Cryogenic cave carbonates in the Dolomites (northern Italy): insights into Younger Dryas cooling and seasonal precipitation
<p>In the European Alps, the Younger Dryas (YD) was characterised by the last major glacier advance, with equilibrium line altitudes being <span class="inline-formula">∼</span> 220 to 290 m lower than during the Little Ice Age, and also by the development of rock glaciers...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2021-04-01
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| Series: | Climate of the Past |
| Online Access: | https://cp.copernicus.org/articles/17/775/2021/cp-17-775-2021.pdf |
| _version_ | 1818718029096157184 |
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| author | G. Koltai C. Spötl A. H. Jarosch H. Cheng H. Cheng H. Cheng |
| author_facet | G. Koltai C. Spötl A. H. Jarosch H. Cheng H. Cheng H. Cheng |
| author_sort | G. Koltai |
| collection | DOAJ |
| description | <p>In the European Alps, the Younger Dryas (YD) was
characterised by the last major glacier advance, with equilibrium line
altitudes being <span class="inline-formula">∼</span> 220 to 290 m lower than during the Little
Ice Age, and also by the development of rock glaciers. Dating of these
geomorphic features, however, is associated with substantial uncertainties,
leading to considerable ambiguities regarding the internal structure of this
stadial, which is the most intensively studied one of the last glacial period. Here,
we provide robust physical evidence based on <span class="inline-formula"><sup>230</sup></span>Th-dated cryogenic cave
carbonates (CCCs) from a cave located at 2274 m a.s.l. in the Dolomites of
northern Italy coupled with thermal modelling, indicating that early YD
winters were only moderately cold in this part of the Alps. More precisely,
we find that the mean annual air temperature dropped <span class="inline-formula">≤</span> 3 <span class="inline-formula"><sup>∘</sup></span>C
at the Allerød–YD transition. Our data suggest that autumns and early
winters in the early part of the YD were relatively snow-rich, resulting in
stable winter snow cover. The latter insulated the shallow subsurface in
winter and allowed the cave interior to remain close to the freezing point
(0 <span class="inline-formula"><sup>∘</sup></span>C) year-round, promoting CCC formation. The main phase of CCC
precipitation at <span class="inline-formula">∼</span> 12.2 ka coincided with the mid-YD
transition recorded in other archives across Europe. Based on thermal
modelling we propose that CCC formation at <span class="inline-formula">∼</span> 12.2 ka was
most likely associated with a slight warming of approximately
<span class="inline-formula">+</span>1 <span class="inline-formula"><sup>∘</sup></span>C in conjunction with drier autumns and early winters in the
second half of the YD. These changes triggered CCC formation in this Alpine
cave as well as ice glacier retreat and rock glacier expansion across the
Alps.</p> |
| first_indexed | 2024-12-17T19:44:33Z |
| format | Article |
| id | doaj.art-5e88f090bf794565990f90fe96b7b702 |
| institution | Directory Open Access Journal |
| issn | 1814-9324 1814-9332 |
| language | English |
| last_indexed | 2024-12-17T19:44:33Z |
| publishDate | 2021-04-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Climate of the Past |
| spelling | doaj.art-5e88f090bf794565990f90fe96b7b7022022-12-21T21:34:54ZengCopernicus PublicationsClimate of the Past1814-93241814-93322021-04-011777578910.5194/cp-17-775-2021Cryogenic cave carbonates in the Dolomites (northern Italy): insights into Younger Dryas cooling and seasonal precipitationG. Koltai0C. Spötl1A. H. Jarosch2H. Cheng3H. Cheng4H. Cheng5Institute of Geology, University of Innsbruck, Innrain 52d, 6020 Innsbruck, AustriaInstitute of Geology, University of Innsbruck, Innrain 52d, 6020 Innsbruck, AustriaThetaFrame Solutions, Hörfarterstrasse 14, 6330 Kufstein, AustriaInstitute of Global Environmental Change, Xi'an Jiaotong University, Xi'an, ChinaState Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, ChinaDepartment of Earth Sciences, University of Minnesota, Minneapolis, MN, USA<p>In the European Alps, the Younger Dryas (YD) was characterised by the last major glacier advance, with equilibrium line altitudes being <span class="inline-formula">∼</span> 220 to 290 m lower than during the Little Ice Age, and also by the development of rock glaciers. Dating of these geomorphic features, however, is associated with substantial uncertainties, leading to considerable ambiguities regarding the internal structure of this stadial, which is the most intensively studied one of the last glacial period. Here, we provide robust physical evidence based on <span class="inline-formula"><sup>230</sup></span>Th-dated cryogenic cave carbonates (CCCs) from a cave located at 2274 m a.s.l. in the Dolomites of northern Italy coupled with thermal modelling, indicating that early YD winters were only moderately cold in this part of the Alps. More precisely, we find that the mean annual air temperature dropped <span class="inline-formula">≤</span> 3 <span class="inline-formula"><sup>∘</sup></span>C at the Allerød–YD transition. Our data suggest that autumns and early winters in the early part of the YD were relatively snow-rich, resulting in stable winter snow cover. The latter insulated the shallow subsurface in winter and allowed the cave interior to remain close to the freezing point (0 <span class="inline-formula"><sup>∘</sup></span>C) year-round, promoting CCC formation. The main phase of CCC precipitation at <span class="inline-formula">∼</span> 12.2 ka coincided with the mid-YD transition recorded in other archives across Europe. Based on thermal modelling we propose that CCC formation at <span class="inline-formula">∼</span> 12.2 ka was most likely associated with a slight warming of approximately <span class="inline-formula">+</span>1 <span class="inline-formula"><sup>∘</sup></span>C in conjunction with drier autumns and early winters in the second half of the YD. These changes triggered CCC formation in this Alpine cave as well as ice glacier retreat and rock glacier expansion across the Alps.</p>https://cp.copernicus.org/articles/17/775/2021/cp-17-775-2021.pdf |
| spellingShingle | G. Koltai C. Spötl A. H. Jarosch H. Cheng H. Cheng H. Cheng Cryogenic cave carbonates in the Dolomites (northern Italy): insights into Younger Dryas cooling and seasonal precipitation Climate of the Past |
| title | Cryogenic cave carbonates in the Dolomites (northern Italy): insights into Younger Dryas cooling and seasonal precipitation |
| title_full | Cryogenic cave carbonates in the Dolomites (northern Italy): insights into Younger Dryas cooling and seasonal precipitation |
| title_fullStr | Cryogenic cave carbonates in the Dolomites (northern Italy): insights into Younger Dryas cooling and seasonal precipitation |
| title_full_unstemmed | Cryogenic cave carbonates in the Dolomites (northern Italy): insights into Younger Dryas cooling and seasonal precipitation |
| title_short | Cryogenic cave carbonates in the Dolomites (northern Italy): insights into Younger Dryas cooling and seasonal precipitation |
| title_sort | cryogenic cave carbonates in the dolomites northern italy insights into younger dryas cooling and seasonal precipitation |
| url | https://cp.copernicus.org/articles/17/775/2021/cp-17-775-2021.pdf |
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