A two-wave dynamo model by Zharkova et al. (2015) disagrees with data on long-term solar variability

TL;DR

This paper evaluates Zharkova et al.'s two-wave dynamo model's predictions of solar activity over the past 800 years and finds it inconsistent with observed data, questioning its reliability for future forecasts.

Contribution

The study critically assesses the accuracy of Zharkova et al.'s long-term solar activity model against historical data, revealing significant discrepancies.

Findings

Zharkova et al.'s model does not match historical solar activity features.

The model's predictive reliability for future solar activity is questionable.

Historical data contradict the model's long-term predictions.

Abstract

A two-wave dynamo model was recently proposed by Zharkova et al. (2015, Zh15 henceforth), which aims at long-term predictions of solar activity for millennia ahead and backwards. Here we confront the backward model predictions for the last 800 years with known variability of solar activity, using both direct sunspot observations since 1610 and reconstructions based on cosmogenic radionuclide data. We show that the Zh15 model fails to reproduce the well-established features of the solar activity evolution during the last millennium. This means that the predictive part for the future is not reliable either.