1206.2106 (Bidya Binay Karak et al.)

Turbulent Pumping of Magnetic Flux Reduces Solar Cycle Memory and thus Impacts Predictability of the Sun's Activity    [PDF]

Bidya Binay Karak, Dibyendu Nandy

Prediction of the Sun's magnetic activity is important because of its effect on space environmental conditions and climate. However, recent efforts to predict the amplitude of the solar cycle have resulted in diverging forecasts with no consensus. It is understood that the dynamical memory of the solar dynamo mechanism governs predictability and this memory is different for advection- and diffusion-dominated solar convection zones. By utilizing stochastically forced, kinematic dynamo simulations, we demonstrate that the inclusion of downward turbulent pumping of magnetic flux reduces the memory of both advection- and diffusion-dominated solar dynamos to only one cycle; stronger pumping degrades this memory further. We conclude that reliable predictions for the maximum of solar activity can be made only at the preceding minimum and for more accurate predictions, sequential data assimilation would be necessary in forecasting models to account for the Sun's short memory.

View original: http://arxiv.org/abs/1206.2106