| DOI: | 10.5194/cp-8-1011-2012
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| Scopus记录号: | 2-s2.0-84880983707
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| 论文题名: | Role of CO2 and Southern Ocean winds in glacial abrupt climate change |
| 作者: | Banderas R.; Álvarez-Solas J.; Montoya M.
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| 刊名: | Climate of the Past
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| ISSN: | 18149324
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| 出版年: | 2012
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| 卷: | 8, 期:3 | | 起始页码: | 1011
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| 结束页码: | 1021
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| 语种: | 英语
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| Scopus关键词: | air temperature
; carbon dioxide
; climate change
; Dansgaard-Oeschger cycle
; freshwater input
; GRIP
; North Atlantic Deep Water
; overturn
; proxy climate record
; sea ice
; westerly
; Arctic
; Arctic Ocean
; Atlantic Ocean
; Atlantic Ocean (North)
; Greenland
; Norwegian Sea
; Southern Ocean
|
| 英文摘要: | The study of Greenland ice cores revealed two decades ago the abrupt character of glacial millennial-scale climate variability. Several triggering mechanisms have been proposed and confronted against growing proxy-data evidence. Although the implication of North Atlantic deep water (NADW) formation reorganisations in glacial abrupt climate change seems robust nowadays, the final cause of these reorganisations remains unclear. Here, the role of CO2 and Southern Ocean winds is investigated using a coupled model of intermediate complexity in an experimental setup designed such that the climate system resides close to a threshold found in previous studies. An initial abrupt surface air temperature (SAT) increase over the North Atlantic by 4 K in less than a decade, followed by a more gradual warming greater than 10 K on centennial timescales, is simulated in response to increasing atmospheric CO2 levels and/or enhancing southern westerlies. The simulated peak warming shows a similar pattern and amplitude over Greenland as registered in ice core records of Dansgaard-Oeschger (D/O) events. This is accompanied by a strong Atlantic meridional overturning circulation (AMOC) intensification. The AMOC strengthening is found to be caused by a northward shift of NADW formation sites into the Nordic Seas as a result of a northward retreat of the sea-ice front in response to higher temperatures. This leads to enhanced heat loss to the atmosphere as well as reduced freshwater fluxes via reduced sea-ice import into the region. In this way, a new mechanism that is consistent with proxy data is identified by which abrupt climate change can be promoted.© Author(s) 2012. |
| Citation statistics: |
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| 资源类型: | 期刊论文
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| 标识符: | http://119.78.100.158/handle/2HF3EXSE/49519
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| Appears in Collections: | 气候变化与战略
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| Recommended Citation: | |
Banderas R.,Álvarez-Solas J.,Montoya M.. Role of CO2 and Southern Ocean winds in glacial abrupt climate change[J]. Climate of the Past,2012-01-01,8(3)
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