Climate Shocks and Sino-nomadic Conflict
利用两千多年的干旱和洪水数据，研究发现降水减少与游牧民族入侵中原正相关，将现代非洲的发现扩展到亚洲历史时期。
Employing droughts and floods to proxy for changes in precipitation, this paper shows nomadic incursions into settled Han Chinese regions over a period of more than two thousand years—the most enduring clash of civilizations in history—to be positively correlated with less rainfall and negatively correlated with more rainfall. Consistent with findings that economic shocks are positively correlated with conflicts in modern sub-Saharan Africa when instrumented by rainfall, our reduced-form results extend this relationship to a very different temporal and geographical context, the Asian continent, and long historical period. © 2011 The President and Fellows of Harvard College and the Massachusetts Institute of Technology.