Science Seminars

7/31/2017 – Deniz Ölçek; Long-term Solar Variability and Intermittency in a 2X2D Babcock-Leighton Model

Speaker: Deniz Ölçek (Université de Montréal)
Date: Friday, Jul 31, 2020
Time: 4:00 PM
Location: SPSC W120

Seminar Abstract:

In this talk, I will present a numerical model (Lemerle & Charbonneau, 2015) of the solar cycle based on the Babcock-Leighton mechanism of poloidal field regeneration by the surface decay of bipolar magnetic regions. The model is called 2X2D because it is based on the coupling of a surface flux transport simulation with a mean-field-like interior dynamo model. In other words, it couples two two-dimensional simulations. It is well-suited for providing synthetic data for coronal magnetic field reproductions as well as for solar cycle forecasting and exploring the long-term solar-like variability. Recently, the alpha effect, the mechanism that reinforces the poloidal field from an existing toroidal field when the surface decay is not sufficient to keep the main dynamo running, is included in the simulation. Furthermore, the model can exhibit intermittency, i.e. strongly reduced Maunder Minimum-like episodes in an irregular fashion between epochs of solar-like cyclic behavior due to stochasticity inherent to emergence statistics. Besides introducing the model, I will also briefly talk about the reconstruction of the past long-term solar activity with indirect solar proxies such as cosmogenic isotopes, the statistics of grand minima reconstructed with this method and its comparison with our simulation results.