Open AccessDissipation at the core‐mantle boundary on a small‐scale topography
Author(s) -
Le Mouël J. L.,
Narteau C.,
GreffLefftz M.,
Holschneider M.
Publication year - 2006
Publication title -
journal of geophysical research: solid earth
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2005jb003846
Subject(s) - dissipation , dissipative system , core–mantle boundary , geophysics , mantle (geology) , physics , cosmic microwave background , core (optical fiber) , inner core , mechanics , geology , boundary (topology) , classical mechanics , anisotropy , optics , thermodynamics , mathematical analysis , mathematics
The parameters of the nutations are now known with a good accuracy, and the theory accounts for most of their values. Dissipative friction at the core‐mantle boundary (CMB) and at the inner core boundary is an important ingredient of the theory. Up to now, viscous coupling at a smooth interface and electromagnetic coupling have been considered. In some cases they appear hardly strong enough to account for the observations. We advocate here that the CMB has a small‐scale roughness and estimate the dissipation resulting from the interaction of the fluid core motion with this topography. We conclude that it might be significant.