Publication Date:
2020-12-14
Description:
We gratefully acknowledge the support of Italian Ministry of Education, University and Research and Ministry for Environment, Land and Sea through the project GEMINA. Many thanks go to Peter Kohler for providing data and to Narelle van der Wel for her help with English in this paper.
Description:
The present manuscript compares Marine Iso- tope Stage 5 (MIS 5, 125–115 kyr BP) and MIS 7 (236– 229 kyr BP) with the aim to investigate the origin of the difference in ice-sheet growth over the Northern Hemi- sphere high latitudes between these last two inceptions. Our approach combines a low resolution coupled atmosphere– ocean–sea-ice general circulation model and a 3-D thermo- mechanical ice-sheet model to simulate the state of the ice sheets associated with the inception climate states of MIS 5 and MIS 7. Our results show that external forcing (orbitals and GHG) and sea-ice albedo feedbacks are the main fac- tors responsible for the difference in the land-ice initial state between MIS 5 and MIS 7 and that our cold climate model bias impacts more during a cold inception, such as MIS 7, than during a warm inception, such as MIS 5. In addition, if proper ice-elevation and albedo feedbacks are not taken into consideration, the evolution towards glacial inception is hardly simulated, especially for MIS 7. Finally, results high- light that while simulated ice volumes for MIS 5 glacial in- ception almost fit with paleo-reconstructions, the lack of pre- cipitation over high latitudes, identified as a bias of our cli- mate model, does not allow for a proper simulation of MIS 7 glacial inception.
Description:
Italian Ministry of Education, University and Research and Ministry for Environment, Land and Sea through the project GEMINA.
Description:
Published
Description:
269–291
Description:
4A. Clima e Oceani
Description:
JCR Journal
Description:
open
Keywords:
Arctic Oscillation
;
Teleconnections
;
Greenhouse gases
;
Glaciation
;
Paleoclimate
;
Ice Sheet
;
02. Cryosphere::02.03. Ice cores::02.03.05. Paleoclimate
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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