Tidal dissipation and the strength of the Earth’s internal magnetic field

  title={Tidal dissipation and the strength of the Earth’s internal magnetic field},
  author={Bruce A. Buffett},
  • B. Buffett
  • Published 16 December 2010
  • Geology, Physics
  • Nature
Magnetic fields at the Earth’s surface represent only a fraction of the field inside the core. The strength and structure of the internal field are poorly known, yet the details are important for our understanding of the geodynamo. Here I obtain an indirect estimate for the field strength from measurements of tidal dissipation. Tidally driven flow in the Earth’s liquid core develops internal shear layers, which distort the internal magnetic field and generate electric currents. Ohmic losses… 

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