Phenological data series of cherry tree flowering in Kyoto, Japan, and its application to reconstruction of springtime temperatures since the 9th century

摘要: Changes in springtime temperature Kyoto, Japan, since the 9th century were reconstructed, using phenological data series for cherry tree (Prunus jamasakura), deduced from old diaries and chronicles. Phenological 732 years was made available by combining previous studies. The full-flowering date of trees fluctuates accordance with conditions during February March. Full-flowering dates closely related to March mean means a accumulation index, which plant growth is considered be an exponential function temperature. Calibration enabled accurate estimation temperatures instrumental period, after 1880; root square error (RMSE) estimates determined within 0.1 °C, smoothing local linear regression over time spans 31 years. results suggested existence four cold periods, 1330–1350, 1520–1550, 1670–1700, 1825–1830, periods estimated 4–5 about 3–4 °C lower than present normal These coincided less extreme known as Wolf, Spoerer, Maunder, Dalton minima, long-term solar variation cycle, has periodicity 150–250 sunspot cycle length, short-term also compared estimates, result that lag 15 detected climatic response variation. Copyright © 2007 Royal Meteorological Society