Playing the field: Geomagnetic storms and international stock markets

This paper documents the impact of geomagnetic storms (GMS) on world and country-specific stock market returns. For the world index and for most of the international indices in our sample, we find that the previous week's unusually high levels of geomagnetic activity have a negative, statistically and economically significant impact on today's stock returns. Our results are consistent with psychological theories of "misattribution of mood," since GMS have been found to negatively affect people's judgment and behavior.