A simple conceptual model of abrupt glacial climate events
International audience Here we use a very simple conceptual model in an attempt to reduce essential parts of the complex nonlinearity of abrupt glacial climate changes (the so-called Dansgaard-Oeschger events) to a few simple principles, namely (i) the existence of two different climate states, (ii)...
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ftinsu:oai:HAL:hal-00302932v1 2023-11-12T04:16:21+01:00 A simple conceptual model of abrupt glacial climate events Braun, H. Ganopolski, A. Christl, M. Chialvo, D. R. Heidelberg Academy of Sciences and Humanities Potsdam Institute for Climate Impact Research (PIK) PSI/ETH Laboratory for Ion Beam Physics c/o Institute of Particle Physics Department of Physiology Feinberg Medical School 2007-11-23 https://hal.science/hal-00302932 https://hal.science/hal-00302932/document https://hal.science/hal-00302932/file/npg-14-709-2007.pdf en eng HAL CCSD European Geosciences Union (EGU) hal-00302932 https://hal.science/hal-00302932 https://hal.science/hal-00302932/document https://hal.science/hal-00302932/file/npg-14-709-2007.pdf info:eu-repo/semantics/OpenAccess ISSN: 1023-5809 EISSN: 1607-7946 Nonlinear Processes in Geophysics https://hal.science/hal-00302932 Nonlinear Processes in Geophysics, 2007, 14 (6), pp.709-721 [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO] [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2007 ftinsu 2023-10-25T16:26:26Z International audience Here we use a very simple conceptual model in an attempt to reduce essential parts of the complex nonlinearity of abrupt glacial climate changes (the so-called Dansgaard-Oeschger events) to a few simple principles, namely (i) the existence of two different climate states, (ii) a threshold process and (iii) an overshooting in the stability of the system at the start and the end of the events, which is followed by a millennial-scale relaxation. By comparison with a so-called Earth system model of intermediate complexity (CLIMBER-2), in which the events represent oscillations between two climate states corresponding to two fundamentally different modes of deep-water formation in the North Atlantic, we demonstrate that the conceptual model captures fundamental aspects of the nonlinearity of the events in that model. We use the conceptual model in order to reproduce and reanalyse nonlinear resonance mechanisms that were already suggested in order to explain the characteristic time scale of Dansgaard-Oeschger events. In doing so we identify a new form of stochastic resonance (i.e. an overshooting stochastic resonance ) and provide the first explicitly reported manifestation of ghost resonance in a geosystem, i.e. of a mechanism which could be relevant for other systems with thresholds and with multiple states of operation. Our work enables us to explicitly simulate realistic probability measures of Dansgaard-Oeschger events (e.g. waiting time distributions, which are a prerequisite for statistical analyses on the regularity of the events by means of Monte-Carlo simulations). We thus think that our study is an important advance in order to develop more adequate methods to test the statistical significance and the origin of the proposed glacial 1470-year climate cycle. Article in Journal/Newspaper Dansgaard-Oeschger events North Atlantic Institut national des sciences de l'Univers: HAL-INSU |
institution |
Open Polar |
collection |
Institut national des sciences de l'Univers: HAL-INSU |
op_collection_id |
ftinsu |
language |
English |
topic |
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO] [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO] [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Braun, H. Ganopolski, A. Christl, M. Chialvo, D. R. A simple conceptual model of abrupt glacial climate events |
topic_facet |
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO] [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience Here we use a very simple conceptual model in an attempt to reduce essential parts of the complex nonlinearity of abrupt glacial climate changes (the so-called Dansgaard-Oeschger events) to a few simple principles, namely (i) the existence of two different climate states, (ii) a threshold process and (iii) an overshooting in the stability of the system at the start and the end of the events, which is followed by a millennial-scale relaxation. By comparison with a so-called Earth system model of intermediate complexity (CLIMBER-2), in which the events represent oscillations between two climate states corresponding to two fundamentally different modes of deep-water formation in the North Atlantic, we demonstrate that the conceptual model captures fundamental aspects of the nonlinearity of the events in that model. We use the conceptual model in order to reproduce and reanalyse nonlinear resonance mechanisms that were already suggested in order to explain the characteristic time scale of Dansgaard-Oeschger events. In doing so we identify a new form of stochastic resonance (i.e. an overshooting stochastic resonance ) and provide the first explicitly reported manifestation of ghost resonance in a geosystem, i.e. of a mechanism which could be relevant for other systems with thresholds and with multiple states of operation. Our work enables us to explicitly simulate realistic probability measures of Dansgaard-Oeschger events (e.g. waiting time distributions, which are a prerequisite for statistical analyses on the regularity of the events by means of Monte-Carlo simulations). We thus think that our study is an important advance in order to develop more adequate methods to test the statistical significance and the origin of the proposed glacial 1470-year climate cycle. |
author2 |
Heidelberg Academy of Sciences and Humanities Potsdam Institute for Climate Impact Research (PIK) PSI/ETH Laboratory for Ion Beam Physics c/o Institute of Particle Physics Department of Physiology Feinberg Medical School |
format |
Article in Journal/Newspaper |
author |
Braun, H. Ganopolski, A. Christl, M. Chialvo, D. R. |
author_facet |
Braun, H. Ganopolski, A. Christl, M. Chialvo, D. R. |
author_sort |
Braun, H. |
title |
A simple conceptual model of abrupt glacial climate events |
title_short |
A simple conceptual model of abrupt glacial climate events |
title_full |
A simple conceptual model of abrupt glacial climate events |
title_fullStr |
A simple conceptual model of abrupt glacial climate events |
title_full_unstemmed |
A simple conceptual model of abrupt glacial climate events |
title_sort |
simple conceptual model of abrupt glacial climate events |
publisher |
HAL CCSD |
publishDate |
2007 |
url |
https://hal.science/hal-00302932 https://hal.science/hal-00302932/document https://hal.science/hal-00302932/file/npg-14-709-2007.pdf |
genre |
Dansgaard-Oeschger events North Atlantic |
genre_facet |
Dansgaard-Oeschger events North Atlantic |
op_source |
ISSN: 1023-5809 EISSN: 1607-7946 Nonlinear Processes in Geophysics https://hal.science/hal-00302932 Nonlinear Processes in Geophysics, 2007, 14 (6), pp.709-721 |
op_relation |
hal-00302932 https://hal.science/hal-00302932 https://hal.science/hal-00302932/document https://hal.science/hal-00302932/file/npg-14-709-2007.pdf |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1782333467085766656 |