Impacts of global warming on phenology of spring leaf unfolding remain stable in the long run

Abstract

The impact of spring temperature forcing on the timing of leaf unfolding of plants (temperature sensitivity, S) is one important indicator of how and to what degree plant species track climate change. Fu et al. (Nature 526:104-107, 2015) found that S has significantly decreased from the 1980-1994 to the 1999-2013 period for seven mid-latitude tree species in Europe. However, long-term changes in S over the past 60 years are still not clear. Here, using in situ observations of leaf unfolding for seven dominant European tree species, we analyze the temporal change in S over decadal time scales extending the data series back to 1951. Our results demonstrate that S shows no statistically significant change within shifting 30-year windows from 1951 to 2013 and remains stable between 1951-1980 and 1984-2013 (3.6 versus 3.7 days °C). This result suggests that the significant decrease in S over the past 33 years could not be sustained when examining the trends of phenological responses in the long run. Therefore, we could not conclude that tree spring phenology advances will slow down in the future, and the S changes in warming scenarios are still uncertain.

Long-term linear trends mask phenological shifts

“…We are very happy to see that the article from Wang et al (2016) confirmed these finding using a 15-year window, despite using only 927 species-sites combinations, which is about one sixth of the species-sites (5472) used in our study. However, we can not agree with the highlighted conclusion that the significant decrease in ST using 15-year window is not sustained when examining longer term phenological responses to climate warming.…”

“…1980Fu et al ( -1994Fu et al ( and 1999Fu et al ( -2013. The red line shows the ST in Wang et al (2016) over the period 1980-2013. …”

Trends and Variability in Temperature Sensitivity of Lilac Flowering Phenology

“…In this study, we only analyzed four potential factors impacting the estimate of S T . However, other influencing factors of S T also existed, including changes in tree age, nonlinear responses of plant development to temperature, and microclimate (Menzel et al, ; Vitasse, ; H. Wang, Rutishauser, et al, ). In the future, if we could manipulate environmental factors separately through experiments, the relative importance of individual factor or the interaction effect of several factors on the S T of plant phenology could be determined.…”

“…The S T of leaf phenology of seven European species declined from a cold period (1980–1994) to a warm period (1999–2013), partly due to the reduced chilling (Fu et al, ). However, when comparing the difference in S T between 1951–1980 and 1984–2013 period, the S T of leaf phenology remained stable (H. Wang, Rutishauser, et al, ). The warming experiment using saplings of three woody plants showed that S T of leaf‐out increased at low and moderate warming (Fu et al, ).…”

Impact of Climate Variability on Flowering Phenology and Its Implications for the Schedule of Blossom Festivals

“…In temperate regions, these phenophases are very sensitive to small changes in temperature [11][12][13]. The advancement in flowering dates is estimated as 1 to 12 days for each 1 • C increase in spring temperature [14][15][16]. Recent studies demonstrated that the flowering date of main woody plants in temperate regions shifted towards earlier by a rate of 2.0 to 9.6 days decade −1 over the last few decades across Europe [17,18], East Asia [19,20], and North America [21,22].…”