Magnetic Field Variations in Geodynamo Models

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An increase in the intensity of heat sources in the Earth’s core leads to a decrease in the intensity of the dipole magnetic field. The spatial spectrum of the magnetic field becomes multipole. The intensity of variations of the magnetic dipole and its deviations from the rotation axis increases. The dependence of the duration of magnetozones of constant polarity depends on the amplitude of the magnetic dipole according to a power law. The exponent of the power function can change by a factor of two depending on the dipole amplitude. Superchrons of the magnetic field correspond to high intensity of the magnetic dipole.

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作者简介

М. Reshetnyak

Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences

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Email: m.reshetnyak@gmail.com
俄罗斯联邦, Moscow

参考

  1. Зельдович Я.Б., Рузмайкин А.А., Соколов Д.Д. Магнитные поля в астрофизике. М.: Наука. 1988.
  2. Краузе Ф., Рэдлер К.-Х. Магнитная гидродинамика средних полей и теория динамо. М.: Мир. 1984.
  3. Паркинсон У. Введение в геомагнетизм. М.: Мир. 1986.
  4. Решетняк М.Ю. Адаптация модели среднего поля в геодинамо // Физика Земли. 2017. № 4. С. 93–99.
  5. Решетняк М.Ю. Инверсии геомагнитного поля: ограничение на интенсивность конвекции в ядре Земли? // Геомагнетизм и аэрономия. 2021. Т. 61. № 2. С. 267–272.
  6. Abe Y. Physical state of the very early earth // Lithos. 1993. V. 30. № 3–4. P. 223–235.
  7. Bono R.K., Paterson G.A., Biggin A.J. MCADAM: A continuous paleomagnetic dipole moment model for at least 3.7 billion years // Geophys. Res. Lett. 2022. V. 49. P.1–10.
  8. Chandrasekhar S. Hydrodynamic and hydromagnetic stability. Courier Corporation. 1970.
  9. Christensen U.R., Aubert J. Scaling properties of convection-driven dynamos in rotating spherical shells and application to planetary magnetic fields // Geophys. J. Int. 2006. V. 166. № 1. P. 97–114.
  10. Christensen U.R., Aubert J., Hulot G. Conditions for earth-like geodynamo models // Earth Planet. Sci. Lett. 2010. V. 296. № 3—4. P. 487–496.
  11. Panovska S., Constable C. G., Korte M. Extending global continuous geomagnetic field reconstructions on timescales beyond human civilization // Geoch. Geophys. Geos. 2018. V. 19. P. 4757–4772.
  12. Rüdiger G., Hollerbach R., Kitchatinov L.L. Magnetic processes in astrophysics: theory, simulations, experiments. John Wiley & Sons. 2013.
  13. Wicht J. Inner-core conductivity in numerical dynamo simulations // Phys. Earth Planet. Int. 2002. V. 132. № 4. P. 281–302.
  14. Wicht J., Sanchez S. Advances in geodynamo modelling // Geophys. Astr. Fluid Dyn. 2019. V. 113. P. 2–50.

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2. Fig. 1. Time-averaged dependence of the axisymmetric dipole amplitude, kinetic and magnetic energies on the Rayleigh number in the range Ra = (3 − 6) 104 with a step of 5 · 103.

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3. Fig. 2. Dependence of the mean-square deviation of the axisymmetric dipole, kinetic and magnetic energies on the Rayleigh number (upper figure) and of the normalised mean-square deviations of the axisymmetric dipole from the axis of rotation, kinetic and magnetic energies on the Rayleigh number (lower figure).

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4. Fig. 3. Dependence of the time-averaged deviation of the axisymmetric dipole from the axis of rotation and the standard deviation.

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5. Fig. 4. Dependence of the duration of the constant polarity zone τ on the axisymmetric dipole strength. The figure also shows approximations of some fragments of the curve by degree functions.

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