Glacier extent and climate in the Maritime Alps during the Younger Dryas
This study focuses on an Egesen-stadial moraine located at 1906–1920 m asl in the NE Maritime Alps, Europe. Three moraine boulders are dated, via cosmogenic isotope analyses, to 12,490 ± 1120, 12,260 ± 1220 and 13,840 ± 1240 yr, an age compatible with the Younger Dryas cooling event. The reconstruct...
Published in: | Palaeogeography, Palaeoclimatology, Palaeoecology |
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Online Access: | https://hdl.handle.net/11568/1021282 https://doi.org/10.1016/j.palaeo.2019.109400 https://www.sciencedirect.com/science/article/pii/S0031018219305371 |
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ftunivpisairis:oai:arpi.unipi.it:11568/1021282 2024-04-14T08:16:10+00:00 Glacier extent and climate in the Maritime Alps during the Younger Dryas Spagnolo M. Ribolini A. Spagnolo, M. Ribolini, A. 2019 STAMPA https://hdl.handle.net/11568/1021282 https://doi.org/10.1016/j.palaeo.2019.109400 https://www.sciencedirect.com/science/article/pii/S0031018219305371 eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000501656600003 volume:536 numberofpages:11 journal:PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY https://hdl.handle.net/11568/1021282 doi:10.1016/j.palaeo.2019.109400 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85073021042 https://www.sciencedirect.com/science/article/pii/S0031018219305371 info:eu-repo/semantics/openAccess Cosmogenic date Equilibrium Line Altitude Glacier reconstruction Maritime Alp Palaeoclimate Younger Dryas info:eu-repo/semantics/article 2019 ftunivpisairis https://doi.org/10.1016/j.palaeo.2019.109400 2024-03-21T19:04:37Z This study focuses on an Egesen-stadial moraine located at 1906–1920 m asl in the NE Maritime Alps, Europe. Three moraine boulders are dated, via cosmogenic isotope analyses, to 12,490 ± 1120, 12,260 ± 1220 and 13,840 ± 1240 yr, an age compatible with the Younger Dryas cooling event. The reconstructed glacier that deposited the moraine has an equilibrium line altitude of 2349 ± 5 m asl, calculated with an Accumulation Area Balance Ratio of 1.6. The result is very similar to the equilibrium line altitude of another reconstructed glacier that deposited a moraine also dated to Younger Dryas, in the SW Maritime Alps. The similarity suggests comparable climatic conditions across the region during the cooling event. The Younger Dryas palaeoprecipitation is 1549 ± 26 mm/yr, calculated using the empirical law that links precipitation and temperature at a glacier equilibrium line altitude, with palaeotemperatures obtained from nearby palynological and chironomids studies. The palaeoprecipitation is similar to the present, thus indicating non-arid conditions during the Younger Dryas. This is probably due to the Maritime Alps peculiar position, at the crossroads between air masses from the Mediterranean and the North Atlantic, the latter displaced by the southward migration of the polar front. The equilibrium line altitude interval defined by the two reconstructed glaciers, is used to model the extent of another 66 potential Younger Dryas glaciers in the region. Each modelled glacier is reconstructed by iteratively changing the position of its front until the reconstructed glacier has an ELA that falls within the interval. The result, which is checked against geomorphological evidence, shows that glaciers covered 83.74 km2 during the Younger Dryas, with a volume of 5.39 km3. All valley heads were occupied by ice, except for the Maddalena/Larche Pass (1999 m asl), an ideal site for future archaeological, palaeoecological and palaeozoological studies. Article in Journal/Newspaper North Atlantic ARPI - Archivio della Ricerca dell'Università di Pisa Ela ENVELOPE(9.642,9.642,63.170,63.170) Palaeogeography, Palaeoclimatology, Palaeoecology 536 109400 |
institution |
Open Polar |
collection |
ARPI - Archivio della Ricerca dell'Università di Pisa |
op_collection_id |
ftunivpisairis |
language |
English |
topic |
Cosmogenic date Equilibrium Line Altitude Glacier reconstruction Maritime Alp Palaeoclimate Younger Dryas |
spellingShingle |
Cosmogenic date Equilibrium Line Altitude Glacier reconstruction Maritime Alp Palaeoclimate Younger Dryas Spagnolo M. Ribolini A. Glacier extent and climate in the Maritime Alps during the Younger Dryas |
topic_facet |
Cosmogenic date Equilibrium Line Altitude Glacier reconstruction Maritime Alp Palaeoclimate Younger Dryas |
description |
This study focuses on an Egesen-stadial moraine located at 1906–1920 m asl in the NE Maritime Alps, Europe. Three moraine boulders are dated, via cosmogenic isotope analyses, to 12,490 ± 1120, 12,260 ± 1220 and 13,840 ± 1240 yr, an age compatible with the Younger Dryas cooling event. The reconstructed glacier that deposited the moraine has an equilibrium line altitude of 2349 ± 5 m asl, calculated with an Accumulation Area Balance Ratio of 1.6. The result is very similar to the equilibrium line altitude of another reconstructed glacier that deposited a moraine also dated to Younger Dryas, in the SW Maritime Alps. The similarity suggests comparable climatic conditions across the region during the cooling event. The Younger Dryas palaeoprecipitation is 1549 ± 26 mm/yr, calculated using the empirical law that links precipitation and temperature at a glacier equilibrium line altitude, with palaeotemperatures obtained from nearby palynological and chironomids studies. The palaeoprecipitation is similar to the present, thus indicating non-arid conditions during the Younger Dryas. This is probably due to the Maritime Alps peculiar position, at the crossroads between air masses from the Mediterranean and the North Atlantic, the latter displaced by the southward migration of the polar front. The equilibrium line altitude interval defined by the two reconstructed glaciers, is used to model the extent of another 66 potential Younger Dryas glaciers in the region. Each modelled glacier is reconstructed by iteratively changing the position of its front until the reconstructed glacier has an ELA that falls within the interval. The result, which is checked against geomorphological evidence, shows that glaciers covered 83.74 km2 during the Younger Dryas, with a volume of 5.39 km3. All valley heads were occupied by ice, except for the Maddalena/Larche Pass (1999 m asl), an ideal site for future archaeological, palaeoecological and palaeozoological studies. |
author2 |
Spagnolo, M. Ribolini, A. |
format |
Article in Journal/Newspaper |
author |
Spagnolo M. Ribolini A. |
author_facet |
Spagnolo M. Ribolini A. |
author_sort |
Spagnolo M. |
title |
Glacier extent and climate in the Maritime Alps during the Younger Dryas |
title_short |
Glacier extent and climate in the Maritime Alps during the Younger Dryas |
title_full |
Glacier extent and climate in the Maritime Alps during the Younger Dryas |
title_fullStr |
Glacier extent and climate in the Maritime Alps during the Younger Dryas |
title_full_unstemmed |
Glacier extent and climate in the Maritime Alps during the Younger Dryas |
title_sort |
glacier extent and climate in the maritime alps during the younger dryas |
publishDate |
2019 |
url |
https://hdl.handle.net/11568/1021282 https://doi.org/10.1016/j.palaeo.2019.109400 https://www.sciencedirect.com/science/article/pii/S0031018219305371 |
long_lat |
ENVELOPE(9.642,9.642,63.170,63.170) |
geographic |
Ela |
geographic_facet |
Ela |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000501656600003 volume:536 numberofpages:11 journal:PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY https://hdl.handle.net/11568/1021282 doi:10.1016/j.palaeo.2019.109400 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85073021042 https://www.sciencedirect.com/science/article/pii/S0031018219305371 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1016/j.palaeo.2019.109400 |
container_title |
Palaeogeography, Palaeoclimatology, Palaeoecology |
container_volume |
536 |
container_start_page |
109400 |
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1796314757471404032 |