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A new computerized ionosphere tomography model using the mapping function and an application to the study of seismic-ionosphere disturbance / Jian Kong in Journal of geodesy, vol 90 n° 8 (August 2016)
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Titre : A new computerized ionosphere tomography model using the mapping function and an application to the study of seismic-ionosphere disturbance Type de document : Article/Communication Auteurs : Jian Kong, Auteur ; Yi Bin Yao, Auteur ; Lei Liu, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 741 – 755 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] altération
[Termes IGN] correction troposphérique
[Termes IGN] International Reference Ionosphere
[Termes IGN] Japon
[Termes IGN] séisme
[Termes IGN] teneur totale en électrons
[Termes IGN] tomographie
[Termes IGN] troposphèreRésumé : (auteur) A new algorithm for ionosphere tomography using the mapping function is proposed in this paper. First, the new solution splits the integration process into four layers along the observation ray, and then, the single-layer model (SLM) is applied to each integration part using a mapping function. Next, the model parameters are estimated layer by layer with the Kalman filtering method by introducing the scale factor (SF) γ to solve the ill-posed problem. Finally, the inversed images of different layers are combined into the final CIT image. We utilized simulated data from 23 IGS GPS stations around Europe to verify the estimation accuracy of the new algorithm; the results show that the new CIT model has better accuracy than the SLM in dense data areas and the CIT residuals are more closely grouped. The stability of the new algorithm is discussed by analyzing model accuracy under different error levels (the max errors are 5TECU, 10TECU, 15TECU, respectively). In addition, the key preset parameter, SFγ, which is given by the International Reference Ionosphere model (IRI2012). The experiment is designed to test the sensitivity of the new algorithm to SF variations. The results show that the IRI2012 is capable of providing initial SF values. Also in this paper, the seismic-ionosphere disturbance (SID) of the 2011 Japan earthquake is studied using the new CIT algorithm. Combined with the TEC time sequence of Sat.15, we find that the SID occurrence time and reaction area are highly related to the main shock time and epicenter. According to CIT images, there is a clear vertical electron density upward movement (from the 150-km layer to the 450-km layer) during this SID event; however, the peak value areas in the different layers were different, which means that the horizontal movement velocity is not consistent among the layers. The potential physical triggering mechanism is also discussed in this paper. Compared with the SLM, the RMS of the new CIT model is improved by 16.78%, while the CIT model could provide the three-dimensional variation in the ionosphere. Numéro de notice : A2016-504 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-016-0906-9 En ligne : http://dx.doi.org/10.1007/s00190-016-0906-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81528
in Journal of geodesy > vol 90 n° 8 (August 2016) . - pp 741 – 755[article]A seamless weather–climate multi‐model intercomparison on the representation of a high impact weather event in the western Mediterranean: HyMeX IOP12 / Samiro Khodayar in Quarterly Journal of the Royal Meteorological Society, vol 142 n° S1 (August 2016)
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Titre : A seamless weather–climate multi‐model intercomparison on the representation of a high impact weather event in the western Mediterranean: HyMeX IOP12 Type de document : Article/Communication Auteurs : Samiro Khodayar, Auteur ; G. Fosser, Auteur ; S. Berthou, Auteur ; Silvio Davolio, Auteur ; Philippe Drobinski, Auteur ; Véronique Ducrocq, Auteur ; Rossella Ferretti, Auteur ; Mathieu Nuret, Auteur ; E. Pichelli, Auteur ; Evelyne Richard, Auteur ; Olivier Bock , Auteur
Année de publication : 2016 Projets : HyMeX / Richard, Evelyne Article en page(s) : pp 433 - 452 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] analyse comparative
[Termes IGN] bassin méditerranéen
[Termes IGN] climat méditerranéen
[Termes IGN] convection
[Termes IGN] distribution spatiale
[Termes IGN] données météorologiques
[Termes IGN] humidité de l'air
[Termes IGN] modèle météorologique
[Termes IGN] précipitation
[Termes IGN] vapeur d'eau
[Termes IGN] variabilitéRésumé : (auteur) High Impact Weather (HIW), particularly Heavy Precipitation Events (HPE), are common phenomena affecting the western Mediterranean (WMED) especially in the autumn period. Understanding and evaluating the capability to adequately represent such events in model simulations is one of the main goals of the Hydrological cycle in the Mediterranean Experiment (HyMeX) and the main motivation of this investigation.
In order to gain a better knowledge of the model representation of HPE and related processes we perform a seamless multi‐model intercomparison at the event scale. Limited‐area model runs (grid spacing from 2 to 20 km) at weather and climate time‐scales are considered, four with parametrized and five with explicit convection. The performance of the nine models is compared by analysing precipitation, as well as convection‐relevant parameters. An Intensive Observation Period (IOP12) from the HyMeX‐SOP1 (Special Observation Period) is used to illustrate the results. During IOP12, HPE affected the northwestern Mediterranean region, from Spain to Italy, as a consequence of Mesoscale Convective Systems (MCSs) which initiated and intensified in the area of investigation. Results show that: (i) the timing of the maximum precipitation seems to be linked to the representation of large‐scale conditions rather than differences among models; (ii) Convection Permitting Models (CPMs) exhibit differences among each other, but better represent the short‐intense convective events. All four convection‐parametrized models produce a large number of weak and long‐lasting events. Regional Climate Models (RCMs) capture the occurrence of the event but produce notably lower precipitation amounts and hourly intensities than CPMs and Numerical Weather Prediction (NWP) models with parametrized convection; (iii) these differences do not seem to come from mean moisture or Convective Available Potential Energy (CAPE) which are in the same range for all models, but rather from differences in the variability and vertical distribution of moisture and the triggering of deep convection.Numéro de notice : A2016--174 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1002/qj.2700 Date de publication en ligne : 29/10/2015 En ligne : https://doi.org/10.1002/qj.2700 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91787
in Quarterly Journal of the Royal Meteorological Society > vol 142 n° S1 (August 2016) . - pp 433 - 452[article]Silvicultural climatic turning point for European beech and sessile oak in Western Europe derived from national forest inventories / Klara Dolos in Forest ecology and management, vol 373 (1 August 2016)
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Titre : Silvicultural climatic turning point for European beech and sessile oak in Western Europe derived from national forest inventories Type de document : Article/Communication Auteurs : Klara Dolos, Auteur ; Tobias Mette, Auteur ; Camilla Wellstein, Auteur Année de publication : 2016 Article en page(s) : pp 128 - 137 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Allemagne
[Termes IGN] analyse diachronique
[Termes IGN] changement climatique
[Termes IGN] Fagus sylvatica
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] inventaire forestier national (données France)
[Termes IGN] modèle statistique
[Termes IGN] peuplement mélangé
[Termes IGN] Quercus sessiliflora
[Termes IGN] sol forestier
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) Forests of temperate Europe are climate sensitive ecosystems, and the current balance between the tree species will shift as climate becomes warmer and potentially drier. Especially changes in the dominant species have a strong impact on forest ecosystems because they fundamentally change life conditions of plants and animals living in the forest. Mette et al. (2013) introduced the climatic turning point (CTP) as a concept that marks the climatic conditions where such a change in species dominance is expected to occur. While they modelled the CTP for European beech (Fagus sylvatica) and sessile oak (Quercus petraea) from environmentally sensitive forest growth models, this study determined the CTP between beech and oak from national forest inventories in Western Europe. We ask (1) under which climate conditions the inventory-based CTP occurs, (2) whether it is modified by soil type and (3) how it differs from other CTP references like the Ellenberg quotient (Ellenberg, 1963). The CTP from beech to oak occurred approximately at mean annual temperatures above 8–9 °C if annual precipitation was below 600 mm and rose to 11–12 °C for annual precipitation exceeding 900 mm. This relation was strongly modified by soil type. Compared to Ellenberg (1963) and Mette et al. (2013), oak replaced beech at far more moderate climatic conditions (EQ 20–30). This can be attributed to the silvicultural history of forest stands: the inventory-based CTP signal carries the century old anthropogenic preference for oak. We expand the CTP concept that was until now based on natural competition by a “silvicultural” CTP that is contained in large-scale inventory data. It thereby implicitly incorporates the question how silviculture and social-cultural values impact the balance between species. Climate change projections indeed suggested that large parts of Western Europe will cross the silvicultural CTP. Numéro de notice : A2016--203 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1016/j.foreco.2016.04.018 Date de publication en ligne : 27/04/2016 En ligne : https://doi.org/10.1016/j.foreco.2016.04.018 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96040
in Forest ecology and management > vol 373 (1 August 2016) . - pp 128 - 137[article]The variability of water vapour and pre-convective conditions over the mountainous island of Corsica / Bianca Adler in Quarterly Journal of the Royal Meteorological Society, vol 142 n° S1 (August 2016)
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Titre : The variability of water vapour and pre-convective conditions over the mountainous island of Corsica Type de document : Article/Communication Auteurs : Bianca Adler, Auteur ; Norbert Kalthoff, Auteur ; Martin Kohler, Auteur ; Jan Handwerker, Auteur ; Andreas Wieser, Auteur ; Ulrich Corsmeier, Auteur ; Christoph Kottmeier, Auteur ; Dominique Lambert, Auteur ; Olivier Bock , Auteur
Année de publication : 2016 Projets : HyMeX / Richard, Evelyne Article en page(s) : pp 335 - 346 Note générale : biblographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] circulation atmosphérique
[Termes IGN] convection
[Termes IGN] coordonnées GPS
[Termes IGN] Corse
[Termes IGN] couche atmosphérique
[Termes IGN] données météorologiques
[Termes IGN] teneur intégrée en vapeur d'eauRésumé : (auteur) Comprehensive measurements were carried out on the mountainous island of Corsica during the Hydrological cycle in the Mediterranean Experiment (HyMeX) field campaign in 2012. Using data from an operational GPS network, radiosondes and microwave radiometers, we studied the spatio-temporal variability of integrated water vapour (IWV) and convection-related parameters in the pre-convective environment over the island. The following spatial differences in the IWV evolution occurred frequently. In the interior of the island the IWV strongly increased around noon, while on the upstream coast only small variations were observed. We showed that a transport of water vapour with thermally driven circulations and the formation of elevated humidity layers due to advective venting caused the diurnal IWV variation over and downstream of the mountains. Spatial inhomogeneities in the pre-convective atmospheric conditions evolved and the knowledge of these turned out to be crucial to understanding the timing and location of isolated deep convection over the island. Numéro de notice : A2016-937 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1002/qj.2545 Date de publication en ligne : 04/03/2015 En ligne : http://dx.doi.org/10.1002/qj.2545 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83290
in Quarterly Journal of the Royal Meteorological Society > vol 142 n° S1 (August 2016) . - pp 335 - 346[article]Assessment and validation of evapotranspiration using SEBAL algorithm and Lysimeter data of IARI agricultural farm, India / Anju Bala in Geocarto international, vol 31 n° 7 - 8 (July - August 2016)
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Titre : Assessment and validation of evapotranspiration using SEBAL algorithm and Lysimeter data of IARI agricultural farm, India Type de document : Article/Communication Auteurs : Anju Bala, Auteur ; Kishan Singh Rawat, Auteur ; Anil Kumar Misra, Auteur Année de publication : 2016 Article en page(s) : pp 739 - 764 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] analyse diachronique
[Termes IGN] évapotranspiration
[Termes IGN] humidité du sol
[Termes IGN] image Landsat-ETM+
[Termes IGN] Inde
[Termes IGN] production agricole
[Termes IGN] teneur en eau de la végétationRésumé : (Auteur) Evapotranspiration (ET) is a vital process in land surface atmosphere research. In this study, Surface Energy Balance Algorithm for Land (SEBAL) for the assessment of ET (for 23 December 2010, 8 January 2011, 24 January 2011, 9 February 2011, 25 February 2011, 29 March 2011 and 14 April 2011) from LANDSAT7-ETM+ and validation with Lysimeter data set is illustrated. It is based on the evaporative fraction concept, and it has been applied to LANDSAT7-ETM + (30 m resolution) data acquired over the Indian Agricultural Research Institute’s agricultural farm land. The ET from SEBAL was compared with Lysimeter ET using four statistical tests (root-mean-square error (RMSE), relative root-mean-square error (R-RMSE), mean absolute error (MAE), and normalized root-mean square error (NRMSE)), and each test showed a good correlation between the predicted and observed ET values. Results from this study revealed that the RMSE of crop-growing period was 0.51 mm d−1 for ETSEBAL, i.e. ETSEBAL having good accuracy with respect to observed ETLysimeter. Results were also validated using R-RMSE test, which also proved that ETSEBAL data are having good accuracy with respect to observed ETLysimeter as R-RMSE of crop-growing period is 0.19 mm d−1. MAE (0.19), NRMSE (0.21) and r2 (0.91) tests indicated that model prediction is significant, and model can be effectively used for the estimation of ET from SEBAL as input of remote sensing data sets. Finally, the SEBAL has been useful for remote agricultural land where ground-based data (Lysimeter data) are not available for daily ET (ET24 h) estimation. The temporal study of the ET24 h values analysed has revealed that the highest ET24 h values are owing to the higher development (high greenness) of crops, whereas the lower values are related to the lower development (low greenness) or null crop. Numéro de notice : A2016-443 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2015.1076062 Date de publication en ligne : 29/09/2015 En ligne : http://dx.doi.org/10.1080/10106049.2015.1076062 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81350
in Geocarto international > vol 31 n° 7 - 8 (July - August 2016) . - pp 739 - 764[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 059-2016041 RAB Revue Centre de documentation En réserve L003 Disponible Assessment of vertical TEC mapping functions for space-based GNSS observations / Jiahao Zhong in GPS solutions, vol 20 n° 3 (July 2016)
PermalinkDirection-of-arrival estimation of VHF signals recorded on the international space station and simultaneous observations of optical lightning / Hiroshi Kikuchi in IEEE Transactions on geoscience and remote sensing, vol 54 n° 7 (July 2016)
PermalinkInteractive discovery of sequential patterns in time series of wind data / Norhakim Yusof in International journal of geographical information science IJGIS, vol 30 n° 7- 8 (July - August 2016)
PermalinkModeling of ionosphere time series using wavelet neural networks (case study: N-W of Iran) / Mir Reza Ghaffari Razin in Advances in space research, vol 58 n° 1 (July 2016)
PermalinkRange imaging of E-region field-aligned irregularities by using a multifrequency technique : validation and initial results / Jenn-Shyong Chen in IEEE Transactions on geoscience and remote sensing, vol 54 n° 7 (July 2016)
PermalinkCharacterization of ionospheric variability in TEC using EOF and wavelets over low-latitude GNSS stations / J.R.K. Kumar Dabbakuti in Advances in space research, vol 57 n° 12 (June 2016)
PermalinkAbove- and belowground tree biomass models for three mangrove species in Tanzania: a nonlinear mixed effects modelling approach / Marco Andrew Njana in Annals of Forest Science, vol 73 n° 2 (June 2016)
PermalinkCork oak pests: a review of insect damage and management / Riziero Tiberi in Annals of Forest Science, vol 73 n° 2 (June 2016)
PermalinkEffects of experimental warming on soil respiration and biomass in Quercus variabilis Blume and Pinus densiflora Sieb. et Zucc. seedlings / Nam Jin Noh in Annals of Forest Science, vol 73 n° 2 (June 2016)
PermalinkEvaluating the productivity of four main tree species in Germany under climate change with static reduced models / Martin Gutsch in Annals of Forest Science, vol 73 n° 2 (June 2016)
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