Interplay of leaf-out drivers and limited advance of spring onset under future climate conditions
IntroductionGlobal warming and early spring
IntroductionDrivers of leaf emergence
IntroductionEarly leaf onset and carbon cycling
Our study aimed to consider all drivers of leaf emergence, untangle their relations, and produce a revised estimate of carbon uptake due to early leafing of temperate trees.
MethodMeasurement and modelling of spring leaf-out
To study the influence of each ecological parameter under future climate, we extrapolated the timing of spring leaf-out until 2100 using our newly developed full model and two climate warming scenarios (RCP 4.5 and 8.5).
Our resultsThe environmental drivers of spring leaf-out
Leafing was previously predicted in vegetation models to advance by about a month by the end of the 21st century but our full-model, considering all drivers, predicted that the advance would be limited to only two weeks.
Our resultsConsequences for future carbon cycling
Conclusion Spring onset, a restricted phenomenon
Thus, although we can already observe an advance in spring arrival in our gardens, it is not expected to exceed two weeks, on average, over the rest of the century. Altogether, this means that, over that period, the total increase in carbon uptake by trees due to the early spring onset will be limited and not be as high as previously estimated (12 Gt vs. 37 Gt).