Comparative Analysis of Extreme Drought Events and Social Impacts in Henan Province During the Middle Ming Dynasty

The analysis of historical climate change events can deepen the understanding of climate impacts and provide historical examples of coping with extreme events like drought. The data from historical records on droughts and famines were collected during the Chenghua drought (1483-1485 AD), Jiajing drought (1527-1529 AD) and Wanli drought (1584-1589 AD) in Henan Province in the Mid Ming Dynasty. Based on this, the average drought index (ADI), average famine index (AFI) and the average social regulation index (ASRI) were defined to quantitatively explore the differences in the social impacts of extreme droughts. The results were as follows: (1) As for ADI, the Wanli drought was the most severe (1.59), followed by the Jiajing drought (1.21) and the Chenghua drought (1.02). In terms of AFI, the famine conditions were the most severe during the Jiajing drought (0.43), followed by Chenghua drought (0.30) and the Wanli drought (0.15). (2) The ASRI values in the Chenghua drought, Jiajing drought and Wanli drought were 3.90, 3.90 and 4.54, respectively. It could be concluded society showed the highest social regulation ability during the Wanli drought and showed the same level of the two other droughts. However, for the key years, the social regulation ability of the Jiajing drought was higher than that of Chenghua drought, especially in the alleviation of low-grade drought. (3) From historical documents, the progress of agricultural technology, the progress of famine relief policy and the change in relief supplies greatly improved the social ability to cope with the extreme drought events.