Research shows that rain-making ceremonies appear more common and effective in regions where dry spells increase the odds of precipitation. An analysis of customs across 1290 ethnic groups supports this pattern.
Economist José-Antonio Espín-Sánchez at Yale University led the study, published in the Quarterly Journal of Economics. His team matched historical reports of rituals with detailed climate records. Groups in areas where rain probability rises after dry days showed a 44 percent rate of such customs, compared with 30 percent elsewhere.
Examples include dragon-invoking practices in China around AD 1000 and seven centuries of special Catholic prayers in Murcia, Spain. The study notes that rituals timed near the end of dry seasons or followed by repeat ceremonies gain apparent success from natural cycles.
Independent experts Simon Papalexiou and Kevin Hong described the statistical mechanism as plausible. They pointed to both true duration dependence and seasonal timing as factors that can reinforce belief in the rituals.
Espín-Sánchez also modeled how leaders who schedule ceremonies just before rain returns are more likely to retain influence, helping such practices persist.
