VARIATIONS IN THE GEOMAGNETIC FIELD AND IN THE RATE OF THE EARTH'S ROTATION,
Abstract
Vestine and Kahle, in a previous paper, found a strong correlation between motion of the geomagnetic eccentric dipole and changes in the earth's rotation rate, as inferred from astronomical data. This correlation suggested that the irregular change in length of day was compensated by a change in angular momentum of the outer core which is related to the eccentric dipole motion. New data are used to improve these curves, and the significance of the results is further analyzed. The observed lag in phase between the mantle and magnetically inferred core motion can be explained by diffusion of the magnetic signal through a conducting mantle, which conversely gives an independent estimate of the mantle conductivity. Results of numerical calculations for the phase lag and associated distortions of the apparent eccentric dipole motion are presented. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1968
- Accession Number
- AD0678866
Entities
People
- Anne B. Kahle
- E. H. Vestine
- R. H. Ball
Organizations
- RAND Corporation