Flow modelling (8)

velocity field at CMB

steady flow in drifting frame

• flow steady in a frame tied to the core,
• flow fit on secular variation of magnetic field,
• solid rotation of core relative to mantle,
• “very stiff torsional oscillation”,
• very good fit to variations of LOD. (Holme, Whaler)
• eastward drift provides a better fit than westward to LOD,