Abstract
We have performed numerical magnetohydrodynamic dynamo simulations in a spherical shell with rotational speed or length-of-day (LOD) variation, which is motivated by correlations between geomagnetic field and climatic variations with ice and non-ice ages. The results show that LOD variation leads to magnetic field variation whose amplitude is considerably larger than that of LOD variation. The heat flux at the outer sphere and the zonal flow also change. The mechanism of the magnetic field variation due to LOD variation is also found. The keys are changes of dynamo activity and Joule heating.
- Received 4 May 2013
DOI:https://doi.org/10.1103/PhysRevLett.111.124501
© 2013 American Physical Society
Focus
Simulations Strengthen Earth’s Magnetic-Field/Climate Connection
Published 20 September 2013
Simulations support the idea that during past ice ages, a slightly faster rotation rate for the Earth could have increased its magnetic field.
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