ABSTRACT:
Great progress has been made in the numerical simulation of planetary dynamos, though these numerical
experiments still operate in a regime very far from real planets. For example, it seems unlikely that viscous
forces are at all significant in planetary interiors, yet the more weakly forced numerical simulations display
a significant dependence on viscosity, and indeed in some simulations the dynamo mechanism itself is viscously
driven, taking the form of helical Ekman pumping within Busse-like convection rolls. Given the similarity of
the external fields observed in the terrestrial planets and gas giants, and the tiny value of the Ekman number
in all such cases, it seems natural to suppose that the underlying dynamo mechanism is simple, robust,
independent of viscosity, and insensitive to mechanical boundary conditions. In this talk one such mechanism
is proposed which relies on the spontaneous emission of inertial waves within the planetary core, driven by
the strong buoyancy flux in the equatorial plane.
ADDITIONAL INFORMATION:
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