Representating high latitudes in a land-surface model : soil freezing and model evaluation
Focus has recently increased on high-latitude climatic processes as awareness rose about the extreme sensitivity of the Arctic to climate change and its potential for major positive climate feedbacks. Modelling offers a powerful tool to assess the climatic impact of changes in the northern high-lati...
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Other Authors: | , , , , , |
Format: | Doctoral or Postdoctoral Thesis |
Language: | French |
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HAL CCSD
2012
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Online Access: | https://theses.hal.science/tel-00845651 https://theses.hal.science/tel-00845651/document https://theses.hal.science/tel-00845651/file/33451_GOUTTEVIN_2012_archivage.pdf |
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ftunigrenoble:oai:HAL:tel-00845651v1 |
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record_format |
openpolar |
institution |
Open Polar |
collection |
Université Grenoble Alpes: HAL |
op_collection_id |
ftunigrenoble |
language |
French |
topic |
5 - 6 - permafrost Climate change Modelling Boreal climate Hydrology Carbone cycle 5 - 6 - pergélisols Changement climatique Modélisation Régions boréales Hydrologie Cycle du carbone [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
5 - 6 - permafrost Climate change Modelling Boreal climate Hydrology Carbone cycle 5 - 6 - pergélisols Changement climatique Modélisation Régions boréales Hydrologie Cycle du carbone [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Gouttevin, Isabelle Representating high latitudes in a land-surface model : soil freezing and model evaluation |
topic_facet |
5 - 6 - permafrost Climate change Modelling Boreal climate Hydrology Carbone cycle 5 - 6 - pergélisols Changement climatique Modélisation Régions boréales Hydrologie Cycle du carbone [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
Focus has recently increased on high-latitude climatic processes as awareness rose about the extreme sensitivity of the Arctic to climate change and its potential for major positive climate feedbacks. Modelling offers a powerful tool to assess the climatic impact of changes in the northern high-latitude regions, as well as to quantify the range of uncertainty stemming from the limits of our knowledge and representation of these environments. My PhD project, dedicated to the improvement of a land-surface model for high-latitude regions and the evaluation of its performances, tackles therefore an issue of concern both for science and society. Soil freezing is a major physical process of boreal regions, with climatic implications. Here, a parameterization of the hydrological effects of soil freezing is developed within the multi-layer hydrological scheme of the land-surface model ORCHIDEE, and its performance is evaluated against observations at different scales, including remotely-sensed data. Taking the hydrological impact of soil freezing into account improves our representation of soil moisture and river discharges over the pan-Arctic land-surface area. However, residual inaccuracies suggest that potential for improvement lies in the representation of temporary surface water reservoirs like floodplains, surface ponding, and, possibly, the introduction of a subgrid variability in soil freezing. Hydrological modelling at high latitudes would also benefit from a specific treatment of mountainous areas and a revision of soil textural input parameters to account for abundant coarse-grained soils in the High-Arctic. Concomitantly, the thermal parameterization of soil freezing in ORCHIDEE is revised and evaluated against field data: latent heat effects yield a reduction but no suppression of a model cold bias in winter soil temperatures, part of which is imputed to the coarse representation of snow in the model. A sensitivity study performed on the insulative properties of taiga vs. tundra snow over the pan-Arctic ... |
author2 |
Laboratoire de glaciologie et géophysique de l'environnement (LGGE) Observatoire des Sciences de l'Univers de Grenoble (OSUG) Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Université de Grenoble Gerhard Krinner Philippe Ciais |
format |
Doctoral or Postdoctoral Thesis |
author |
Gouttevin, Isabelle |
author_facet |
Gouttevin, Isabelle |
author_sort |
Gouttevin, Isabelle |
title |
Representating high latitudes in a land-surface model : soil freezing and model evaluation |
title_short |
Representating high latitudes in a land-surface model : soil freezing and model evaluation |
title_full |
Representating high latitudes in a land-surface model : soil freezing and model evaluation |
title_fullStr |
Representating high latitudes in a land-surface model : soil freezing and model evaluation |
title_full_unstemmed |
Representating high latitudes in a land-surface model : soil freezing and model evaluation |
title_sort |
representating high latitudes in a land-surface model : soil freezing and model evaluation |
publisher |
HAL CCSD |
publishDate |
2012 |
url |
https://theses.hal.science/tel-00845651 https://theses.hal.science/tel-00845651/document https://theses.hal.science/tel-00845651/file/33451_GOUTTEVIN_2012_archivage.pdf |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Climate change permafrost taiga Tundra |
genre_facet |
Arctic Climate change permafrost taiga Tundra |
op_source |
https://theses.hal.science/tel-00845651 Sciences de la Terre. Université de Grenoble, 2012. Français. ⟨NNT : 2012GRENU035⟩ |
op_relation |
NNT: 2012GRENU035 tel-00845651 https://theses.hal.science/tel-00845651 https://theses.hal.science/tel-00845651/document https://theses.hal.science/tel-00845651/file/33451_GOUTTEVIN_2012_archivage.pdf |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1798840476741140480 |
spelling |
ftunigrenoble:oai:HAL:tel-00845651v1 2024-05-12T07:59:20+00:00 Representating high latitudes in a land-surface model : soil freezing and model evaluation Contribution à la représentation des hautes latitudes dans un modèle de surface : gel des sols et diagnostics de performances Gouttevin, Isabelle Laboratoire de glaciologie et géophysique de l'environnement (LGGE) Observatoire des Sciences de l'Univers de Grenoble (OSUG) Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Université de Grenoble Gerhard Krinner Philippe Ciais 2012-12-20 https://theses.hal.science/tel-00845651 https://theses.hal.science/tel-00845651/document https://theses.hal.science/tel-00845651/file/33451_GOUTTEVIN_2012_archivage.pdf fr fre HAL CCSD NNT: 2012GRENU035 tel-00845651 https://theses.hal.science/tel-00845651 https://theses.hal.science/tel-00845651/document https://theses.hal.science/tel-00845651/file/33451_GOUTTEVIN_2012_archivage.pdf info:eu-repo/semantics/OpenAccess https://theses.hal.science/tel-00845651 Sciences de la Terre. Université de Grenoble, 2012. Français. ⟨NNT : 2012GRENU035⟩ 5 - 6 - permafrost Climate change Modelling Boreal climate Hydrology Carbone cycle 5 - 6 - pergélisols Changement climatique Modélisation Régions boréales Hydrologie Cycle du carbone [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/doctoralThesis Theses 2012 ftunigrenoble 2024-04-18T02:14:38Z Focus has recently increased on high-latitude climatic processes as awareness rose about the extreme sensitivity of the Arctic to climate change and its potential for major positive climate feedbacks. Modelling offers a powerful tool to assess the climatic impact of changes in the northern high-latitude regions, as well as to quantify the range of uncertainty stemming from the limits of our knowledge and representation of these environments. My PhD project, dedicated to the improvement of a land-surface model for high-latitude regions and the evaluation of its performances, tackles therefore an issue of concern both for science and society. Soil freezing is a major physical process of boreal regions, with climatic implications. Here, a parameterization of the hydrological effects of soil freezing is developed within the multi-layer hydrological scheme of the land-surface model ORCHIDEE, and its performance is evaluated against observations at different scales, including remotely-sensed data. Taking the hydrological impact of soil freezing into account improves our representation of soil moisture and river discharges over the pan-Arctic land-surface area. However, residual inaccuracies suggest that potential for improvement lies in the representation of temporary surface water reservoirs like floodplains, surface ponding, and, possibly, the introduction of a subgrid variability in soil freezing. Hydrological modelling at high latitudes would also benefit from a specific treatment of mountainous areas and a revision of soil textural input parameters to account for abundant coarse-grained soils in the High-Arctic. Concomitantly, the thermal parameterization of soil freezing in ORCHIDEE is revised and evaluated against field data: latent heat effects yield a reduction but no suppression of a model cold bias in winter soil temperatures, part of which is imputed to the coarse representation of snow in the model. A sensitivity study performed on the insulative properties of taiga vs. tundra snow over the pan-Arctic ... Doctoral or Postdoctoral Thesis Arctic Climate change permafrost taiga Tundra Université Grenoble Alpes: HAL Arctic |