How the solar dynamo operates remains enigmatic. The magnetic fields generated by it drive space weather and climate, hence it is of utmost importance for the society to understand it better. The current numerical models have the potential to contribute significantly to our understanding of the solar dynamo, and its stellar counterparts, but so far, these models have had only limited success.
The operation of the large-scale dynamo (LSD), producing the cyclic part of the solar and stellar magnetic fields, is still poorly reproduced and explained. Similarly, the differential rotation profiles do not match the observed ones. Furthermore, there is another dynamo instability, namely the small-scale dynamo (SSD), generating a non-cyclic, fluctuating magnetic field component.
There is boosting interest in trying to understand the role of the SSD in remedying the problems encountered in reproducing the solar cycle and differential rotation. Including all these ingredients in one and the same numerical model, however, requires extraordinary resources. This project proposes to run global convection simulations with GPU-accelerated MHD solver (Pencil Code - Astaroth; PC-A) to study these processes in an unprecedented parameter regime.
Maarit Korpi-Lagg, Aalto University, Finland