DOI: 10.1038/ngeo2119
论文题名: Climate warming during antarctic ice sheet expansion at the middle miocene transition
作者: Knorr G. ; Lohmann G.
刊名: Nature Geoscience
ISSN: 17520894
出版年: 2014
卷: 7, 期: 5 起始页码: 376
结束页码: 381
语种: 英语
Scopus关键词: concentration (composition)
; ice sheet
; Miocene
; oceanic circulation
; sea ice
; surface water
; Southern Ocean
英文摘要: During the Middle Miocene climate transition about 14 million years ago, the Antarctic ice sheet expanded to near-modern volume. Surprisingly, this ice sheet growth was accompanied by a warming in the surface waters of the Southern Ocean, whereas a slight deep-water temperature increase was delayed by more than 200 thousand years. Here we use a coupled atmosphere-ocean model to assess the relative effects of changes in atmospheric CO2 concentration and ice sheet growth on regional and global temperatures. In the simulations, changes in the wind field associated with the growth of the ice sheet induce changes in ocean circulation, deep-water formation and sea-ice cover that result in sea surface warming and deep-water cooling in large swaths of the Atlantic and Indian ocean sectors of the Southern Ocean. We interpret these changes as the dominant ocean surface response to a 100-thousand-year phase of massive ice growth in Antarctica. A rise in global annual mean temperatures is also seen in response to increased Antarctic ice surface elevation. In contrast, the longer-term surface and deep-water temperature trends are dominated by changes in atmospheric CO2 concentration. We therefore conclude that the climatic and oceanographic impacts of the Miocene expansion of the Antarctic ice sheet are governed by a complex interplay between wind field, ocean circulation and the sea-ice system. © 2014 Macmillan Publishers Limited. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/106479
Appears in Collections: 气候减缓与适应 科学计划与规划
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作者单位: Alfred Wegener Institute, Helmholtz-Center for Polar and Marine Research, Bussestraße 24, D-27570 Bremerhaven, Germany; School of Earth and Ocean Sciences, Cardiff University, Cardiff, CF10 3AT, United Kingdom; MARUM-Center for Marine Environmental Sciences, University Bremen, Leobener Straße, D-28359 Bremen, Germany
Recommended Citation:
Knorr G.,Lohmann G.. Climate warming during antarctic ice sheet expansion at the middle miocene transition[J]. Nature Geoscience,2014-01-01,7(5)