Woody plants in Beijing, China, are flowering earlier than they did a few decades ago — in line with changes in mean monthly temperatures.

Beijing has a temperate monsoon climate. At present the average daily maximum in July is 26.3 °C, the average minimum in January reaches ？3.7 °C and the annual mean is 12.2 °C. However, the city has been getting warmer — by 0.47 °C per decade since 1960.

DAI Junhu, GE Quansheng and their colleagues from Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences have compared the temperature records of the Beijing meteorological station with records of the first flowering date of woody plants in the city, as collected by China’s Phenological Observation Network. On average, the 48 species analysed flowered 5.4 days earlier in 2007 than they did when the observation network began work in 1963.

The  researchers also note that many species brought forward their first flowering date more for a given rise in mean monthly temperature between 1990 and 2007, when the global warming signal was stronger, than they did between 1963 and 1989.

The related findings have been published in Adv. Atmos. Sci.. (Bai, J., Q. Ge, and J. Dai*, 2011: The response of first flowering dates to abrupt climate change in Beijing. Adv. Atmos. Sci. 28(3): 564-572)