes IGN] forêt tempérée
[Termes IGN] impact sur les données
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] neige
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) National-scale forest inventories have endeavoured to include holistic measurements of forest health inclusive of attributes such as downed dead wood and tree regeneration that occur in the forest understory. Inventories may require year-round measurement of inventory plots with some of these measurements being affected by seasonal obstructions (e.g. snowpacks and seasonal flooding). In order to assess the potential effects that snow/water obstructions may have on the measurement/analysis of forest seedlings across large scales, the differences in seedling abundance between two inventory measurements (∼5-year remeasurement period) and as affected by snow/water depth was ascertained using a repeated forest inventory across the eastern US. Results indicate that there is a general trend of decreasing seedling density over time (−33.16 seedlings ha−1 year−1) in the eastern US, with snow/water depths in excess of 15 cm significantly affecting resulting estimates of seedling abundance. Although snow/water obstruction to seedling measurement occurred on ∼9 per cent of inventory plots across the eastern US, snow was a much more common situation occurring on nearly 50 per cent of plots (at time 1, 2 or both) at high latitudes (>45°). Given the statistically significant effect of snow/water on seedling abundance estimates, tree regeneration assessments should not include observations obstructed by snow/water depths that exceed minimum seedling heights. Furthermore, seedling abundance inventories may mitigate the influence of measurement obstructions by sampling only during the summer or incorporating climate information into their sampling logistics. Numéro de notice : A2013-788 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1093/forestry/cpt013 En ligne : https://doi.org/10.1093/forestry/cpt013 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78312
in Forestry, an international journal of forest research > vol 86 n° 4 (October 2013) . - pp 421 - 427[article]Monitoring seasonal snow dynamics using ground based high resolution photography (Austre Lovénbreen, Svalbard, 79°N) / Etienne Bernard in ISPRS Journal of photogrammetry and remote sensing, vol 75 (January 2013)
[article]
Titre : Monitoring seasonal snow dynamics using ground based high resolution photography (Austre Lovénbreen, Svalbard, 79°N) Type de document : Article/Communication Auteurs : Etienne Bernard , Auteur ; J.M. Friedt, Auteur ; F. Tolle, Auteur ; M. Laffly, Auteur ; C. Marlin, Auteur Année de publication : 2013 Article en page(s) : pp 92 - 100 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse diachronique
[Termes IGN] changement climatique
[Termes IGN] données localisées
[Termes IGN] glacier
[Termes IGN] image terrestre
[Termes IGN] neige
[Termes IGN] surveillance météorologique
[Termes IGN] SvalbardRésumé : (Auteur) Arctic glaciers are reliable indicators of global climate changes. However, monitoring snow and ice dynamics in Arctic regions is challenging: some fast but key events can be missed since they are short in time but significant in the hydrological budget. In the context of long term monitoring with high temporal and spatial resolutions of the snow cover dynamics, automated digital cameras were installed around the Austre Lovénbreen glacier basin (Spitsbergen, Norway, 79°N). Despite data losses due to rough weather conditions and control electronics failure, a dataset of 2411 pictures (out of an expected 3294) was gathered over a 1 year hydrological period to assess the snow coverage of the glacier as a function of time with daily resolution. 73% of the total number of expected images was thus recorded, with gaps associated with temporary electronics or data storage failure. The six camera stations oriented so as to observe the glacier itself provide a surface coverage of 96%. Furthermore, geometric corrections of the pictures, using reference ground control points located on the glacier through GPS receivers, yield a quantitative information from initially qualitative images. Projecting the resulting mosaic of the images gathered from six cameras on a GIS allows for the precise monitoring of ice-related processes, and especially the snow coverage evolution over time. This paper summarizes our current understanding of such dynamics, based on the analysis of daily mosaics of images allowing for the observation of both long term evolution on the seasonal scale and the short term events on a weekly scale. Such results demonstrated over one typical full hydrological season (April–October 2009) that snow coverage evolves following discrete steps, either due to water precipitation or warm events, with a snow coverage ranging from 100% (april) to 37% (September). Numéro de notice : A2013-035 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2012.11.001 En ligne : https://doi.org/10.1016/j.isprsjprs.2012.11.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32173
in ISPRS Journal of photogrammetry and remote sensing > vol 75 (January 2013) . - pp 92 - 100[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2013011 RAB Revue Centre de documentation En réserve L003 Disponible GPS snow depth meter with geometry-free linear combinations of carrier phases / M. Ozeki in Journal of geodesy, vol 86 n° 3 (March 2012)
[article]
Titre : GPS snow depth meter with geometry-free linear combinations of carrier phases Type de document : Article/Communication Auteurs : M. Ozeki, Auteur ; K. Heki, Auteur Année de publication : 2012 Article en page(s) : pp 209 - 217 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] antenne GPS
[Termes IGN] combinaison linéaire
[Termes IGN] Hokkaido (Japon)
[Termes IGN] neige
[Termes IGN] phase GPS
[Termes IGN] rapport signal sur bruit
[Termes IGN] traitement de données GNSS
[Termes IGN] trajet multipleRésumé : (Auteur) Multipath in global positioning system (GPS) is the interference of the microwave signals directly from satellites and those reflected before reaching the antenna, typically by the ground. Because reflected signals cause positioning errors, GPS antennas are designed to reduce such interference. Recent studies show that multipath could be utilized to infer the properties of the ground around the antenna. Here, we report one such application, i.e. a fixed GPS station used as a snow depth meter. Because the satellite moves in the sky, the excess path length of reflected waves changes at rates dependent on the antenna height. This causes quasi-periodic variations of the amplitude and phase of the received signals. Accumulation of snow reduces effective antenna heights, and we can see it by analyzing multipath signatures. Signal-to-noise ratios (SNR) are often used to analyze multipath, but they are not always available in raw GPS data files. Here, we demonstrate that the geometry-free linear combination (L4), normally used to study the ionosphere, can also be used to analyze multipath signatures. We obtained snow depth time series at a GPS station in Hokkaido, Japan, from January to April in 2009 using L4 and SNR. Then, we compared their precisions. We also discuss mechanisms responsible for the possible underestimation of the snow depth by GPS. Finally, we investigate the possibility of inferring physical conditions of the snow surface using amplitudes of multipath signatures. Numéro de notice : A2012-150 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-011-0511-x Date de publication en ligne : 14/09/2011 En ligne : https://doi.org/10.1007/s00190-011-0511-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31597
in Journal of geodesy > vol 86 n° 3 (March 2012) . - pp 209 - 217[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2012031 RAB Revue Centre de documentation En réserve L003 Disponible
Titre : Remote sensing of planet earth Type de document : Monographie Auteurs : Yann Chemin, Éditeur scientifique Editeur : London [UK] : IntechOpen Année de publication : 2012 Importance : 252 p. Format : 18 x 26 cm ISBN/ISSN/EAN : 978-953-51-4940-8 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] classification dirigée
[Termes IGN] classification par maximum de vraisemblance
[Termes IGN] distribution spatiale
[Termes IGN] géomorphologie
[Termes IGN] image satellite
[Termes IGN] neige
[Termes IGN] occupation du sol
[Termes IGN] surveillance géologique
[Termes IGN] système d'information géographiqueRésumé : (éditeur) Monitoring of water and land objects enters a revolutionary age with the rise of ubiquitous remote sensing and public access. Earth monitoring satellites permit detailed, descriptive, quantitative, holistic, standardized, global evaluation of the state of the Earth skin in a manner that our actual Earthen civilization has never been able to before. The water monitoring topics covered in this book include the remote sensing of open water bodies, wetlands and small lakes, snow depth and underwater seagrass, along with a variety of remote sensing techniques, platforms, and sensors. The Earth monitoring topics include geomorphology, land cover in arid climate, and disaster assessment after a tsunami. Finally, advanced topics of remote sensing covers atmosphere analysis with GNSS signals, earthquake visual monitoring, and fundamental analyses of laser reflectometry in the atmosphere medium. Note de contenu : 1- On the Use of Airborne Imaging Spectroscopy Data for the Automatic Detection and Delineation of Surface Water Bodies
2- Remote Sensing for Mapping and Monitoring Wetlands and Small Lakes in Southeast Brazil
3- Satellite-Based Snow Cover Analysis and the Snow Water Equivalent Retrieval Perspective over China
4- Seagrass Distribution in China with Satellite Remote Sensing
5- The Use of Remote Sensed Data and GIS to Produce a Digital Geomorphological Map of a Test Area in Central Italy
6- Analysis of Land Cover Classification in Arid Environment: A Comparison Performance of Four Classifiers
7- Application of Remote Sensing for Tsunami Disaster
8- GNSS Signals: A Powerful Source for Atmosphere and Earth’s Surface Monitoring
9- Acceleration Visualization Marker Using Moiré Fringe for Remote Sensing
10- Looking at Remote Sensing the Timing of an Organisation's Point of View and the Anticipation of Today's ProblemsNuméro de notice : 25880 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Recueil / ouvrage collectif DOI : 10.5772/2291 En ligne : https://doi.org/10.5772/2291 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95735 vol 31 n° 14 - July 2010 - Special issue : satellite-based observations of hydrologycal process (Bulletin de International Journal of Remote Sensing IJRS) / Remote sensing and photogrammetry society
[n° ou bulletin]
est un bulletin de International Journal of Remote Sensing IJRS / Remote sensing and photogrammetry society (1980 -)
Titre : vol 31 n° 14 - July 2010 - Special issue : satellite-based observations of hydrologycal process Type de document : Périodique Auteurs : Remote sensing and photogrammetry society, Auteur Année de publication : 2010 Importance : 404 p. Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] évapotranspiration
[Termes IGN] humidité du sol
[Termes IGN] hydrologie
[Termes IGN] neigeNuméro de notice : 080-201009 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Numéro de périodique Permalink : https://documentation.ensg.eu/index.php?lvl=bulletin_display&id=9953 [n° ou bulletin]Contient
- Evaluation of a satellite-based global flood monitoring system / K. Yilmaz in International Journal of Remote Sensing IJRS, vol 31 n° 14 (July 2010)
- Land cover characterization for hydrological modelling using thermal infrared emissivities / A. French in International Journal of Remote Sensing IJRS, vol 31 n° 14 (July 2010)
- Evaluating terrestrial water storage variations from regionally constrained GRACE mascon data and hydrological models over Southern Africa: preliminary results / P. Krogh in International Journal of Remote Sensing IJRS, vol 31 n° 14 (July 2010)
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Code-barres Cote Support Localisation Section Disponibilité 080-2010091 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Snow permitivity retrieval inversion algorithm for estimating snow wetness / G. Singh in Geocarto international, vol 25 n° 3 (June 2010)PermalinkGNSS-R [GNSS-Reflectometry]: a space asset for non-space applications / A. Egido in Geoinformatics, vol 12 n° 6 (01/09/2009)PermalinkComparison of space borne radar altimetry and airborne laser altimetry over sea ice in the Fram Strait / K.A. Giles in International Journal of Remote Sensing IJRS, vol 27 n°15-16 (August 2006)PermalinkHochgenaue Generierung des DGM vom vergletscherten Hochgebirge : Potential von airborne Laserscanning / D. Lenhart (2006)PermalinkPotentiel des données ASAR-Envisat en bande C pour la détermination des caractéristiques de la neige humide en environnement alpin / Jean-Pierre Dedieu in Revue Française de Photogrammétrie et de Télédétection, n° 179 (Décembre 2005)PermalinkSnow cover monitoring in Alpine regions using ENVISAT optical data / M. Pepe in International Journal of Remote Sensing IJRS, vol 26 n° 21 (November 2005)PermalinkDerivation of a threshold function for the advanced very high resolution radiometer 3, 75um channel and its application in automatic cloud discrimination over snow/ice surfaces / X. Xiong in International Journal of Remote Sensing IJRS, vol 25 n° 15 (August 2004)PermalinkArtificial neural network-based techniques for the retrieval of SWE [snow water equivalent] and snow depth from SSM/I data / Marco Tedesco in Remote sensing of environment, vol 90 n° 1 (15/03/2004)PermalinkEstimating fractional snow cover from MODIS using the normalized difference snow index / V.V. Salomonson in Remote sensing of environment, vol 89 n° 3 (15/02/2004)PermalinkNarrowband-to-broadband albedo conversion for glacier ice and snow: equations based on modeling and ranges of validity of the equations / W. Greuell in Remote sensing of environment, vol 89 n° 1 (15/01/2004)Permalink