A Study on the Climate in the Area of the Middle of Yangtze River from the Zhanguo Period to the East Han Dynasty
Chen Yexin (Department of History,Shanghai Jiaotong University,Shanghai, 200240)
From the Zhanguo period to the East Han Dynasty,the Climate in the Area of the middle of Yangtze River changed frequently. At the beginning of the Zhanguo period,it was warm and wet. From the middle of the Zhanguo period to the late of Hanwu Emperor, it was less warm,and there were many chill events. During B.C.100 and the early of the 1st century,it was warm and wet again. But during the Xin Dynasty and Ming Emperor,it became cold. After that,it was warmer,especially in winter. In the last phase of the East Han,it was colder than before,but which indicated the beginning of large scale temperature decline in the 3rd century. Although there were many changes during this,compare with today,it was relative warm or identical. In the meantime,it alternated between dryness and wetness.