Correlation analysis between the occurrence of epidemic in ancient China and solar activity

As the globe has witnessed the pandemic, epidemic diseases exert a strong impact on human beings and ecosystems. Since the Sun is the primary energy source of the Earth, some scientific pioneers attempted to search for the discernible relation between solar activity and the incidence of epidemics. In this study, the periodic changes and trends of ancient Chinese epidemic data were analyzed in comparison with those of sunspot numbers, a solar activity proxy. The results show that the epidemic and solar activity changes are in good agreement to a certain extent, especially during the Gleissberg and the de Vries cycles. The wavelet coherence shows that the frequency of the epidemic data and sunspot numbers are highly associated. In addition, results from the ensemble empirical mode decomposition illustrate consistent variations in low-frequency decompositions. This study has important implications for further understanding of the potential impact of solar activity on Earth's biosphere, the underlying mechanism of which needs further exploration.

Automated summary

This study compares the periodic changes and trends of ancient Chinese epidemic data with sunspot numbers, a proxy of solar activity. The results show a good agreement between epidemic and solar activity changes, especially during the Gleissberg and the de Vries cycles. The wavelet coherence analysis indicates a high association between the frequency of epidemic data and sunspot numbers. This study has important implications for understanding the potential impact of solar activity on Earth's biosphere, although further exploration is needed to understand the underlying mechanism.