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      Interpretation of Volume and Flux Changes of the Laurichard Rock Glacier Between 1952 and 2019, French Alps

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          Abstract

          Rock glaciers are creeping bodies of ice and rock that account for an important part of the mountain cryosphere. In this study, we investigated long‐term changes of the Laurichard rock glacier (French Alps), to understand how this rock glacier is responding to climate change. Using feature‐tracking and photogrammetric measurements between 1952 and 2019, we quantified changes in thickness, flow velocities and from which we derived the ice/rock flux of the rock glacier at a decadal time scale. This is the first time that emergence velocity and surface mass balance changes have been reconstructed for a rock glacier. Our results reveal a very small surface mass balance ranging from −0.1 m a −1 to +0.05 m a −1, reflecting the role of debris in damping the melt rate of the underlying ice. Surprisingly, we found a more negative surface mass balance in the upper part than in the lower part of the rock glacier during the 1952–1971 cold period, likely due to a reduction in rock and snow mass accumulation. Our study shows that thickness changes are mainly driven by changes in surface mass balance except during the most recent period in the lower part of the rock glacier, which was also influenced by a compressive flow related to a protrusion that prevented the rock glacier from advancing. We conclude that the period 1994–2019 witnessed a marked acceleration in rock glacier flow, in agreement with the observations of other rock glaciers in the European Alps. This strong increase in surface speed is likely a consequence of changes in the basal conditions.

          Key Points

          • We used historical and modern aerial images to document changes in thickness, flow velocities, and the ice/rock flux of the rock glacier

          • This is the first time that emergence velocities and the surface mass balances have been reconstructed for a rock glacier

          • Strong marked acceleration of the entire rock glacier after 1990s, likely a consequence of changes in the basal conditions

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          Most cited references106

          • Record: found
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          • Article: not found

          The Creep of Polycrystalline Ice

          J. W. Glen (1955)
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            • Record: found
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            • Article: not found

            Extracting a climate signal from 169 glacier records.

            I constructed a temperature history for different parts of the world from 169 glacier length records. Using a first-order theory of glacier dynamics, I related changes in glacier length to changes in temperature. The derived temperature histories are fully independent of proxy and instrumental data used in earlier reconstructions. Moderate global warming started in the middle of the 19th century. The reconstructed warming in the first half of the 20th century is 0.5 kelvin. This warming was notably coherent over the globe. The warming signals from glaciers at low and high elevations appear to be very similar.
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              • Record: found
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              • Article: not found

              Co-registration and bias corrections of satellite elevation data sets for quantifying glacier thickness change

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                Author and article information

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                Journal
                Journal of Geophysical Research: Earth Surface
                JGR Earth Surface
                American Geophysical Union (AGU)
                2169-9003
                2169-9011
                September 2021
                September 06 2021
                September 2021
                : 126
                : 9
                Affiliations
                [1 ] Université Grenoble Alpes CNRS IRD Institut de Géosciences de l’Environnement (IGE, UMR 5001) Grenoble France
                [2 ] Laboratoire EDYTEM Université Savoie Mont‐Blanc CNRS Le Bourget du Lac France
                [3 ] Université Grenoble Alpes INRAE UR ETGR Saint‐Martin‐d'Hères France
                Article
                10.1029/2021JF006161
                b0eb7f99-2100-43ac-b06f-ee07d02b97a2
                © 2021

                http://creativecommons.org/licenses/by-nc/4.0/

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