Evolution of Surface Characteristics of Three Debris-Covered Glaciers in the Patagonian Andes From 1958 to 2020
A number of glaciological observations on debris-covered glaciers around the globe have shown a delayed length and mass adjustment in relation to climate variability, a behavior normally attributed to the ice insulation effect of thick debris layers. Dynamic interactions between debris cover, geomet...
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| Format: | Article |
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Frontiers Media S.A.
2021-06-01
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| Series: | Frontiers in Earth Science |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/feart.2021.671854/full |
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| author | Daniel Falaschi Daniel Falaschi Andrés Rivera Andrés Lo Vecchio Repetto Andrés Lo Vecchio Repetto Silvana Moragues Silvana Moragues Ricardo Villalba Philipp Rastner Philipp Rastner Josias Zeller Ana Paula Salcedo |
| author_facet | Daniel Falaschi Daniel Falaschi Andrés Rivera Andrés Lo Vecchio Repetto Andrés Lo Vecchio Repetto Silvana Moragues Silvana Moragues Ricardo Villalba Philipp Rastner Philipp Rastner Josias Zeller Ana Paula Salcedo |
| author_sort | Daniel Falaschi |
| collection | DOAJ |
| description | A number of glaciological observations on debris-covered glaciers around the globe have shown a delayed length and mass adjustment in relation to climate variability, a behavior normally attributed to the ice insulation effect of thick debris layers. Dynamic interactions between debris cover, geometry and surface topography of debris-covered glaciers can nevertheless govern glacier velocities and mass changes over time, with many glaciers exhibiting high thinning rates in spite of thick debris cover. Such interactions are progressively being incorporated into glacier evolution research. In this paper we reconstruct changes in debris-covered area, surface velocities and surface features of three glaciers in the Patagonian Andes over the 1958–2020 period, based on satellite and aerial imagery and Digital Elevation Models. Our results show that debris cover has increased from 40 ± 0.6 to 50 ± 6.7% of the total glacier area since 1958, whilst glacier slope has slightly decreased. The gently sloping tongues have allowed surface flow velocities to remain relatively low (<60 m a−1) for the last two decades, preventing evacuation of surface debris, and contributing to the formation and rise of the ice cliff zone upper boundary. In addition, mapping of end of summer snowline altitudes for the last two decades suggests an increase in the Equilibrium Line Altitudes, which promotes earlier melt out of englacial debris and further increases debris-covered ice area. The strongly negative mass budget of the three investigated glaciers throughout the study period, together with the increases in debris cover extent and ice cliff zones up-glacier, and the low velocities, shows a strong linkage between debris cover, mass balance evolution, surface velocities and topography. Interestingly, the presence of thicker debris layers on the lowermost portions of the glaciers has not lowered thinning rates in these ice areas, indicating that the mass budget is mainly driven by climate variability and calving processes, to which the influence of enhanced thinning at ice cliff location can be added. |
| first_indexed | 2024-12-17T07:02:13Z |
| format | Article |
| id | doaj.art-6d3ab020d193429c9192c0ee9d8f813d |
| institution | Directory Open Access Journal |
| issn | 2296-6463 |
| language | English |
| last_indexed | 2024-12-17T07:02:13Z |
| publishDate | 2021-06-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Earth Science |
| spelling | doaj.art-6d3ab020d193429c9192c0ee9d8f813d2022-12-21T21:59:15ZengFrontiers Media S.A.Frontiers in Earth Science2296-64632021-06-01910.3389/feart.2021.671854671854Evolution of Surface Characteristics of Three Debris-Covered Glaciers in the Patagonian Andes From 1958 to 2020Daniel Falaschi0Daniel Falaschi1Andrés Rivera2Andrés Lo Vecchio Repetto3Andrés Lo Vecchio Repetto4Silvana Moragues5Silvana Moragues6Ricardo Villalba7Philipp Rastner8Philipp Rastner9Josias Zeller10Ana Paula Salcedo11Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales, Mendoza, ArgentinaDepartamento de Geografía, Facultad de Filosofía y Letras, Universidad Nacional de Cuyo, Mendoza, ArgentinaDepartamento de Geografía, Universidad de Chile, Santiago, ChileInstituto Argentino de Nivología, Glaciología y Ciencias Ambientales, Mendoza, ArgentinaDepartamento de Geografía, Facultad de Filosofía y Letras, Universidad Nacional de Cuyo, Mendoza, ArgentinaInstituto Argentino de Nivología, Glaciología y Ciencias Ambientales, Mendoza, ArgentinaDepartamento de Geografía, Facultad de Filosofía y Letras, Universidad Nacional de Cuyo, Mendoza, ArgentinaInstituto Argentino de Nivología, Glaciología y Ciencias Ambientales, Mendoza, ArgentinaGeography Department, University of Zurich, Zürich, SwitzerlandGeoVille Information Systems and Data Processing GmbH, Innsbruck, AustriaGeography Department, University of Zurich, Zürich, SwitzerlandSubgerencia Centro Regional Andino, Instituto Nacional del Agua, Mendoza, ArgentinaA number of glaciological observations on debris-covered glaciers around the globe have shown a delayed length and mass adjustment in relation to climate variability, a behavior normally attributed to the ice insulation effect of thick debris layers. Dynamic interactions between debris cover, geometry and surface topography of debris-covered glaciers can nevertheless govern glacier velocities and mass changes over time, with many glaciers exhibiting high thinning rates in spite of thick debris cover. Such interactions are progressively being incorporated into glacier evolution research. In this paper we reconstruct changes in debris-covered area, surface velocities and surface features of three glaciers in the Patagonian Andes over the 1958–2020 period, based on satellite and aerial imagery and Digital Elevation Models. Our results show that debris cover has increased from 40 ± 0.6 to 50 ± 6.7% of the total glacier area since 1958, whilst glacier slope has slightly decreased. The gently sloping tongues have allowed surface flow velocities to remain relatively low (<60 m a−1) for the last two decades, preventing evacuation of surface debris, and contributing to the formation and rise of the ice cliff zone upper boundary. In addition, mapping of end of summer snowline altitudes for the last two decades suggests an increase in the Equilibrium Line Altitudes, which promotes earlier melt out of englacial debris and further increases debris-covered ice area. The strongly negative mass budget of the three investigated glaciers throughout the study period, together with the increases in debris cover extent and ice cliff zones up-glacier, and the low velocities, shows a strong linkage between debris cover, mass balance evolution, surface velocities and topography. Interestingly, the presence of thicker debris layers on the lowermost portions of the glaciers has not lowered thinning rates in these ice areas, indicating that the mass budget is mainly driven by climate variability and calving processes, to which the influence of enhanced thinning at ice cliff location can be added.https://www.frontiersin.org/articles/10.3389/feart.2021.671854/fulldebris-covered glacierice cliffglacier velocityMonte San LorenzoPatagonian Andes |
| spellingShingle | Daniel Falaschi Daniel Falaschi Andrés Rivera Andrés Lo Vecchio Repetto Andrés Lo Vecchio Repetto Silvana Moragues Silvana Moragues Ricardo Villalba Philipp Rastner Philipp Rastner Josias Zeller Ana Paula Salcedo Evolution of Surface Characteristics of Three Debris-Covered Glaciers in the Patagonian Andes From 1958 to 2020 Frontiers in Earth Science debris-covered glacier ice cliff glacier velocity Monte San Lorenzo Patagonian Andes |
| title | Evolution of Surface Characteristics of Three Debris-Covered Glaciers in the Patagonian Andes From 1958 to 2020 |
| title_full | Evolution of Surface Characteristics of Three Debris-Covered Glaciers in the Patagonian Andes From 1958 to 2020 |
| title_fullStr | Evolution of Surface Characteristics of Three Debris-Covered Glaciers in the Patagonian Andes From 1958 to 2020 |
| title_full_unstemmed | Evolution of Surface Characteristics of Three Debris-Covered Glaciers in the Patagonian Andes From 1958 to 2020 |
| title_short | Evolution of Surface Characteristics of Three Debris-Covered Glaciers in the Patagonian Andes From 1958 to 2020 |
| title_sort | evolution of surface characteristics of three debris covered glaciers in the patagonian andes from 1958 to 2020 |
| topic | debris-covered glacier ice cliff glacier velocity Monte San Lorenzo Patagonian Andes |
| url | https://www.frontiersin.org/articles/10.3389/feart.2021.671854/full |
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