Climate Change and Harvest in Xi''an since 1736: The High-resolution Data Derived from the Archives in the Qing Dynasty
1736年以来西安气候变化与农业收成的相关分析

Based on snow, rainfall and harvest archives records in the Qing Dynasty (1644-1911 AD), the modern meteorological observation data, the annual winter mean temperature and seasonal precipitation series from 1736 to 2000 and the series of harvest in summer and autumn from 1736 to 1910 are reconstructed. Meanwhile, the characteristics of climate change and the relationship between climate change and harvest are analyzed by using the high-resolution data. The results show: (1) Warm and cold changes in Xi'an have obvious inter-centennial fluctuation. Climate is relatively warm in the 18th century and cold in the 19th century, but turns warm with a rapid warming trend in the 20th century. (2) Precipitation changes have obvious inter-decadal fluctuation, experiencing six rainy periods and seven drought periods in Xi'an since 1736, in which the mean precipitation in the rainy periods is 16% more than that in drought periods. (3) The coefficients between the precipitation from June to August and the harvest in autumn are well correlated, and the precipitation during the period from September to May and the harvest in summer are remarkable.