A model for Dansgaard-Oeschger events and millennial-scale abrupt climate change without external forcing
We propose a conceptual model which generates abrupt climate changes akin to Dansgaard-Oeschger events. In the model these abrupt climate changes are not triggered by external perturbations but rather emerge in a dynamic self-consistent model through complex interactions of the ocean, the atmosphere...
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ftdatacite:10.48550/arxiv.2006.00405 2023-05-15T16:00:00+02:00 A model for Dansgaard-Oeschger events and millennial-scale abrupt climate change without external forcing Gottwald, Georg A. 2020 https://dx.doi.org/10.48550/arxiv.2006.00405 https://arxiv.org/abs/2006.00405 unknown arXiv https://dx.doi.org/10.1007/s00382-020-05476-z arXiv.org perpetual, non-exclusive license http://arxiv.org/licenses/nonexclusive-distrib/1.0/ Atmospheric and Oceanic Physics physics.ao-ph Chaotic Dynamics nlin.CD FOS Physical sciences article-journal Article ScholarlyArticle Text 2020 ftdatacite https://doi.org/10.48550/arxiv.2006.00405 https://doi.org/10.1007/s00382-020-05476-z 2022-03-10T15:37:24Z We propose a conceptual model which generates abrupt climate changes akin to Dansgaard-Oeschger events. In the model these abrupt climate changes are not triggered by external perturbations but rather emerge in a dynamic self-consistent model through complex interactions of the ocean, the atmosphere and an intermittent process. The abrupt climate changes are caused in our model by intermittencies in the sea-ice cover. The ocean is represented by a Stommel two-box model, the atmosphere by a Lorenz-84 model and the sea-ice cover by a deterministic approximation of correlated additive and multiplicative noise (CAM) process. The key dynamical ingredients of the model are given by stochastic limits of deterministic multi-scale systems and recent results in deterministic homogenisation theory. The deterministic model reproduces statistical features of actual ice-core data such as non-Gaussian $α$-stable behaviour. The proposed mechanism for abrupt millenial-scale climate change only relies on the existence of a quantity, which exhibits intermittent dynamics on an intermediate time scale. We consider as a particular mechanism intermittent sea-ice cover where the intermittency is generated by emergent atmospheric noise. However, other mechanisms such as freshwater influxes may also be formulated within the proposed framework. Article in Journal/Newspaper Dansgaard-Oeschger events ice core Sea ice DataCite Metadata Store (German National Library of Science and Technology) |
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DataCite Metadata Store (German National Library of Science and Technology) |
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language |
unknown |
topic |
Atmospheric and Oceanic Physics physics.ao-ph Chaotic Dynamics nlin.CD FOS Physical sciences |
spellingShingle |
Atmospheric and Oceanic Physics physics.ao-ph Chaotic Dynamics nlin.CD FOS Physical sciences Gottwald, Georg A. A model for Dansgaard-Oeschger events and millennial-scale abrupt climate change without external forcing |
topic_facet |
Atmospheric and Oceanic Physics physics.ao-ph Chaotic Dynamics nlin.CD FOS Physical sciences |
description |
We propose a conceptual model which generates abrupt climate changes akin to Dansgaard-Oeschger events. In the model these abrupt climate changes are not triggered by external perturbations but rather emerge in a dynamic self-consistent model through complex interactions of the ocean, the atmosphere and an intermittent process. The abrupt climate changes are caused in our model by intermittencies in the sea-ice cover. The ocean is represented by a Stommel two-box model, the atmosphere by a Lorenz-84 model and the sea-ice cover by a deterministic approximation of correlated additive and multiplicative noise (CAM) process. The key dynamical ingredients of the model are given by stochastic limits of deterministic multi-scale systems and recent results in deterministic homogenisation theory. The deterministic model reproduces statistical features of actual ice-core data such as non-Gaussian $α$-stable behaviour. The proposed mechanism for abrupt millenial-scale climate change only relies on the existence of a quantity, which exhibits intermittent dynamics on an intermediate time scale. We consider as a particular mechanism intermittent sea-ice cover where the intermittency is generated by emergent atmospheric noise. However, other mechanisms such as freshwater influxes may also be formulated within the proposed framework. |
format |
Article in Journal/Newspaper |
author |
Gottwald, Georg A. |
author_facet |
Gottwald, Georg A. |
author_sort |
Gottwald, Georg A. |
title |
A model for Dansgaard-Oeschger events and millennial-scale abrupt climate change without external forcing |
title_short |
A model for Dansgaard-Oeschger events and millennial-scale abrupt climate change without external forcing |
title_full |
A model for Dansgaard-Oeschger events and millennial-scale abrupt climate change without external forcing |
title_fullStr |
A model for Dansgaard-Oeschger events and millennial-scale abrupt climate change without external forcing |
title_full_unstemmed |
A model for Dansgaard-Oeschger events and millennial-scale abrupt climate change without external forcing |
title_sort |
model for dansgaard-oeschger events and millennial-scale abrupt climate change without external forcing |
publisher |
arXiv |
publishDate |
2020 |
url |
https://dx.doi.org/10.48550/arxiv.2006.00405 https://arxiv.org/abs/2006.00405 |
genre |
Dansgaard-Oeschger events ice core Sea ice |
genre_facet |
Dansgaard-Oeschger events ice core Sea ice |
op_relation |
https://dx.doi.org/10.1007/s00382-020-05476-z |
op_rights |
arXiv.org perpetual, non-exclusive license http://arxiv.org/licenses/nonexclusive-distrib/1.0/ |
op_doi |
https://doi.org/10.48550/arxiv.2006.00405 https://doi.org/10.1007/s00382-020-05476-z |
_version_ |
1766395872036257792 |