DOI: 10.1016/j.palaeo.2013.05.002
论文题名: The amplification of Arctic terrestrial surface temperatures by reduced sea-ice extent during the Pliocene
作者: Ballantyne A.P. ; Axford Y. ; Miller G.H. ; Otto-Bliesner B.L. ; Rosenbloom N. ; White J.W.C.
刊名: Palaeogeography, Palaeoclimatology, Palaeoecology
ISSN: 0031-0182
出版年: 2013
卷: 386 起始页码: 59
结束页码: 67
语种: 英语
英文关键词: Arctic amplification
; Pliocene
; Sea ice
; Terrestrial climate
英文摘要: Many past warm periods exhibited greatly reduced latitudinal temperature gradients as a result of amplified Arctic surface temperatures as well as more seasonably equable temperatures. The Pliocene is a period of particular interest because CO2 forcing was comparable to today and yet Arctic temperatures were significantly warmer than today. Here we describe an atmospheric general circulation model experiment assessing the response of terrestrial temperatures in the mid-Pliocene (3.02 to 3.26Ma) to an ice-free Arctic, and we compare the simulation with a compilation of proxy-based Pliocene paleotemperature reconstructions. Our experiments indicate that the amplification of Arctic surface temperatures is much more sensitive to the extent of sea ice than continental ice. The removal of Arctic sea ice results in simulated mean annual surface temperatures that better match terrestrial proxy data (RMSE=2.9°C) than experimental conditions that included seasonal sea ice (RMSE=4.5°C). Our simulations also show a decrease in the seasonal amplitude of temperatures in the absence of sea-ice, which is consistent with theory predicting more equable climates in the Arctic during warmer intervals in Earth's history. Our results demonstrate that once sea-ice is removed, latent heat is lost from the ocean to the atmosphere as water vapor that can be circulated by the atmosphere, which results in warming of continental interiors. Although our sensitivity experiment does not help to identify the full array of feedback mechanisms responsible for the amplification of Arctic surface temperatures during the Pliocene, it does demonstrate that Arctic terrestrial surface temperatures are extremely sensitive to the spatial and seasonal extent of sea-ice. © 2013 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/69652
Appears in Collections: 过去全球变化的重建
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作者单位: Department of Ecosystem and Conservation Science, University of Montana, Missoula, MT 59812, United States; Department of Earth and Planetary Sciences, Northwestern University, Evanston, IL 60208, United States; Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO 80309, United States; Department of Geological Sciences, University of Colorado, Boulder, CO 80309, United States; Climate and Global Dynamics Division, National Center for Atmospheric Research, Boulder, CO 80305, United States
Recommended Citation:
Ballantyne A.P.,Axford Y.,Miller G.H.,et al. The amplification of Arctic terrestrial surface temperatures by reduced sea-ice extent during the Pliocene[J]. Palaeogeography, Palaeoclimatology, Palaeoecology,2013-01-01,386