气候变化领域集成服务门户(CCPortal): Influence of temperature fluctuations on equilibrium <br classCombining double low line"break"/>ice sheet volume

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DOI	10.5194/tc-12-39-2018
	Influence of temperature fluctuations on equilibrium ice sheet volume
	Bøgeholm Mikkelsen T.; Grinsted A.; DItlevsen P.
发表日期	2018
ISSN	19940416
卷号	12 期号:1
英文摘要	Forecasting the future sea level relies on accurate modeling of the response of the Greenland and Antarctic ice sheets to changing temperatures. The surface mass balance (SMB) of the Greenland Ice Sheet (GrIS) has a nonlinear response to warming. Cold and warm anomalies of equal size do not cancel out and it is therefore important to consider the effect of interannual fluctuations in temperature.We find that the steady-state volume of an ice sheet is biased toward larger size if interannual temperature fluctuations are not taken into account in numerical modeling of the ice sheet. We illustrate this in a simple ice sheet model and find that the equilibrium ice volume is approximately 1mSLE (meters sea level equivalent) smaller when the simple model is forced with fluctuating temperatures as opposed to a stable climate. It is therefore important to consider the effect of interannual temperature fluctuations when designing long experiments such as paleo-spin-ups. We show how the magnitude of the potential bias can be quantified statistically. For recent simulations of the Greenland Ice Sheet, we estimate the bias to be 30 Gtyr-1 (24-59 Gt yr-1, 95% credibility) for a warming of 3°C above preindustrial values, or 13% (10-25, 95% credibility) of the present-day rate of ice loss. Models of the Greenland Ice Sheet show a collapse threshold beyond which the ice sheet becomes unsustainable. The proximity of the threshold will be underestimated if temperature fluctuations are not taken into account.We estimate the bias to be 0.12°C (0.10-0.18°C, 95% credibility) for a recent estimate of the threshold. In light of our findings it is important to gauge the extent to which this increased variability will influence the mass balance of the ice sheets. © 2018 Author(s).
学科领域	equilibrium; error analysis; ice sheet; mass balance; numerical model; sea level; temperature; temperature effect; threshold; volume; warming; Antarctic Ice Sheet; Antarctica; Arctic; Greenland; Greenland Ice Sheet
语种	英语
scopus关键词	equilibrium; error analysis; ice sheet; mass balance; numerical model; sea level; temperature; temperature effect; threshold; volume; warming; Antarctic Ice Sheet; Antarctica; Arctic; Greenland; Greenland Ice Sheet
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/119245
作者单位	Centre for Ice and Climate, Niels Bohr Institute, Juliane Maries Vej 30, Copenhagen, 2100, Denmark
推荐引用方式 GB/T 7714	Bøgeholm Mikkelsen T.,Grinsted A.,DItlevsen P.. Influence of temperature fluctuations on equilibrium ice sheet volume[J],2018,12(1).
APA	Bøgeholm Mikkelsen T.,Grinsted A.,&DItlevsen P..(2018).Influence of temperature fluctuations on equilibrium ice sheet volume.Cryosphere,12(1).
MLA	Bøgeholm Mikkelsen T.,et al."Influence of temperature fluctuations on equilibrium ice sheet volume".Cryosphere 12.1(2018).