气候变化领域集成服务门户(CCPortal): Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM)-Part 2: Parameter ensemble analysis

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DOI	10.5194/tc-14-633-2020
	Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM)-Part 2: Parameter ensemble analysis
	Albrecht T.; Winkelmann R.; Levermann A.
发表日期	2020
ISSN	19940416
起始页码	633
结束页码	656
卷号	14 期号:2
英文摘要	The Parallel Ice Sheet Model (PISM) is applied to the Antarctic Ice Sheet over the last two glacial cycles ( ≈ 210 000 years) with a resolution of 16 km. An ensemble of 256 model runs is analyzed in which four relevant model parameters have been systematically varied using fullfactorial parameter sampling. Parameters and plausible parameter ranges have been identified in a companion paper (Albrecht et al., 2020) and are associated with ice dynamics, climatic forcing, basal sliding and bed deformation and represent distinct classes of model uncertainties. The model is scored against both modern and geologic data, including reconstructed grounding-line locations, elevation-age data, ice thickness, surface velocities and uplift rates. An aggregated score is computed for each ensemble member that measures the overall model-data misfit, including measurement uncertainty in terms of a Gaussian error model (Briggs and Tarasov, 2013). The statistical method used to analyze the ensemble simulation results follows closely the simple averaging method described in Pollard et al. (2016). This analysis reveals clusters of best-fit parameter combinations, and hence a likely range of relevant model and boundary parameters, rather than individual best-fit parameters. The ensemble of reconstructed histories of Antarctic Ice Sheet volumes provides a score-weighted likely range of sealevel contributions since the Last Glacial Maximum (LGM) of 9:4±4:1m (or 6:5±2:0×106 km3), which is at the upper range of most previous studies. The last deglaciation occurs in all ensemble simulations after around 12 000 years before present and hence after the meltwater pulse 1A (MWP1a). Our ensemble analysis also provides an estimate of parametric uncertainty bounds for the present-day state that can be used for PISM projections of future sea-level contributions from the Antarctic Ice Sheet. © Author(s) 2020.
英文关键词	glacial-interglacial cycle; last deglaciation; Last Glacial Maximum; meltwater; parameter estimation; sea level change; simulation; Antarctic Ice Sheet; Antarctica
语种	英语
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202010
作者单位	Potsdam Institute for Climate Impact Research (PIK), Member of the Leibniz Association, P.O. Box 601203, Potsdam, 14412, Germany; University of Potsdam, Institute of Physics and Astronomy, Karl-Liebknecht-Str. 24-25, Potsdam, 14476, Germany; Lamont-Doherty Earth Observatory, Columbia University, New York, United States
推荐引用方式 GB/T 7714	Albrecht T.,Winkelmann R.,Levermann A.. Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM)-Part 2: Parameter ensemble analysis[J],2020,14(2).
APA	Albrecht T.,Winkelmann R.,&Levermann A..(2020).Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM)-Part 2: Parameter ensemble analysis.Cryosphere,14(2).
MLA	Albrecht T.,et al."Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM)-Part 2: Parameter ensemble analysis".Cryosphere 14.2(2020).