Project Details
Projekt
Alternative driving mechanisms for the geodynamo: Precession and double diffusive convection
Applicant
Professor Dr. Andreas Tilgner
Subject Area
Geophysics
Term
from 2004 to 2009
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 5428672
A large number of simulations of the geodynamo exist in which the flow in the Earth's core is assumed to be driven by convection alone. However, it is possible that precession is actually driving the geodynamo by drawing on the rotational energy stored in the Earth-Moon system. A precession driven dynamo implies potentially observable effects on the motion of the Earth and the Moon. If indeed the geodynamo is convectively driven, the magnetic field is likely to be maintained by compositional convection with some admixture of thermal convection, so that we are dealing with double diffusive convection. The present proposal intends to elucidate whether a precession driven dynamo is accessible numerically, whether there are observable consequences of precession driving the dynamo, and whether there are qualitatively new effects introduced by double diffusion should the geodynamo be driven by compositional convection.
DFG Programme
Priority Programmes
