关键词: 气候振动, 台风, 饥荒, 粮食, 1949年, 年值, 湿润指数, 广东省, 气候事件, 偏回归平方和

Abstract: In this paper, an attempt has been made to study the climatic fluctuation during the period 1400-1949 AD in Guangdong province, and discuss how it effects food production and causes cyclic fluctuation of famines and bumper harvests. All the data are collected from chronological records of regional geography that called Fangzhi in Chinese.From power spectrum analysis, the fluctuation of severe cold has cycles of about 2-3 decades and 15 decades. Flood and drought have their own cycles, such as 23.1 yr cycle for flood and 30.0 yr cycle for drought, both exceeding 95% of confidence limit. It seems that the long-period fluctuation of typhoon fluctuates similarly in phase with severe cold. Drought and flood occurred freq uently in the cold period, meanwhile the index of humidity decreased. These evidences imply that during the Little Ice Age the variability of precipitation increased, the annual precipitation decreased, and the climate of Guangdong became more continental.The occurrence of famine depends on the degree of flood damage, cold damage and drought damage, especially on the impact of the last one. The slighter the damages of flood, drought and severe cold, the more frequent of bumper harvest.Typhoon is another effective factor on food production. The magnitude of decade value of typhoon presents a negative correlation with the decade value of famine, but a positive one with that of bumper harvest. Undoubtedly, invasions of typhoon destroy crops and incur losses of both life and wealth to inhabitants along the coast. But, on the other side, typhoon carries abundant rainfall to vast areas. When the Pacific High persists in summer, rainfall carried by typhoon can satisfy the water needs for crops.A schematic diagram correlating climate, famine and bumper harvest in this article may be considered as a preliminary conclusion