两汉时期气候状况的历史学再考察

A Historical Re-investigation of Climatic Conditions during the West and East Han Dynasties

本文从农事活动时节、物候和干湿状况三个方面对两汉时期的气候情状进行了历史学的再考察。认为 :在冷暖变动方面 ,两汉时期的气温比其前的春秋时期气温要低 ;与今天相比较无大差异 ,仅有的区别在于具体的变动幅度上 ;前、后汉相比 ,西汉略冷 ,东汉稍暖 ,但其间有多次波动 ,东汉末年 ,气候急剧转冷。在干湿状况方面 。

This historical re investigation of climatic conditions during the West and East Han dynasties (206 BC—220 AD) takes up three aspects: farm work seasons, phenology and degrees of humidity. With changes in temperature, the temperature during the East and West Han dynasties was lower than in the Spring and Autumn Period and was similar with that of today, but the ranges of fluctuation was somewhat different. As for differences between the two periods of West Han and East Han themselves, it was, generally speaking, slightly colder during the West Han than during the East Han. However, there was a steep drop in temperature at the end of the East Han dynasty. In humidity, there were markedly contrasting periods of dry and humid periods during the West and East Han dynasties.