Response of a Large Periglacial River to the current Climate Change
International audience Recent evidence has shown that Arctic regions have warmed about twice as much as elsewhere on the planet over the last decades, and that high-latitude periglacial processes and hydrological systems are deeply impacted by rising temperatures. The study presents recent results c...
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ftinsu:oai:HAL:hal-04525657v1 2024-04-28T08:12:03+00:00 Response of a Large Periglacial River to the current Climate Change Gautier, Emmanuèle Dépret, Thomas Thommeret, Nathalie Costard, François Mousset, Marie Konstantinov, Pavel Fedorov, Alexander Virmoux, Clément Géosciences Paris Saclay (GEOPS) Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) Laboratoire de géographie physique : Environnements Quaternaires et Actuels (LGP) Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS) IAG Coimbra (Portugal), Portugal 2022-09-12 https://hal.science/hal-04525657 https://doi.org/10.5194/icg2022-290 en eng HAL CCSD info:eu-repo/semantics/altIdentifier/doi/10.5194/icg2022-290 hal-04525657 https://hal.science/hal-04525657 doi:10.5194/icg2022-290 10th International Conference on Geomorphology https://hal.science/hal-04525657 10th International Conference on Geomorphology, IAG, Sep 2022, Coimbra (Portugal), Portugal. ⟨10.5194/icg2022-290⟩ [SDE]Environmental Sciences info:eu-repo/semantics/conferenceObject Conference papers 2022 ftinsu https://doi.org/10.5194/icg2022-290 2024-04-05T00:26:21Z International audience Recent evidence has shown that Arctic regions have warmed about twice as much as elsewhere on the planet over the last decades, and that high-latitude periglacial processes and hydrological systems are deeply impacted by rising temperatures. The study presents recent results concerning the fluvial dynamics of a large periglacial river, the Lena River. The Lena river drains a large basin (2.9 million km²) entirely occupied by permafrost (77% with a deep and continuous permafrost). We had previously demonstrated that in the Lena basin, the climate change induces important increase in the river water discharge, that destabilizes the fluvial bed. Here we focus on the fluvial islands dynamics by examining islands with permafrost and islands without permafrost, such comparison being considered as a good indicator of the sensitivity of the hydrosytem to climate change. Island changes are precisely examined: morphological parameters of about 100 islands are surveyed using a GIS on seven series of aerial photographs and satellite images of a 100 km-long reach, for the 1967 – 2017 period. Furthermore, data obtained on several monitored islands allow to analyze the control factors. Field surveys and monitoring of islands shows that within a zone of thick and continuous permafrost, the Lena floodplain is far from being thermally and geomorphologically homogenous: the floodplain rather consists of a juxtaposition of seasonally frozen islands and permanently frozen islands. First, the analysis demonstrates that the two types of islands present different dynamics in terms of erosion and sedimentation. A major change is observed for islands with permafrost at the beginning of the 21 st century: they clearly underwent a stronger erosion for the last twenty years. During the same period, numerous small and non-frozen islands have been formed. Second, the morphological parameters are analyzed with respect to factors that play a major part: water discharge (duration of bar-full, bankfull and flood ... Conference Object Arctic Climate change lena river permafrost Institut national des sciences de l'Univers: HAL-INSU |
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Institut national des sciences de l'Univers: HAL-INSU |
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language |
English |
topic |
[SDE]Environmental Sciences |
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[SDE]Environmental Sciences Gautier, Emmanuèle Dépret, Thomas Thommeret, Nathalie Costard, François Mousset, Marie Konstantinov, Pavel Fedorov, Alexander Virmoux, Clément Response of a Large Periglacial River to the current Climate Change |
topic_facet |
[SDE]Environmental Sciences |
description |
International audience Recent evidence has shown that Arctic regions have warmed about twice as much as elsewhere on the planet over the last decades, and that high-latitude periglacial processes and hydrological systems are deeply impacted by rising temperatures. The study presents recent results concerning the fluvial dynamics of a large periglacial river, the Lena River. The Lena river drains a large basin (2.9 million km²) entirely occupied by permafrost (77% with a deep and continuous permafrost). We had previously demonstrated that in the Lena basin, the climate change induces important increase in the river water discharge, that destabilizes the fluvial bed. Here we focus on the fluvial islands dynamics by examining islands with permafrost and islands without permafrost, such comparison being considered as a good indicator of the sensitivity of the hydrosytem to climate change. Island changes are precisely examined: morphological parameters of about 100 islands are surveyed using a GIS on seven series of aerial photographs and satellite images of a 100 km-long reach, for the 1967 – 2017 period. Furthermore, data obtained on several monitored islands allow to analyze the control factors. Field surveys and monitoring of islands shows that within a zone of thick and continuous permafrost, the Lena floodplain is far from being thermally and geomorphologically homogenous: the floodplain rather consists of a juxtaposition of seasonally frozen islands and permanently frozen islands. First, the analysis demonstrates that the two types of islands present different dynamics in terms of erosion and sedimentation. A major change is observed for islands with permafrost at the beginning of the 21 st century: they clearly underwent a stronger erosion for the last twenty years. During the same period, numerous small and non-frozen islands have been formed. Second, the morphological parameters are analyzed with respect to factors that play a major part: water discharge (duration of bar-full, bankfull and flood ... |
author2 |
Géosciences Paris Saclay (GEOPS) Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) Laboratoire de géographie physique : Environnements Quaternaires et Actuels (LGP) Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS) IAG |
format |
Conference Object |
author |
Gautier, Emmanuèle Dépret, Thomas Thommeret, Nathalie Costard, François Mousset, Marie Konstantinov, Pavel Fedorov, Alexander Virmoux, Clément |
author_facet |
Gautier, Emmanuèle Dépret, Thomas Thommeret, Nathalie Costard, François Mousset, Marie Konstantinov, Pavel Fedorov, Alexander Virmoux, Clément |
author_sort |
Gautier, Emmanuèle |
title |
Response of a Large Periglacial River to the current Climate Change |
title_short |
Response of a Large Periglacial River to the current Climate Change |
title_full |
Response of a Large Periglacial River to the current Climate Change |
title_fullStr |
Response of a Large Periglacial River to the current Climate Change |
title_full_unstemmed |
Response of a Large Periglacial River to the current Climate Change |
title_sort |
response of a large periglacial river to the current climate change |
publisher |
HAL CCSD |
publishDate |
2022 |
url |
https://hal.science/hal-04525657 https://doi.org/10.5194/icg2022-290 |
op_coverage |
Coimbra (Portugal), Portugal |
genre |
Arctic Climate change lena river permafrost |
genre_facet |
Arctic Climate change lena river permafrost |
op_source |
10th International Conference on Geomorphology https://hal.science/hal-04525657 10th International Conference on Geomorphology, IAG, Sep 2022, Coimbra (Portugal), Portugal. ⟨10.5194/icg2022-290⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/icg2022-290 hal-04525657 https://hal.science/hal-04525657 doi:10.5194/icg2022-290 |
op_doi |
https://doi.org/10.5194/icg2022-290 |
_version_ |
1797579130726776832 |