Linear and non-linear response of late Neogene glacial cycles to obliquity forcing and implications for the Milankovitch theory
Constraints are given for the geometry and time lags of the prominent obliquity-paced glacial stages 100, 98 and 96, which mark a major phase in Northern Hemisphere (NH) glaciations during the late Pliocene (2.56–2.4 Ma ago). For this purpose a high-resolution benthic δ18O record was constructed fro...
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ftunivutrecht:oai:dspace.library.uu.nl:1874/197433 2023-07-23T04:19:47+02:00 Linear and non-linear response of late Neogene glacial cycles to obliquity forcing and implications for the Milankovitch theory Lourens, L.J. Becker, J. Bintanja, R. Hilgen, F.J. Tuenter, E. Wal, R.S.W. van de Ziegler, M. 2010 text/plain https://dspace.library.uu.nl/handle/1874/197433 en eng 0277-3791 https://dspace.library.uu.nl/handle/1874/197433 info:eu-repo/semantics/ClosedAccess Aardwetenschappen Natuur- en sterrenkunde obliquity-paced glacial stages glaciations Milankovitch theory glacial cycles climate Article 2010 ftunivutrecht 2023-07-01T23:48:22Z Constraints are given for the geometry and time lags of the prominent obliquity-paced glacial stages 100, 98 and 96, which mark a major phase in Northern Hemisphere (NH) glaciations during the late Pliocene (2.56–2.4 Ma ago). For this purpose a high-resolution benthic δ18O record was constructed from the astronomically tuned Mediterranean ODP Site 967 and decomposed into an ice volume and an annual NH (40–80° N) temperature component using an inverse modelling approach. Our results indicate that the dominant 41 ky component in δ18O lags obliquity by 6.5 ± 0.6 ky, which approximates late Pleistocene estimates. Maximum (minimum) ice volume growth occurred in phase with obliquity minima (maxima), which invoked low (high) total summer energy conditions that reduced (increased) ice-sheet ablation. Sea level dropped 60–70 m during full glacial conditions. Similar to late Pleistocene ice core and marine δ18O records, our late Pliocene δ18O record reveals significant power at 28 ky, which appear to be bound to the major glacial terminations. We argue that this beat most likely reflects the sum frequency of the 41 ky prime and its multiples of 82 and 123 ky, supporting the theory that the late Neogene glacial cycles are primarily determined by the linear and non-linear response mechanisms of the ice sheets to the obliquity forcing. Evidence for such a scenario may come from the alignment between the Devils Hole δ18O chronology and the sum of the filtered linear and non-linear obliquity-related components of late Pleistocene climate records, suggesting that the 28 ky beat is intrinsic to the climate system or at least an important constituent of the annual high-latitude NH temperature changes that have set the stage for the geometry of the glacial–interglacial variability throughout the course of the Pliocene and Pleistocene. Article in Journal/Newspaper ice core Ice Sheet Utrecht University Repository Devils Hole ENVELOPE(0.667,0.667,56.633,56.633) |
institution |
Open Polar |
collection |
Utrecht University Repository |
op_collection_id |
ftunivutrecht |
language |
English |
topic |
Aardwetenschappen Natuur- en sterrenkunde obliquity-paced glacial stages glaciations Milankovitch theory glacial cycles climate |
spellingShingle |
Aardwetenschappen Natuur- en sterrenkunde obliquity-paced glacial stages glaciations Milankovitch theory glacial cycles climate Lourens, L.J. Becker, J. Bintanja, R. Hilgen, F.J. Tuenter, E. Wal, R.S.W. van de Ziegler, M. Linear and non-linear response of late Neogene glacial cycles to obliquity forcing and implications for the Milankovitch theory |
topic_facet |
Aardwetenschappen Natuur- en sterrenkunde obliquity-paced glacial stages glaciations Milankovitch theory glacial cycles climate |
description |
Constraints are given for the geometry and time lags of the prominent obliquity-paced glacial stages 100, 98 and 96, which mark a major phase in Northern Hemisphere (NH) glaciations during the late Pliocene (2.56–2.4 Ma ago). For this purpose a high-resolution benthic δ18O record was constructed from the astronomically tuned Mediterranean ODP Site 967 and decomposed into an ice volume and an annual NH (40–80° N) temperature component using an inverse modelling approach. Our results indicate that the dominant 41 ky component in δ18O lags obliquity by 6.5 ± 0.6 ky, which approximates late Pleistocene estimates. Maximum (minimum) ice volume growth occurred in phase with obliquity minima (maxima), which invoked low (high) total summer energy conditions that reduced (increased) ice-sheet ablation. Sea level dropped 60–70 m during full glacial conditions. Similar to late Pleistocene ice core and marine δ18O records, our late Pliocene δ18O record reveals significant power at 28 ky, which appear to be bound to the major glacial terminations. We argue that this beat most likely reflects the sum frequency of the 41 ky prime and its multiples of 82 and 123 ky, supporting the theory that the late Neogene glacial cycles are primarily determined by the linear and non-linear response mechanisms of the ice sheets to the obliquity forcing. Evidence for such a scenario may come from the alignment between the Devils Hole δ18O chronology and the sum of the filtered linear and non-linear obliquity-related components of late Pleistocene climate records, suggesting that the 28 ky beat is intrinsic to the climate system or at least an important constituent of the annual high-latitude NH temperature changes that have set the stage for the geometry of the glacial–interglacial variability throughout the course of the Pliocene and Pleistocene. |
format |
Article in Journal/Newspaper |
author |
Lourens, L.J. Becker, J. Bintanja, R. Hilgen, F.J. Tuenter, E. Wal, R.S.W. van de Ziegler, M. |
author_facet |
Lourens, L.J. Becker, J. Bintanja, R. Hilgen, F.J. Tuenter, E. Wal, R.S.W. van de Ziegler, M. |
author_sort |
Lourens, L.J. |
title |
Linear and non-linear response of late Neogene glacial cycles to obliquity forcing and implications for the Milankovitch theory |
title_short |
Linear and non-linear response of late Neogene glacial cycles to obliquity forcing and implications for the Milankovitch theory |
title_full |
Linear and non-linear response of late Neogene glacial cycles to obliquity forcing and implications for the Milankovitch theory |
title_fullStr |
Linear and non-linear response of late Neogene glacial cycles to obliquity forcing and implications for the Milankovitch theory |
title_full_unstemmed |
Linear and non-linear response of late Neogene glacial cycles to obliquity forcing and implications for the Milankovitch theory |
title_sort |
linear and non-linear response of late neogene glacial cycles to obliquity forcing and implications for the milankovitch theory |
publishDate |
2010 |
url |
https://dspace.library.uu.nl/handle/1874/197433 |
long_lat |
ENVELOPE(0.667,0.667,56.633,56.633) |
geographic |
Devils Hole |
geographic_facet |
Devils Hole |
genre |
ice core Ice Sheet |
genre_facet |
ice core Ice Sheet |
op_relation |
0277-3791 https://dspace.library.uu.nl/handle/1874/197433 |
op_rights |
info:eu-repo/semantics/ClosedAccess |
_version_ |
1772183195059486720 |