DOI: 10.5194/tc-14-599-2020
论文题名: Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM)-Part 1: Boundary conditions and climatic forcing
作者: Albrecht T. ; Winkelmann R. ; Levermann A.
刊名: Cryosphere
ISSN: 19940416
出版年: 2020
卷: 14, 期: 2 语种: 英语
Scopus关键词: boundary condition
; climate forcing
; heat flux
; ice sheet
; ice-ocean interaction
; iceberg calving
; Last Glacial
; sea level change
; sea surface temperature
; Antarctic Ice Sheet
; Antarctica
英文摘要: Simulations of the glacial-interglacial history of the Antarctic Ice Sheet provide insights into dynamic threshold behavior and estimates of the ice sheet's contributions to global sea-level changes for the past, present and future. However, boundary conditions are weakly constrained, in particular at the interface of the ice sheet and the bedrock. Also climatic forcing covering the last glacial cycles is uncertain, as it is based on sparse proxy data. We use the Parallel Ice Sheet Model (PISM) to investigate the dynamic effects of different choices of input data, e.g., for modern basal heat flux or reconstructions of past changes of sea level and surface temperature. As computational resources are limited, glacial-cycle simulations are performed using a comparably coarse model grid of 16 km and various parameterizations, e.g., for basal sliding, iceberg calving, or for past variations in precipitation and ocean temperatures. In this study we evaluate the model's transient sensitivity to corresponding parameter choices and to different boundary conditions over the last two glacial cycles and provide estimates of involved uncertainties.We also discuss isolated and combined effects of climate and sea-level forcing. Hence, this study serves as a "cookbook" for the growing community of PISM users and paleo-ice sheet modelers in general. For each of the different model uncertainties with regard to climatic forcing, ice and Earth dynamics, and basal processes, we select one representative model parameter that captures relevant uncertainties and motivates corresponding parameter ranges that bound the observed ice volume at present. The four selected parameters are systematically varied in a parameter ensemble analysis, which is described in a companion paper. © Author(s) 2020. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/159299
Appears in Collections: 气候变化与战略
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作者单位: Potsdam Institute for Climate Impact Research (PIK), Member of the Leibniz Association, P.O. Box 601203, Potsdam, 14412, Germany; Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, Potsdam, 14476, Germany; Lamont-Doherty Earth Observatory, Columbia University, New York, United States
Recommended Citation:
Albrecht T.,Winkelmann R.,Levermann A.. Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM)-Part 1: Boundary conditions and climatic forcing[J]. Cryosphere,2020-01-01,14(2)