关键词: 气候信息, 熵, 评价, 准确率

Abstract: This paper documents methods of evaluating the climatic information extracted from Ch-inese historical literatures. Relevant sources include local gazettes, official histories, memorial to the emperor and personal and private writings. Some indexes has been developed to modify climatic information in three aspects, they are: the time interval between the climatic event occurred and when it was recorded, the distant between the event and where it was recorded, and the ability in language of the writer's explanation. After some numerical treatments, it shows that:(1)The realiability of climatic informa-tion is not only determined by the accuracy of the data, but also by the distribution and resolu-tion of the data. (2) The more grades divided, the more uncertainty will appears. (3) The lar-ger variance schedulled, the more information would be available.

Key words: Climatic information, Entropy analysis, Evaluating and accuracy