Are Occurrences of Traffic Accidents Statistically Affected by Solar Activities?

In recent years, with the development of economy and transportation activities in China the traffic-accident rate in China is rapidly increasing. In this study we investigate statistical correlations between traffic-accident occurrences and solar activities. We base our study on the data of annual-average solar 10cm radio fluxes and annual numbers of traffic accidents in China from 1951 to 2009. We use statistical techniques such as the empirical mode decomposition analysis, periodicity analysis, auto-correlation analysis, and cross-correlation analysis. Our results show that occurrences of traffic accidents are statistically significantly correlated with the 11-year cycles of solar activities. By recognizing that traffic accidents are not only closely related to human activities but also affected by solar activities, we discuss possible causes of the statistical correlations.