Mechanisms and time scales of glacial inception simulated with an Earth system model of intermediate complexity
We investigate glacial inception and glacial thresholds in the climate-cryosphere system utilising the Earth system model of intermediate complexity CLIMBER-2, which includes modules for atmosphere, terrestrial vegetation, ocean and interactive ice sheets. The latter are described by the three-dimen...
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ftleibnizopen:oai:oai.leibnizopen.de:4eQosIYBdbrxVwz6_1Bg 2023-05-15T16:40:06+02:00 Mechanisms and time scales of glacial inception simulated with an Earth system model of intermediate complexity Calov, R. Ganopolski, A. Kubatzki, C. Claussen, M. 2009 application/pdf https://doi.org/10.34657/1103 https://oa.tib.eu/renate/handle/123456789/625 eng eng München : European Geopyhsical Union CC BY 3.0 Unported https://creativecommons.org/licenses/by/3.0/ CC-BY Climate of the Past, Volume 5, Issue 2, Page 245-258 cryosphere glacier dynamics glaciology ice sheet Northern Hemisphere numerical model orbital forcing 550 article Text 2009 ftleibnizopen https://doi.org/10.34657/1103 2023-03-06T00:32:24Z We investigate glacial inception and glacial thresholds in the climate-cryosphere system utilising the Earth system model of intermediate complexity CLIMBER-2, which includes modules for atmosphere, terrestrial vegetation, ocean and interactive ice sheets. The latter are described by the three-dimensional polythermal ice-sheet model SICOPOLIS. A bifurcation which represents glacial inception is analysed with two different model setups: one setup with dynamical ice-sheet model and another setup without it. The respective glacial thresholds differ in terms of maximum boreal summer insolation at 65° N (hereafter referred as Milankovitch forcing (MF)). The glacial threshold of the configuration without ice-sheet dynamics corresponds to a much lower value of MF compared to the full model. If MF attains values only slightly below the aforementioned threshold there is fast transient response. Depending on the value of MF relative to the glacial threshold, the transient response time of inland-ice volume in the model configuration with ice-sheet dynamics ranges from 10 000 to 100 000 years. Due to these long response times, a glacial threshold obtained in an equilibrium simulation is not directly applicable to the transient response of the climate-cryosphere system to time-dependent orbital forcing. It is demonstrated that in transient simulations just crossing of the glacial threshold does not imply large-scale glaciation of the Northern Hemisphere. We found that in transient simulations MF has to drop well below the glacial threshold determined in an equilibrium simulation to initiate glacial inception. Finally, we show that the asynchronous coupling between climate and inland-ice components allows one sufficient realistic simulation of glacial inception and, at the same time, a considerable reduction of computational costs. publishedVersion Article in Journal/Newspaper Ice Sheet LeibnizOpen (The Leibniz Association) |
institution |
Open Polar |
collection |
LeibnizOpen (The Leibniz Association) |
op_collection_id |
ftleibnizopen |
language |
English |
topic |
cryosphere glacier dynamics glaciology ice sheet Northern Hemisphere numerical model orbital forcing 550 |
spellingShingle |
cryosphere glacier dynamics glaciology ice sheet Northern Hemisphere numerical model orbital forcing 550 Calov, R. Ganopolski, A. Kubatzki, C. Claussen, M. Mechanisms and time scales of glacial inception simulated with an Earth system model of intermediate complexity |
topic_facet |
cryosphere glacier dynamics glaciology ice sheet Northern Hemisphere numerical model orbital forcing 550 |
description |
We investigate glacial inception and glacial thresholds in the climate-cryosphere system utilising the Earth system model of intermediate complexity CLIMBER-2, which includes modules for atmosphere, terrestrial vegetation, ocean and interactive ice sheets. The latter are described by the three-dimensional polythermal ice-sheet model SICOPOLIS. A bifurcation which represents glacial inception is analysed with two different model setups: one setup with dynamical ice-sheet model and another setup without it. The respective glacial thresholds differ in terms of maximum boreal summer insolation at 65° N (hereafter referred as Milankovitch forcing (MF)). The glacial threshold of the configuration without ice-sheet dynamics corresponds to a much lower value of MF compared to the full model. If MF attains values only slightly below the aforementioned threshold there is fast transient response. Depending on the value of MF relative to the glacial threshold, the transient response time of inland-ice volume in the model configuration with ice-sheet dynamics ranges from 10 000 to 100 000 years. Due to these long response times, a glacial threshold obtained in an equilibrium simulation is not directly applicable to the transient response of the climate-cryosphere system to time-dependent orbital forcing. It is demonstrated that in transient simulations just crossing of the glacial threshold does not imply large-scale glaciation of the Northern Hemisphere. We found that in transient simulations MF has to drop well below the glacial threshold determined in an equilibrium simulation to initiate glacial inception. Finally, we show that the asynchronous coupling between climate and inland-ice components allows one sufficient realistic simulation of glacial inception and, at the same time, a considerable reduction of computational costs. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Calov, R. Ganopolski, A. Kubatzki, C. Claussen, M. |
author_facet |
Calov, R. Ganopolski, A. Kubatzki, C. Claussen, M. |
author_sort |
Calov, R. |
title |
Mechanisms and time scales of glacial inception simulated with an Earth system model of intermediate complexity |
title_short |
Mechanisms and time scales of glacial inception simulated with an Earth system model of intermediate complexity |
title_full |
Mechanisms and time scales of glacial inception simulated with an Earth system model of intermediate complexity |
title_fullStr |
Mechanisms and time scales of glacial inception simulated with an Earth system model of intermediate complexity |
title_full_unstemmed |
Mechanisms and time scales of glacial inception simulated with an Earth system model of intermediate complexity |
title_sort |
mechanisms and time scales of glacial inception simulated with an earth system model of intermediate complexity |
publisher |
München : European Geopyhsical Union |
publishDate |
2009 |
url |
https://doi.org/10.34657/1103 https://oa.tib.eu/renate/handle/123456789/625 |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
Climate of the Past, Volume 5, Issue 2, Page 245-258 |
op_rights |
CC BY 3.0 Unported https://creativecommons.org/licenses/by/3.0/ |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.34657/1103 |
_version_ |
1766030479070330880 |