Climate Change and the Pattern of the Hot Spots of War in Ancient China

Abstract

Quantitative research on climate change and war hot spots throughout history is lacking. In this study, the spatial distribution and dynamic process of war hot spots under different climatic phases in imperial China (1–1911 CE) are revealed using Emerging Hot Spot Analysis (EHSA), based on the Global Moran’s Index for testing the degree of spatial autocorrelation or dependency. The results show that: (1) Battles were significantly clustered regardless of any climatic mode or war category. (2) Hot spots for all war were generally located in the Loess Plateau and the North China Plain during warm and wet periods, but in the Central Plain, the Jianghuai region, and the lower reaches of the Yangtze River/Yangtze River Delta during cold and dry conditions. (3) Hot spots for agri-nomadic conflict have similar patterns as those for all war, whereas rebellion hot spots expanded outward during warm and wet intervals yet contracted inward during cold and dry stages. These findings, by providing insightful evidence into the spatiotemporal patterns of war under the movements of climatic-ecological zones and geopolitical variations in ancient China, can be a starting point for future exploration of the long-term relationship between climate change and social security.