Cool episodes in the Late Cretaceous - exploring the effects of physical forcing on Antarctic snow accumulation
Until recently it was assumed that the major modern ice sheets on Antarctica became established around the Eocene-Oligocene boundary about 34 Ma ago. But new evidence (e.g. Miller et al., 2008) indicates that continental ice may have been present much earlier, some of it probably even since the gree...
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Copernicus Ges.
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ftoceanrep:oai:oceanrep.geomar.de:8918 2023-05-15T14:11:55+02:00 Cool episodes in the Late Cretaceous - exploring the effects of physical forcing on Antarctic snow accumulation Flögel, Sascha Wallmann, Klaus Kuhnt, Wolfgang 2010 text https://oceanrep.geomar.de/id/eprint/8918/ https://oceanrep.geomar.de/id/eprint/8918/1/Floegel_EGU2010-9334-1.pdf http://meetingorganizer.copernicus.org/EGU2010/EGU2010-9334-1.pdf en eng Copernicus Ges. https://oceanrep.geomar.de/id/eprint/8918/1/Floegel_EGU2010-9334-1.pdf Flögel, S., Wallmann, K. and Kuhnt, W. (2010) Cool episodes in the Late Cretaceous - exploring the effects of physical forcing on Antarctic snow accumulation. [Poster] In: EGU General Assembly. , 02.05.-07.05.2010, Vienna, Austria . Geophysical Research Abstracts. EGU2010-9334 . Conference or Workshop Item NonPeerReviewed 2010 ftoceanrep 2023-04-07T14:57:25Z Until recently it was assumed that the major modern ice sheets on Antarctica became established around the Eocene-Oligocene boundary about 34 Ma ago. But new evidence (e.g. Miller et al., 2008) indicates that continental ice may have been present much earlier, some of it probably even since the greenhouse times of the Late Cretaceous. Deep sea drilling data suggest changes in sea-level during the Late Cretaceous that could have been caused by the melting and freezing of vast ice sheets on Antarctica. Using a GCM approach to test the whether it would be possible to generate the described high-amplitude sealevel falls is one additional way to test this vigorously discussed issue. As shown above, our numerical approach indicates the possibility of a substantial Antarctic glaciation by changing the physical boundary conditions, eccentricity, pCO2, and elevation within reasonable Late Cretaceous ranges. Our simulations suggest that simulated snowfall and consecutive ice formation on Antarctica might yield sufficient volumes to account for the documented rapid, low-amplitude Cretaceous sea-level fluctuations. Based on cautious assumptions and possible errors the model results show that ice build-up could take place in realistic time spans and in accordance with the proxy records. Thus, the possibility of an Antarctic ice shield build-up large enough to drive sea level fluctuations on the order of tens of meters within 20,000-220,000 years is supported. The initial snow accumulation and following growth of Antarctic ice-sheets in the Cretaceous can be attributed to changes in southern hemisphere summer insolation due to reduced orbital eccentricity. Alternatively and/or additionally, declining atmospheric CO2 values caused further cooling Conference Object Antarc* Antarctic Antarctica OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Antarctic |
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Open Polar |
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OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
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ftoceanrep |
language |
English |
description |
Until recently it was assumed that the major modern ice sheets on Antarctica became established around the Eocene-Oligocene boundary about 34 Ma ago. But new evidence (e.g. Miller et al., 2008) indicates that continental ice may have been present much earlier, some of it probably even since the greenhouse times of the Late Cretaceous. Deep sea drilling data suggest changes in sea-level during the Late Cretaceous that could have been caused by the melting and freezing of vast ice sheets on Antarctica. Using a GCM approach to test the whether it would be possible to generate the described high-amplitude sealevel falls is one additional way to test this vigorously discussed issue. As shown above, our numerical approach indicates the possibility of a substantial Antarctic glaciation by changing the physical boundary conditions, eccentricity, pCO2, and elevation within reasonable Late Cretaceous ranges. Our simulations suggest that simulated snowfall and consecutive ice formation on Antarctica might yield sufficient volumes to account for the documented rapid, low-amplitude Cretaceous sea-level fluctuations. Based on cautious assumptions and possible errors the model results show that ice build-up could take place in realistic time spans and in accordance with the proxy records. Thus, the possibility of an Antarctic ice shield build-up large enough to drive sea level fluctuations on the order of tens of meters within 20,000-220,000 years is supported. The initial snow accumulation and following growth of Antarctic ice-sheets in the Cretaceous can be attributed to changes in southern hemisphere summer insolation due to reduced orbital eccentricity. Alternatively and/or additionally, declining atmospheric CO2 values caused further cooling |
format |
Conference Object |
author |
Flögel, Sascha Wallmann, Klaus Kuhnt, Wolfgang |
spellingShingle |
Flögel, Sascha Wallmann, Klaus Kuhnt, Wolfgang Cool episodes in the Late Cretaceous - exploring the effects of physical forcing on Antarctic snow accumulation |
author_facet |
Flögel, Sascha Wallmann, Klaus Kuhnt, Wolfgang |
author_sort |
Flögel, Sascha |
title |
Cool episodes in the Late Cretaceous - exploring the effects of physical forcing on Antarctic snow accumulation |
title_short |
Cool episodes in the Late Cretaceous - exploring the effects of physical forcing on Antarctic snow accumulation |
title_full |
Cool episodes in the Late Cretaceous - exploring the effects of physical forcing on Antarctic snow accumulation |
title_fullStr |
Cool episodes in the Late Cretaceous - exploring the effects of physical forcing on Antarctic snow accumulation |
title_full_unstemmed |
Cool episodes in the Late Cretaceous - exploring the effects of physical forcing on Antarctic snow accumulation |
title_sort |
cool episodes in the late cretaceous - exploring the effects of physical forcing on antarctic snow accumulation |
publisher |
Copernicus Ges. |
publishDate |
2010 |
url |
https://oceanrep.geomar.de/id/eprint/8918/ https://oceanrep.geomar.de/id/eprint/8918/1/Floegel_EGU2010-9334-1.pdf http://meetingorganizer.copernicus.org/EGU2010/EGU2010-9334-1.pdf |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic Antarctica |
genre_facet |
Antarc* Antarctic Antarctica |
op_relation |
https://oceanrep.geomar.de/id/eprint/8918/1/Floegel_EGU2010-9334-1.pdf Flögel, S., Wallmann, K. and Kuhnt, W. (2010) Cool episodes in the Late Cretaceous - exploring the effects of physical forcing on Antarctic snow accumulation. [Poster] In: EGU General Assembly. , 02.05.-07.05.2010, Vienna, Austria . Geophysical Research Abstracts. EGU2010-9334 . |
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