Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 46625 ОРИГИНАЛЬНЫЕ СТАТЬИ ORIGINAL ARTICLES ОРИГИНАЛЬНЫЕ СТАТЬИ Growth of the inner core in the mean-field dynamo model Growth of the inner core in the mean-field dynamo model Reshetnyak M Yu Reshetnyak M Yu Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences, Moscow, Russia ru Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences, Moscow, Russia ru 16 6 1 7 29 10 2021 https://rjes.ru/en/nauka/article/46625/view

Application of Parker's dynamo model to the geodynamo with the growing inner core is considered. It is shown that decrease of the inner core size, where intensive magnetic field generation takes place, leads to the multi-polar magnetic field in the past. This effect reflects the decrease of the region of the effective magnetic field generation. The process is accompanied by increase of the reversals number and decrease of intensity of the geomagnetic field. The constraints on the mechanisms of convection in the liquid core are discussed.

Application of Parker's dynamo model to the geodynamo with the growing inner core is considered. It is shown that decrease of the inner core size, where intensive magnetic field generation takes place, leads to the multi-polar magnetic field in the past. This effect reflects the decrease of the region of the effective magnetic field generation. The process is accompanied by increase of the reversals number and decrease of intensity of the geomagnetic field. The constraints on the mechanisms of convection in the liquid core are discussed.

 Evolution of the Earth magnetic field evolution of the Earth $\alpha$- $\omega$-effects reversals Evolution of the Earth magnetic field evolution of the Earth $\alpha$- $\omega$-effects reversals

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