气候变化领域集成服务门户(CCPortal): Longitudinal structure of Earth's magnetic field controlled by lower mantle heat flow

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DOI	10.1038/s41561-023-01148-9
	Longitudinal structure of Earth's magnetic field controlled by lower mantle heat flow
	Mound, Jonathan E. E.; Davies, Christopher J. J.
发表日期	2022
ISSN	1752-0894
EISSN	1752-0908
页码	15
英文摘要	Thermal interactions between Earth's core and mantle provide the power that maintains the geomagnetic field. However, the effect of these interactions and, in particular, the thermochemical piles at the base of the mantle on magnetic field behaviour remains uncertain. Here we present numerical dynamo simulations with strong lateral variations in heat flow imposed at the core-mantle boundary to reproduce conditions within Earth and indicate how the mantle controls core dynamics. Comparing these simulations to recent global magnetic field models, based on observational data spanning tens of thousands of years, they successfully reproduce the morphology and secular variation of Earth's modern field and the inferred large-scale flow structure at the top of the core. These simulations reveal that the long-term geomagnetic signatures of thermal core-mantle interactions are evident in the longitudinal structure of the geomagnetic field as equatorial patches of reverse flux, rather than the high-latitude patches suggested by less Earth-like simulations. Comparison of these simulations with the field models also suggests that the amplitude of the present-day longitudinal hemispheric imbalance in secular variation is anomalously large, indicating our present-day geomagnetic field may be unusual. The pattern of heat flow across the core-mantle boundary results in longitudinal differences in geomagnetic field behaviour, according to geodynamo modelling.
学科领域	Geosciences, Multidisciplinary
语种	英语
WOS研究方向	Geology
WOS记录号	WOS:000950430500003
来源期刊	NATURE GEOSCIENCE
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/272494
作者单位	University of Leeds
推荐引用方式 GB/T 7714	Mound, Jonathan E. E.,Davies, Christopher J. J.. Longitudinal structure of Earth's magnetic field controlled by lower mantle heat flow[J],2022:15.
APA	Mound, Jonathan E. E.,&Davies, Christopher J. J..(2022).Longitudinal structure of Earth's magnetic field controlled by lower mantle heat flow.NATURE GEOSCIENCE,15.
MLA	Mound, Jonathan E. E.,et al."Longitudinal structure of Earth's magnetic field controlled by lower mantle heat flow".NATURE GEOSCIENCE (2022):15.