Comment on the paper by Popova et al. "On a role of quadruple component of magnetic field in defining solar activity in grand cycles"

TL;DR

This paper critically evaluates Popova et al.'s mathematical model of solar activity, highlighting its flaws, inconsistencies with observational data, and limited applicability due to the chaotic nature of solar phenomena.

Contribution

It provides a critical commentary on the limitations and inaccuracies of a proposed solar activity model, emphasizing the importance of realistic assumptions.

Findings

The model is unreliable for long-term predictions due to insufficient data.

The model's results contradict observational data.

Solar activity's chaotic nature limits harmonic prediction methods.

Abstract

The paper by Popova et al. presents an oversimplified mathematical model of solar activity with a claim of predicting/postdicting it for several millennia ahead/backwards. The work contains several flaws devaluating the results: (1) the method is unreliable from the point of view of signal processing (it is impossible to make harmonic predictions for thousands of years based on only 35 years of data) and lacks quality control, (2) the result of post-diction apparently contradicts the observational data. (3) theoretical speculations make little sense, To summarize, a multi-harmonic mathematical model, hardly related to full solar dynamo theory, is presented, which is not applicable to realistic solar conditions because of the significant chaotic/stochastic intrinsic component and strong non-stationarity of solar activity. The obtained result is apparently inconsistent with the data in the past and thus cannot be trusted for the future predictions.