• Corpus ID: 117821113

Sign of helicity in the $\alpha$-$\Omega$ geodynamo

  title={Sign of helicity in the \$\alpha\$-\$\Omega\$ geodynamo},
  author={Xing Wei},
  journal={arXiv: Earth and Planetary Astrophysics},
  • Xing Wei
  • Published 2 August 2010
  • Geology, Physics
  • arXiv: Earth and Planetary Astrophysics
In this paper we discuss the sign of helicity in the $\alpha$-$\Omega$ dynamo and propose a wave-$\Omega$ model in which the $\alpha$ effect in the geodynamo is induced by helical wave but not helical flow as in the solar dynamo. We then tentatively interpret the mechanisms of the Earth's magnetic westward drift, tilt angle, and dipole reversals. 


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