气候变化领域集成服务门户(CCPortal): Antarctic sub-shelf melt rates via PICO

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DOI	10.5194/tc-12-1969-2018
	Antarctic sub-shelf melt rates via PICO
	Reese R.; Albrecht T.; Mengel M.; Asay-Davis X.; Winkelmann R.
发表日期	2018
ISSN	19940416
卷号	12 期号:6
英文摘要	Ocean-induced melting below ice shelves is one of the dominant drivers for mass loss from the Antarctic Ice Sheet at present. An appropriate representation of sub-shelf melt rates is therefore essential for model simulations of marine-based ice sheet evolution. Continental-scale ice sheet models often rely on simple melt-parameterizations, in particular for long-term simulations, when fully coupled ice-ocean interaction becomes computationally too expensive. Such parameterizations can account for the influence of the local depth of the ice-shelf draft or its slope on melting. However, they do not capture the effect of ocean circulation underneath the ice shelf. Here we present the Potsdam Ice-shelf Cavity mOdel (PICO), which simulates the vertical overturning circulation in ice-shelf cavities and thus enables the computation of sub-shelf melt rates consistent with this circulation. PICO is based on an ocean box model that coarsely resolves ice shelf cavities and uses a boundary layer melt formulation. We implement it as a module of the Parallel Ice Sheet Model (PISM) and evaluate its performance under present-day conditions of the Southern Ocean. We identify a set of parameters that yield two-dimensional melt rate fields that qualitatively reproduce the typical pattern of comparably high melting near the grounding line and lower melting or refreezing towards the calving front. PICO captures the wide range of melt rates observed for Antarctic ice shelves, with an average of about 0.1m a-1 for cold sub-shelf cavities, for example, underneath Ross or Ronne ice shelves, to 16m a-1 for warm cavities such as in the Amundsen Sea region. This makes PICO a computationally feasible and more physical alternative to melt parameterizations purely based on ice draft geometry. © Author(s) 2018.
学科领域	boundary layer; grounding line; ice sheet; ice shelf; ice-ocean interaction; iceberg calving; oceanic circulation; two-dimensional modeling; Amundsen Sea; Antarctic Ice Sheet; Antarctica; Southern Ocean
语种	英语
scopus关键词	boundary layer; grounding line; ice sheet; ice shelf; ice-ocean interaction; iceberg calving; oceanic circulation; two-dimensional modeling; Amundsen Sea; Antarctic Ice Sheet; Antarctica; Southern Ocean
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/119132
作者单位	Potsdam Institute for Climate Impact Research (PIK), P.O. Box 60 12 03, Potsdam, 14412, Germany; Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, United States; University of Potsdam, Institute of Physics and Astronomy, Karl-Liebknecht-Str. 24-25, Potsdam, 14476, Germany
推荐引用方式 GB/T 7714	Reese R.,Albrecht T.,Mengel M.,et al. Antarctic sub-shelf melt rates via PICO[J],2018,12(6).
APA	Reese R.,Albrecht T.,Mengel M.,Asay-Davis X.,&Winkelmann R..(2018).Antarctic sub-shelf melt rates via PICO.Cryosphere,12(6).
MLA	Reese R.,et al."Antarctic sub-shelf melt rates via PICO".Cryosphere 12.6(2018).