气候变化领域集成服务门户(CCPortal): Committed near-future retreat of Smith, Pope, and Kohler Glaciers inferred by transient model calibration

CCPortal

DOI	10.5194/tcd-9-4459-2015
	Committed near-future retreat of Smith, Pope, and Kohler Glaciers inferred by transient model calibration
	Goldberg D.N.; Heimbach P.; Joughin I.; Smith B.
发表日期	2015
ISSN	19940432
卷号	9 期号:4
英文摘要	A glacial flow model of Smith, Pope and Kohler Glaciers has been calibrated by means of inverse methods against time-varying, annualy resolved observations of ice height and velocities, covering the period 2002 to 2011. The inversion - termed "transient calibration" - produces an optimal set of time-mean, spatially varying parameters together with a time-evolving state that accounts for the transient nature of observations and the model dynamics. Serving as an optimal initial condition, the estimated state for 2011 is used, with no additional forcing, for predicting grounded ice volume loss and grounding line retreat over the ensuing 30 years. The transiently calibrated model predicts a near-steady loss of grounded ice volume of approximately 21 km3 a-1 over this period, as well as loss of 33 km2 a-1 grounded area. We contrast this prediction with one obtained following a commonly used "snapshot" or steady-state inversion, which does not consider time dependence and assumes all observations to be contemporaneous. Transient calibration is shown to achieve a better fit with observations of thinning and grounding line retreat histories, and yields a quantitatively different projection with respect to ice volume loss and ungrounding. Sensitivity studies suggest large near-future levels of unforced, i.e. committed sea level contribution from these ice streams under reasonable assumptions regarding uncertainties of the unknown parameters. © Author(s) 2015.
学科领域	calibration; flow modeling; glacier; glacier retreat; grounding line; ice sheet; inverse analysis; model validation; prediction; steady-state equilibrium; transient flow; uncertainty analysis; Antarctica; Kohler Glacier; Pope Glacier; Smith Glacier; West Antarctica; West Antarctica
语种	英语
scopus关键词	calibration; flow modeling; glacier; glacier retreat; grounding line; ice sheet; inverse analysis; model validation; prediction; steady-state equilibrium; transient flow; uncertainty analysis; Antarctica; Kohler Glacier; Pope Glacier; Smith Glacier; West Antarctica; West Antarctica
来源期刊	Cryosphere Discussions
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/119829
作者单位	University of Edinburgh, School of GeoSciences, Edinburgh, United Kingdom; University of Texas, Institute for Computational Engineering and Sciences/Institute for Geophysics, Austin, TX, United States; Applied Physics Laboratory, University of Washington, Seattle, WA, United States
推荐引用方式 GB/T 7714	Goldberg D.N.,Heimbach P.,Joughin I.,et al. Committed near-future retreat of Smith, Pope, and Kohler Glaciers inferred by transient model calibration[J],2015,9(4).
APA	Goldberg D.N.,Heimbach P.,Joughin I.,&Smith B..(2015).Committed near-future retreat of Smith, Pope, and Kohler Glaciers inferred by transient model calibration.Cryosphere Discussions,9(4).
MLA	Goldberg D.N.,et al."Committed near-future retreat of Smith, Pope, and Kohler Glaciers inferred by transient model calibration".Cryosphere Discussions 9.4(2015).