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Continental mass change from GRACE over 2002–2011 and its impact on sea level / O. Baur in Journal of geodesy, vol 87 n° 2 (February 2013)
[article]
Titre : Continental mass change from GRACE over 2002–2011 and its impact on sea level Type de document : Article/Communication Auteurs : O. Baur, Auteur ; M. Kuhn, Auteur ; Will E. Featherstone, Auteur Année de publication : 2013 Article en page(s) : pp 117 - 125 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] analyse diachronique
[Termes IGN] continent
[Termes IGN] données GRACE
[Termes IGN] eau de fonte
[Termes IGN] géocentre
[Termes IGN] levé gravimétrique
[Termes IGN] masse de la Terre
[Termes IGN] niveau de la mer
[Termes IGN] niveau moyen des mers
[Termes IGN] variationRésumé : (Auteur) Present-day continental mass variation as observed by space gravimetry reveals secular mass decline and accumulation. Whereas the former contributes to sea-level rise, the latter results in sea-level fall. As such, consideration of mass accumulation (rather than focussing solely on mass loss) is important for reliable overall estimates of sea-level change. Using data from the Gravity Recovery And Climate Experiment satellite mission, we quantify mass-change trends in 19 continental areas that exhibit a dominant signal. The integrated mass change within these regions is representative of the variation over the whole land areas. During the integer 9-year period of May 2002 to April 2011, GIA-adjusted mass gain and mass loss in these areas contributed, on average, to -(0.7 + 0.4) mm/year of sea-level fall and + (1.8 + 0.2) mm/year of sea-level rise; the net effect was + (1.1 + 0.6) mm/year. Ice melting over Greenland, Iceland, Svalbard, the Canadian Arctic archipelago, Antarctica, Alaska and Patagonia was responsible for + (1.4+0.2) mm/year of the total balance. Hence, land-water mass accumulation compensated about 20 % of the impact of ice-melt water influx to the oceans. In order to assess the impact of geocentre motion, we converted geocentre coordinates derived from satellite laser ranging (SLR) to degree-one geopotential coefficients. We found geocentre motion to introduce small biases to mass-change and sea-level change estimates; its overall effect is + (0.1 + 0.1) mm/year. This value, however, should be taken with care owing to questionable reliability of secular trends in SLR-derived geocentre coordinates. Numéro de notice : A2013-098 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-012-0583-2 Date de publication en ligne : 14/07/2012 En ligne : https://doi.org/10.1007/s00190-012-0583-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32236
in Journal of geodesy > vol 87 n° 2 (February 2013) . - pp 117 - 125[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2013021 SL Revue Centre de documentation Revues en salle Disponible A multi-scale approach to mapping canopy height / Gordon M. Green in Photogrammetric Engineering & Remote Sensing, PERS, vol 79 n° 2 (February 2013)
[article]
Titre : A multi-scale approach to mapping canopy height Type de document : Article/Communication Auteurs : Gordon M. Green, Auteur ; C. Ahearn, Auteur ; W. Ni-Meister, Auteur Année de publication : 2013 Article en page(s) : pp 185 - 194 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] analyse multiéchelle
[Termes IGN] base de données d'occupation du sol
[Termes IGN] carte de la végétation
[Termes IGN] données altimétriques
[Termes IGN] données ICEsat
[Termes IGN] données laser
[Termes IGN] Etats-Unis
[Termes IGN] fusion de données
[Termes IGN] hauteur de la végétation
[Termes IGN] occupation du sol
[Termes IGN] service web géographiqueRésumé : (Auteur) Mapping vegetation height over large areas presents a problem of scale: height varies with the individual tree or stand, but the resolution of available datasets is too low to characterize this variability sufficiently for many applications. We address this problem by fusing 1 km resolution canopy height data derived from satellite-based laser altimetry with higher-resolution land-cover data, resulting in 30 m resolution estimates of canopy height. These are downscaled further to 1 m resolution by simulating individual trees. A web service architecture is used, which allows processing to occur on demand without preprocessing large datasets. We compared the resulting canopy volumes to reference airborne lidar data from 262 randomly located 1 km2 areas within nine study sites. Results at 30 m resolution show an RMSE of 33 percent of the mean reference volume and an R2 of 0.77; at 1 m the RMSE is 66 percent and the R2 is 0.38. Numéro de notice : A2013-078 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.14358/PERS.79.2.185 En ligne : https://doi.org/10.14358/PERS.79.2.185 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32216
in Photogrammetric Engineering & Remote Sensing, PERS > vol 79 n° 2 (February 2013) . - pp 185 - 194[article]Spatially variable surface elevation changes and estimated melt water contribution of Continental Glacier in the Wind River Range, Wyoming, USA, 1966-2011 / Jeffrey A. Vanlooy in Geocarto international, vol 28 n° 1-2 (February - May 2013)
[article]
Titre : Spatially variable surface elevation changes and estimated melt water contribution of Continental Glacier in the Wind River Range, Wyoming, USA, 1966-2011 Type de document : Article/Communication Auteurs : Jeffrey A. Vanlooy, Auteur ; Richard R. Forster, Auteur ; David Barta, Auteur ; James Turrin, Auteur Année de publication : 2013 Article en page(s) : pp 98 - 113 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] analyse diachronique
[Termes IGN] bassin hydrographique
[Termes IGN] données altimétriques
[Termes IGN] eau de fonte
[Termes IGN] glacier
[Termes IGN] Wyoming (Etats-Unis)Résumé : (Auteur) Seasonal snow melt in the Wind River Range, Wyoming, has been ending earlier over the last several decades leaving the region to rely more on supplemental melt water from mountain glaciers. This leads to the necessity of understanding recent glacial changes. This study uses elevation data from 1966, 2006 and 2011 to calculate surface elevation and volume changes that have occurred on Continental Glacier. Results indicate a mean volume change of -0.034 1 0.02 km3 and surface elevation change of -0.36 1 0.19 m y-1 between 1966 and 2006. Detailed spatial analysis shows that the glacier is divided into two sections which are thinning at different rates (lower section: -0.0610.19 m y-1; upper section: -0.51 1 0.19 m y-1). The upper section has experienced 97% of the thinning (or 742.5 * 103 m3 of melt water equivalent per year) and increased its rate since 2006 by 27.5%. Numéro de notice : A2013-277 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2012.665500 Date de publication en ligne : 05/03/2012 En ligne : https://doi.org/10.1080/10106049.2012.665500 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32415
in Geocarto international > vol 28 n° 1-2 (February - May 2013) . - pp 98 - 113[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2013011 RAB Revue Centre de documentation En réserve L003 Disponible Comparison of grid averaged altimeter and buoy significant wave heights in the Northern Indian Ocean / L. Sabique in Marine geodesy, vol 36 n° 1 (January - March 2013)
[article]
Titre : Comparison of grid averaged altimeter and buoy significant wave heights in the Northern Indian Ocean Type de document : Article/Communication Auteurs : L. Sabique, Auteur ; T. Balakrishnan Nair, Auteur ; K. Srinivas, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 72 - 85 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] altimétrie satellitaire par radar
[Termes IGN] analyse diachronique
[Termes IGN] AVISO
[Termes IGN] bouée
[Termes IGN] bouée dérivante
[Termes IGN] cyclone
[Termes IGN] hauteurs de mer
[Termes IGN] Indien (océan)
[Termes IGN] série temporelle
[Termes IGN] vagueRésumé : (Auteur) A quantitative comparison of the collocated inter-annual significant wave height (SWH) data collected between 2006 and 2009 from buoys and altimeters at nine buoy locations (total n = 2241) in the Northern Indian Ocean is attempted for assessing the validity of daily averaged gridded altimeter significant wave height (ASWH) provided by AVISO for operational use. ASWH is underestimated by 0.20 m, the root-mean-square error (RMSE) is less than 0.30 m, the Scatter Index is less than 20%, and the correlation coefficient is greater than 0.90. Further, at three locations, the examination of the above statistics showed that the bias and RMSE is high during the southwest monsoon season compared with the Northeast monsoon. Scatter Index showed only slight variation (14–18%) for different ranges of SWH. The response of the daily average gridded ASWH data during extreme conditions (cyclones) in the vicinity of the buoy locations is poor at all compared buoy locations. The gridded ASWH from different satellite missions provided by AVISO can be used for basin scale validation experiments of the wave model and for climatological studies in the Indian Ocean, except during cyclone conditions. Numéro de notice : A2013-246 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1080/01490419.2012.743493 Date de publication en ligne : 13/03/2013 En ligne : https://doi.org/10.1080/01490419.2012.743493 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32384
in Marine geodesy > vol 36 n° 1 (January - March 2013) . - pp 72 - 85[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 230-2013011 RAB Revue Centre de documentation En réserve L003 Disponible Global height system unification with GOCE: a simulation study on the indirect bias term in the GBVP approach / C. Gerlach in Journal of geodesy, vol 87 n° 1 (January 2013)
[article]
Titre : Global height system unification with GOCE: a simulation study on the indirect bias term in the GBVP approach Type de document : Article/Communication Auteurs : C. Gerlach, Auteur ; Reiner Rummel, Auteur Année de publication : 2013 Article en page(s) : pp 57 - 67 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] altitude
[Termes IGN] anomalie de pesanteur
[Termes IGN] données GOCE
[Termes IGN] erreur systématique
[Termes IGN] géoïde gravimétrique
[Termes IGN] géoïde terrestre
[Termes IGN] harmonique sphérique
[Termes IGN] hauteur ellipsoïdale
[Termes IGN] modèle de géopotentiel
[Termes IGN] problème des valeurs limites
[Termes IGN] résidu
[Termes IGN] système de référence altimétriqueRésumé : (Auteur) One of the main objectives of ESA’s Gravity Field and Steady-State Ocean Circulation mission GOCE (Gravity field and steady-state ocean circulation mission, 1999) is to allow global unification of height systems by directly providing potential differences between benchmarks in different height datum zones. In other words, GOCE provides a globally consistent and unbiased geoid. If this information is combined with ellipsoidal (derived from geodetic space techniques) and physical heights (derived from leveling/gravimetry) at the same benchmarks, datum offsets between the datum zones can be determined and all zones unified. The expected accuracy of GOCE is around 2–3 cm up to spherical harmonic degree nmax ~ 200. The omission error above this degree amounts to about 30 cm which cannot be neglected. Therefore, terrestrial residual gravity anomalies are necessary to evaluate the medium and short wavelengths of the geoid, i.e. one has to solve the Geodetic Boundary Value Problem (GBVP). The theory of height unification by the GBVP approach is well developed, see e.g. Colombo (A World Vertical Network. Report 296, Department of Geodetic Science and Surveying, 1980) or Rummel and Teunissen (Bull Geod 62:477–498, 1988). Thereby, it must be considered that terrestrial gravity anomalies referring to different datum zones are biased due to the respective datum offsets. Consequently, the height reference surface of a specific datum zone deviates from the unbiased geoid not only due to its own datum offset (direct bias term) but is also indirectly affected by the integration of biased gravity anomalies. The latter effect is called the indirect bias term and it considerably complicates the adjustment model for global height unification. If no satellite based gravity model is employed, this error amounts to about the same size as the datum offsets, i.e. 1–2 m globally. We show that this value decreases if a satellite-only gravity model is used. Specifically for GOCE with nmax ~ 200, the error can be expected not to exceed the level of 1 cm, allowing the effect to be neglected in practical height unification. The results are supported by recent findings by Gatti et al. (J Geod, 2012). Numéro de notice : A2013-074 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-012-0579-y En ligne : https://doi.org/10.1007/s00190-012-0579-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32212
in Journal of geodesy > vol 87 n° 1 (January 2013) . - pp 57 - 67[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2013011 SL Revue Centre de documentation Revues en salle Disponible Lowest astronomical tide in the North Sea derived from a vertically referenced shallow water model, and an assessment of its suggested sense of safety / D. Slobbe in Marine geodesy, vol 36 n° 1 (January - March 2013)PermalinkPhilippe de La Hire, 1640-1718, entre architecture et sciences / Antonio Becchi (2013)PermalinkSciences of geodesy, vol 2. Innovations and future developments / Guochang Xu (2013)PermalinkPermalinkThe height datum problem and the role of satellite gravity models / A. Gatti in Journal of geodesy, vol 87 n° 1 (January 2013)PermalinkPermalinkEDM calibration and finding errors in the baseline / D. C. Annunciation in SaLIS Surveying and land information science, vol 72 n° 4 (December 2012)PermalinkGIS-based modeling of sea level rise effect on coastal property management policies / C. A. Nettleman in SaLIS Surveying and land information science, vol 72 n° 4 (December 2012)PermalinkMitigating the effects of vertical land motion in tide gauge records using a state-of-the-art GPS velocity field / Alvaro Santamaria Gomez in Global and Planetary Change, vol 98 - 99 (December 2012)PermalinkNontidal ocean loading: amplitudes and potential effects in GPS height time series / Tonie M. van Dam in Journal of geodesy, vol 86 n° 11 (November 2012)Permalink