Revisiting the daily weather information in the Guan Tingfen Diary (Haining, China, 1815–1865)

Abstract. Historical weather diaries provide valuable high-resolution information for investigating past weather and climate variability before instrumental observations. Here, we digitize and systematically categorize weather- and climate-related information from the Guan Tingfen Diary, a nearly continuous daily record from Haining, eastern China, spanning 1815–1865. The diary documents precipitation and sky conditions, together with wind, perceptions on cold/warm, hydrological conditions, unusual phenomena, and societal responses to weather and climate. Descriptive records were converted into standardized categories while retaining their original information as much as possible. Comparisons with other climate datasets show that the diary captures meaningful climatic variability. The high temporal resolution of the diary provides detailed insights into the intra-seasonal evolution of extreme climate events that cannot be resolved by conventional seasonal reconstructions. The diary also contains unusual weather and atmospheric phenomena that may provide additional evidence for investigating the climatic impacts of major volcanic eruptions. These results highlight the value of the Guan Tingfen Diary as a high-resolution documentary climate record and its potential for investigating historical climate variability and extremes and reconstructing daily weather in the early nineteenth century.