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How could phenological records from the Chinese poems of the Tang and Song Dynasties (618–1260 AD) be reliable evidence of past climate changes?

Phenological records in historical documents have been proved to be of unique value for reconstructing past climate changes. As a literary genre, poetry reached its peak period in the Tang and Song Dynasties (618-1260 AD) in China, which could provide abundant phenological records in this period when lacking phenological observations. However, the reliability of phenological records from poems as well as their processing methods remains to be comprehensively summarized and discussed. In 15 this paper, after introducing the certainties and uncertainties of phenological information in poems, the key processing steps and methods for deriving phenological records from poems and using them in past climate change studies were discussed: (1) two principles namely the principle of conservative and the principle of personal experience should be followed to reduce the uncertainties; (2) the phenological records in poems need to be filtered according to the types of poems, the background information, the 20 rhetorical devices and the spatial representations; (3) the animals and plants are identified to species level according to their modern distributions and the sequences of different phenophases; (4) the phenophases in poems are identified on the basis of modern observation criterion; (5) the dates and sites for the phenophases in poems are confirmed from background information and related studies. Finally, the temperature anomalies reconstructed by phenological records from poems were compared with those 25 reconstructed by other historical documents in published studies to demonstrate the validity and reliability of phenological records from poems in studies of past climate changes. This paper proved that the phenological records from poems could be useful evidence of past climate changes after being https://doi.org/10.5194/cp-2020-122 Preprint. Discussion started: 28 September 2020 c © Author(s) 2020. CC BY 4.0 License.