气候变化领域集成服务门户(CCPortal): The Viscous and Ohmic Damping of the Earth's Free Core Nutation

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DOI	10.1029/2020JB021042
	The Viscous and Ohmic Damping of the Earth's Free Core Nutation
	Triana S.A.; Trinh A.; Rekier J.; Zhu P.; Dehant V.
发表日期	2021
ISSN	21699313
卷号	126 期号:4
英文摘要	The cause for the damping of the Earth's free core nutation (FCN) and the free inner core nutation eigenmodes has been a matter of debate since the earliest reliable estimations from nutation observations were made available. Numerical studies are difficult given the extreme values of some of the parameters associated with the Earth's fluid outer core, where important energy dissipation mechanisms can take place. We present a fully 3D numerical model for the FCN capable of describing accurately viscous and Ohmic dissipation processes taking place in the bulk of the fluid core as well as in the boundary layers. We find an asymptotic regime, appropriate for Earth's parameters, where viscous and Ohmic processes contribute to the total damping, with the dissipation taking place almost exclusively in the boundary layers. By matching the observed nutational damping, we infer an enhanced effective viscosity matching and validating methods from previous studies. We suggest that turbulence caused by the Earth's precession can be a source for the enhanced viscosity. © 2021. The Authors.
英文关键词	core-mantle boundary roughness; inertial modes; nutations; Ohmic dissipation; turbulence
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187198
作者单位	Reference Systems and Planetology, Royal Observatory of Belgium, Brussels, Belgium; Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, United States
推荐引用方式 GB/T 7714	Triana S.A.,Trinh A.,Rekier J.,et al. The Viscous and Ohmic Damping of the Earth's Free Core Nutation[J],2021,126(4).
APA	Triana S.A.,Trinh A.,Rekier J.,Zhu P.,&Dehant V..(2021).The Viscous and Ohmic Damping of the Earth's Free Core Nutation.Journal of Geophysical Research: Solid Earth,126(4).
MLA	Triana S.A.,et al."The Viscous and Ohmic Damping of the Earth's Free Core Nutation".Journal of Geophysical Research: Solid Earth 126.4(2021).