气候变化领域集成服务门户(CCPortal): A Variational Method for Sea Ice Ridging in Earth System Models

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DOI	10.1029/2018MS001395
	A Variational Method for Sea Ice Ridging in Earth System Models
	Roberts A.F.; Hunke E.C.; Kamal S.M.; Lipscomb W.H.; Horvat C.; Maslowski W.
发表日期	2019
ISSN	19422466
起始页码	771
结束页码	805
卷号	11 期号:3
英文摘要	We have derived an analytic form of the thickness redistribution function, Ψ, and compressive strength of sea ice using variational principles. By using the technique of coarse-graining vertical sea ice deformation, or ridging, in the momentum equation of the pack, we isolate frictional energy loss from potential energy gain in the collision of floes. The method accounts for macroporosity of ridge rubble, ϕR, and by including this in the state space of the pack, we expand the sea ice thickness distribution, g(h), to a bivariate distribution, g(h,ϕR). The effect of macroporosity is for the first time included in the large-scale mass conservation and momentum equations of frozen oceans. We make assumptions that have simplified the problem, such as treating sea ice as a granular material in ridges, and assuming that bending moments associated with ridging are perturbations around an isostatic state. Regardless of these simplifications, the coarse-grained ridge model is highly predictive of macroporosity and ridge shape. By ensuring that vertical sea ice deformation observes a variational principle both at the scale of individual ridges and over the pack as a whole, we can predict distributions of ridge shapes using equations that can be solved in Earth system models. Our method also offers the possibility of more accurate derivations of sea ice thickness from ice freeboard measured by space-borne altimeters over polar oceans. ©2019. The Authors.
英文关键词	cryosphere; macroporosity; mechanics; morphology; sea ice; thickness distribution
语种	英语
scopus关键词	Compressive strength; Deformation; Energy dissipation; Mechanics; Morphology; Potential energy; Thickness control; Variational techniques; Bivariate distribution; Cryosphere; Macro-porosity; Redistribution function; Sea ice deformations; Sea ice thickness distributions; Thickness distributions; Variational principles; Sea ice; climate modeling; compressive strength; cryosphere; ice thickness; ice-ocean interaction; numerical method; pack ice; sea ice
来源期刊	Journal of Advances in Modeling Earth Systems
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/156939
作者单位	Department of Oceanography, Naval Postgraduate School, Monterey, CA, United States; Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM, United States; Saildrone Inc., Alameda, CA, United States; Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, United States; Institute at Brown for Environment and Society, Brown University, Providence, RI, United States
推荐引用方式 GB/T 7714	Roberts A.F.,Hunke E.C.,Kamal S.M.,et al. A Variational Method for Sea Ice Ridging in Earth System Models[J],2019,11(3).
APA	Roberts A.F.,Hunke E.C.,Kamal S.M.,Lipscomb W.H.,Horvat C.,&Maslowski W..(2019).A Variational Method for Sea Ice Ridging in Earth System Models.Journal of Advances in Modeling Earth Systems,11(3).
MLA	Roberts A.F.,et al."A Variational Method for Sea Ice Ridging in Earth System Models".Journal of Advances in Modeling Earth Systems 11.3(2019).