Mass balance and climate history of a high-altitude glacier, Desert Andes of Chile
Glaciers in the dry Chilean Andes provide important ecological services, yet their mass balance response to past and ongoing climate change has been little studied. This study examines the recent (2002-2015), historical (1955-2005), and past (<1900) mass balance history of the high-altitude Guana...
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ftird:oai:ird.fr:fdi:010078966 2024-09-15T18:11:57+00:00 Mass balance and climate history of a high-altitude glacier, Desert Andes of Chile Kinnard, C. /Ginot, Patrick Surazakov, A. MacDonell, S. Nicholson, L. /Patris, Nicolas Rabatel, A. Rivera, A. Squeo, F. A. CHILI ANDES 2020 https://www.documentation.ird.fr/hor/fdi:010078966 EN eng https://www.documentation.ird.fr/hor/fdi:010078966 oai:ird.fr:fdi:010078966 Kinnard C., Ginot Patrick, Surazakov A., MacDonell S., Nicholson L., Patris Nicolas, Rabatel A., Rivera A., Squeo F. A. Mass balance and climate history of a high-altitude glacier, Desert Andes of Chile. 2020, 8, 40 [20 p.] glacier mass balance geodetic mass balance ice core dry Andes climate change stable isotopes sublimation drought text 2020 ftird 2024-08-15T05:57:41Z Glaciers in the dry Chilean Andes provide important ecological services, yet their mass balance response to past and ongoing climate change has been little studied. This study examines the recent (2002-2015), historical (1955-2005), and past (<1900) mass balance history of the high-altitude Guanaco Glacier (29.34 degrees S, >5000 m), using a combination of glaciological, geodetic, and ice core observations. Mass balance has been predominantly negative since 2002. Analysis of mass balance and meteorological data since 2002 suggests that mass balance is currently mostly sensitive to precipitation variations, while low temperatures, aridity and high solar radiation and wind speeds cause large sublimation losses and limited melting. Mass balance reconstructed by geodetic methods shows that Guanaco Glacier has been losing mass since at least 1955, and that mass loss has increased over time until present. An ice core recovered from the deepest part of the glacier in 2008 revealed that the glacier is cold-based with a -5.5 degrees C basal temperature and a warm reversal of the temperature profile above 60-m depth attributed to the recent atmospheric warming trend. Detailed stratigraphic and stable isotope analyses of the upper 20 m of the core revealed seasonal cycles in the delta O-18 and delta H-2 records with periods varying between 0.5 and 3 m. w.e. a(-1). Deuterium excess values larger than 10 parts per thousand suggest limited post-depositional sublimation, while the presence of numerous refrozen ice layers indicate significant summer melt. Tritium concentration in the upper 20 m of the core was very low, while Pb-210 was undetected, indicating that the glacier surface in 2008 was at least 100 years old. Taken together, these results suggest that Guanaco Glacier formed under drastically different climate conditions than today, with humid conditions causing high accumulation rates, reduced sublimation and increased melting. Reconstruction of mass balance based on correlations with precipitation and ... Text ice core IRD (Institute de recherche pour le développement): Horizon |
institution |
Open Polar |
collection |
IRD (Institute de recherche pour le développement): Horizon |
op_collection_id |
ftird |
language |
English |
topic |
glacier mass balance geodetic mass balance ice core dry Andes climate change stable isotopes sublimation drought |
spellingShingle |
glacier mass balance geodetic mass balance ice core dry Andes climate change stable isotopes sublimation drought Kinnard, C. /Ginot, Patrick Surazakov, A. MacDonell, S. Nicholson, L. /Patris, Nicolas Rabatel, A. Rivera, A. Squeo, F. A. Mass balance and climate history of a high-altitude glacier, Desert Andes of Chile |
topic_facet |
glacier mass balance geodetic mass balance ice core dry Andes climate change stable isotopes sublimation drought |
description |
Glaciers in the dry Chilean Andes provide important ecological services, yet their mass balance response to past and ongoing climate change has been little studied. This study examines the recent (2002-2015), historical (1955-2005), and past (<1900) mass balance history of the high-altitude Guanaco Glacier (29.34 degrees S, >5000 m), using a combination of glaciological, geodetic, and ice core observations. Mass balance has been predominantly negative since 2002. Analysis of mass balance and meteorological data since 2002 suggests that mass balance is currently mostly sensitive to precipitation variations, while low temperatures, aridity and high solar radiation and wind speeds cause large sublimation losses and limited melting. Mass balance reconstructed by geodetic methods shows that Guanaco Glacier has been losing mass since at least 1955, and that mass loss has increased over time until present. An ice core recovered from the deepest part of the glacier in 2008 revealed that the glacier is cold-based with a -5.5 degrees C basal temperature and a warm reversal of the temperature profile above 60-m depth attributed to the recent atmospheric warming trend. Detailed stratigraphic and stable isotope analyses of the upper 20 m of the core revealed seasonal cycles in the delta O-18 and delta H-2 records with periods varying between 0.5 and 3 m. w.e. a(-1). Deuterium excess values larger than 10 parts per thousand suggest limited post-depositional sublimation, while the presence of numerous refrozen ice layers indicate significant summer melt. Tritium concentration in the upper 20 m of the core was very low, while Pb-210 was undetected, indicating that the glacier surface in 2008 was at least 100 years old. Taken together, these results suggest that Guanaco Glacier formed under drastically different climate conditions than today, with humid conditions causing high accumulation rates, reduced sublimation and increased melting. Reconstruction of mass balance based on correlations with precipitation and ... |
format |
Text |
author |
Kinnard, C. /Ginot, Patrick Surazakov, A. MacDonell, S. Nicholson, L. /Patris, Nicolas Rabatel, A. Rivera, A. Squeo, F. A. |
author_facet |
Kinnard, C. /Ginot, Patrick Surazakov, A. MacDonell, S. Nicholson, L. /Patris, Nicolas Rabatel, A. Rivera, A. Squeo, F. A. |
author_sort |
Kinnard, C. |
title |
Mass balance and climate history of a high-altitude glacier, Desert Andes of Chile |
title_short |
Mass balance and climate history of a high-altitude glacier, Desert Andes of Chile |
title_full |
Mass balance and climate history of a high-altitude glacier, Desert Andes of Chile |
title_fullStr |
Mass balance and climate history of a high-altitude glacier, Desert Andes of Chile |
title_full_unstemmed |
Mass balance and climate history of a high-altitude glacier, Desert Andes of Chile |
title_sort |
mass balance and climate history of a high-altitude glacier, desert andes of chile |
publishDate |
2020 |
url |
https://www.documentation.ird.fr/hor/fdi:010078966 |
op_coverage |
CHILI ANDES |
genre |
ice core |
genre_facet |
ice core |
op_relation |
https://www.documentation.ird.fr/hor/fdi:010078966 oai:ird.fr:fdi:010078966 Kinnard C., Ginot Patrick, Surazakov A., MacDonell S., Nicholson L., Patris Nicolas, Rabatel A., Rivera A., Squeo F. A. Mass balance and climate history of a high-altitude glacier, Desert Andes of Chile. 2020, 8, 40 [20 p.] |
_version_ |
1810449546236395520 |