Snow, firn, and ice analysis by digital image processing
[Departement_IRSTEA]EEE [TR1_IRSTEA]23 - ALTEAURISK / DYNAL From satellite remote sensing, global and repetitive measurements of the ice sheets are available. Inversion tools are necessary to get the snow mantle characteristics (snow grain size, density.) from those measurements. For modelling and f...
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ftunivnantes:oai:HAL:tel-02578962v1 2023-05-15T13:32:30+02:00 Snow, firn, and ice analysis by digital image processing Caractérisation de la neige, du névé et de la glace par traitements d'images Gay, M. Érosion torrentielle, neige et avalanches (UR ETGR (ETNA)) Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF) Doctorat spécialité physique méthodes physiques expérimentales, Université Joseph Fourier Grenoble I 1999 https://hal.inrae.fr/tel-02578962 fr fre HAL CCSD tel-02578962 https://hal.inrae.fr/tel-02578962 IRSTEA: PUB00007959 https://hal.inrae.fr/tel-02578962 Sciences de l'environnement. Doctorat spécialité physique méthodes physiques expérimentales, Université Joseph Fourier Grenoble I, 1999. Français. ⟨NNT : ⟩ thesis thèse [SDE]Environmental Sciences info:eu-repo/semantics/doctoralThesis Theses 1999 ftunivnantes 2023-03-08T04:39:18Z [Departement_IRSTEA]EEE [TR1_IRSTEA]23 - ALTEAURISK / DYNAL From satellite remote sensing, global and repetitive measurements of the ice sheets are available. Inversion tools are necessary to get the snow mantle characteristics (snow grain size, density.) from those measurements. For modelling and for comparison with in situ data, size and shape parameters must be clearly defined. Digital image analysis is an adequate tool for providing objective (independent of operator) measurements of the snow characteristics. New methods are developped and applied to a large number of data from Antarctica mainly. Another field of research is the study of the ice core gaz content to get the past atmospheric composition. The snow mantle near rhe surface is porous and therefore there is a difference between the ages of the gaz and of the ice. Snow densification and diffusion models are then used to quantify those processes. The analysis of 2D digital images of Antarctic firn and ice at different depths provided the necessary parameters to validate the models. A third application of digital image analysis was the study of the grain growth in the deep ice. This growth depends on the temperature and the age of the ice. Grain size measurements from thin ice samples are necessary to validate the models. So far those measurements were done manually. New automatic tools were developed which give new insights to this field of study. La télédétection satellitaire est en mesure de fournir des informations globales sur les calottes polaires et d'en effectuer un suivi régulier dans le temps. Pour être facilement interprétées, afin d'en déduire des caractéristiques du manteau neigeux observé depuis l'espace (taille, forme des grains, rugosité de surface.), les données satellitaires doivent être validées et inversées à l'aide de paramétrisations simples. Il est alors indispensable de définir des paramètres robustes et simples de la taille et de la forme des grains de neige à partir de leur observation. Un moyen d'observation et de mesure ... Doctoral or Postdoctoral Thesis Antarc* Antarctic Antarctica ice core Université de Nantes: HAL-UNIV-NANTES Antarctic |
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Open Polar |
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Université de Nantes: HAL-UNIV-NANTES |
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ftunivnantes |
language |
French |
topic |
thesis thèse [SDE]Environmental Sciences |
spellingShingle |
thesis thèse [SDE]Environmental Sciences Gay, M. Snow, firn, and ice analysis by digital image processing |
topic_facet |
thesis thèse [SDE]Environmental Sciences |
description |
[Departement_IRSTEA]EEE [TR1_IRSTEA]23 - ALTEAURISK / DYNAL From satellite remote sensing, global and repetitive measurements of the ice sheets are available. Inversion tools are necessary to get the snow mantle characteristics (snow grain size, density.) from those measurements. For modelling and for comparison with in situ data, size and shape parameters must be clearly defined. Digital image analysis is an adequate tool for providing objective (independent of operator) measurements of the snow characteristics. New methods are developped and applied to a large number of data from Antarctica mainly. Another field of research is the study of the ice core gaz content to get the past atmospheric composition. The snow mantle near rhe surface is porous and therefore there is a difference between the ages of the gaz and of the ice. Snow densification and diffusion models are then used to quantify those processes. The analysis of 2D digital images of Antarctic firn and ice at different depths provided the necessary parameters to validate the models. A third application of digital image analysis was the study of the grain growth in the deep ice. This growth depends on the temperature and the age of the ice. Grain size measurements from thin ice samples are necessary to validate the models. So far those measurements were done manually. New automatic tools were developed which give new insights to this field of study. La télédétection satellitaire est en mesure de fournir des informations globales sur les calottes polaires et d'en effectuer un suivi régulier dans le temps. Pour être facilement interprétées, afin d'en déduire des caractéristiques du manteau neigeux observé depuis l'espace (taille, forme des grains, rugosité de surface.), les données satellitaires doivent être validées et inversées à l'aide de paramétrisations simples. Il est alors indispensable de définir des paramètres robustes et simples de la taille et de la forme des grains de neige à partir de leur observation. Un moyen d'observation et de mesure ... |
author2 |
Érosion torrentielle, neige et avalanches (UR ETGR (ETNA)) Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF) Doctorat spécialité physique méthodes physiques expérimentales, Université Joseph Fourier Grenoble I |
format |
Doctoral or Postdoctoral Thesis |
author |
Gay, M. |
author_facet |
Gay, M. |
author_sort |
Gay, M. |
title |
Snow, firn, and ice analysis by digital image processing |
title_short |
Snow, firn, and ice analysis by digital image processing |
title_full |
Snow, firn, and ice analysis by digital image processing |
title_fullStr |
Snow, firn, and ice analysis by digital image processing |
title_full_unstemmed |
Snow, firn, and ice analysis by digital image processing |
title_sort |
snow, firn, and ice analysis by digital image processing |
publisher |
HAL CCSD |
publishDate |
1999 |
url |
https://hal.inrae.fr/tel-02578962 |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic Antarctica ice core |
genre_facet |
Antarc* Antarctic Antarctica ice core |
op_source |
https://hal.inrae.fr/tel-02578962 Sciences de l'environnement. Doctorat spécialité physique méthodes physiques expérimentales, Université Joseph Fourier Grenoble I, 1999. Français. ⟨NNT : ⟩ |
op_relation |
tel-02578962 https://hal.inrae.fr/tel-02578962 IRSTEA: PUB00007959 |
_version_ |
1766027437025525760 |