《Weather Shocks》.pdf

The Economic Journal, 124 (March), 92–118. Doi: 10.1111/ecoj.12037 © 2013 The Author(s). The Economic Journal © 2013 Royal Economic Society. Published by John Wiley Sons, 9600 Garsington Road, Oxford OX4 2DQ, UK and 350 Main Street, Malden, MA 02148, USA. WEATHER SHOCKS, SWEET POTATOES AND PEASANT REVOLTS IN HISTORICAL CHINA* Ruixue Jia I use data covering 267 prefectures over four centuries to investigate two questions about historical China. To what extent did weather shocks cause civil conflict? And to what extent did the historical introduction of (drought resistant) sweet potatoes mitigate these effects? I find that before the introduction of sweet potatoes, exceptional droughts increased the probability of peasant revolts by around 0.7 percentage points, which translates into a revolt probability in drought years that is more than twice the average revolt probability. After the introduction of sweet potatoes, exceptional droughts only increased the probability of peasant revolts by around 0.2 percentage points. In recent years, historians and climatologists have found evidence of a link between weather-induced economic decline and conflict for ancient Egypt (Fagan, 2009), the Classic Mayan culture (Diamond, 2006; Yancheva et al., 2007) and the Qing and Tang Dynasties in China (Hinsch, 1988; Yancheva et al., 2007). I contribute to this research using data covering 267 prefectures over more than four centuries to investigate two questions about historical China. To what extent did weather-induced bad harvests cause civil conflict? And to what extent did the historical introduction of (drought resistant) sweet potatoes mitigate these effects? Historical China is a good testing ground for the link between weather shocks and civil conflict as there is detailed information on a