ArticleProceedings of the National Academy of Sciences of the United States of America2025
Persistent humid climate favored the Qin and Western Han Dynasties in China around 2,200 y ago.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.
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4 citing papers in PubMed.
- Tree growth response and adaptation to climate change and climate extremes: From canopy to stem.Journal of integrative plant biology · 2026Review
- Decadal East Asian monsoon anomalies and implications for societal conflicts.Science advances · 2026Article
- Persistent humid climate favored the Qin and Western Han Dynasties in China around 2,200 y ago.Proceedings of the National Academy of Sciences of the United States of America · 2025Article
- Hydroclimatic instability accelerated the socio-political decline of the Tang Dynasty in northern China.Communications earth & environment · 2025Article
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18 authors.
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Abstract
The Qin and Western Han dynasties (221 BCE to 24 CE) represent an era of societal prosperity in China. However, due to a lack of high-resolution paleoclimate records it is still unclear whether the agricultural boost documented for this period was associated with more favorable climatic conditions. Here, multiparameter analysis of annually resolved tree-ring records and process-based physiological modeling provide evidence of stable and consistently humid climatic conditions during 270 to 77 BCE in northern China. Precipitation in the Asian summer monsoon region during the Qin-Western Han Dynasties was ~18 to 34% higher compared to present-day conditions. In shifting agricultural and pastoral boundaries ~60 to 100 km northwestward, possibility up to 200 km at times, persistently wetter conditions arguably increased food production, contributing to the socioeconomic prosperity around 2,200 y ago. A gradual wetting trend in the western part of arid northwestern China since the 1980s resembles the historical climate analogue, suggesting that similar benefits for regional environmental and agricultural systems may reoccur under current climate change, at least in the near term.
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