English

Modelling the Solar Cycle Nonlinearities into the Algebraic Approach

Solar and Stellar Astrophysics 2025-11-06 v1 Computational Physics Fluid Dynamics

Abstract

Understanding and predicting solar-cycle variability requires accounting for nonlinear feedbacks that regulate the buildup of the Sun's polar magnetic field. We present a simplified but physically grounded algebraic approach that models the dipole contribution of active regions (ARs) while incorporating two key nonlinearities: tilt quenching (TQ) and latitude quenching (LQ). Using ensembles of synthetic cycles across the dynamo effectivity range λR\lambda_R, we quantify how these mechanisms suppress the axial dipole and impose self-limiting feedback. Our results show that (i) both TQ and LQ reduce the polar field, and together they generate a clear saturation (ceiling) of dipole growth with increasing cycle amplitude; (ii) the balance between LQ and TQ, expressed as R(λR)=dev(LQ)/dev(TQ)R(\lambda_R) = \mathrm{dev(LQ)}/\mathrm{dev(TQ)}, transitions near λR12\lambda_R \approx 12^\circ, with LQ dominating at low λR\lambda_R and TQ at high λR\lambda_R; (iii) over 8λR208^\circ \leq \lambda_R \leq 20^\circ, the ratio follows a shallow offset power law with exponent n0.36±0.04n \approx 0.36 \pm 0.04, significantly flatter than the n=2n=2 scaling assumed in many surface flux--transport (SFT) models; and (iv) symmetric, tilt-asymmetric, and morphology-asymmetric AR prescriptions yield nearly identical R(λR)R(\lambda_R) curves, indicating weak sensitivity to AR geometry for fixed transport. These findings demonstrate that nonlinear saturation of the solar cycle can be captured efficiently with algebraic formulations, providing a transparent complement to full SFT simulations. The method highlights that the LQ\--TQ balance is primarily controlled by transport (λR\lambda_R), not by active-region configuration, and statistically disfavors the SFT-based 1/λR21/\lambda_R^{2} dependence.

Keywords

Cite

@article{arxiv.2511.03611,
  title  = {Modelling the Solar Cycle Nonlinearities into the Algebraic Approach},
  author = {Mohammed H. Talafha},
  journal= {arXiv preprint arXiv:2511.03611},
  year   = {2025}
}

Comments

22 pages, 10 figures; Solar Physics Journal, Accepted: 29 October 2025

R2 v1 2026-07-01T07:23:06.272Z