This Rutishauser and colleagues have been tracking the blooming of flowers in Switzerland (can you think of a more delightful job as a scientist?). In a paper just published in GRL, they concluded that 2007 was a remarkable spring:
Anomalously high temperatures led to a very early onset of plant phenological spring phases, including 98 record early observations out of a possible total of 302 (32%) for selected phases in Switzerland.
To me, one of the most revealing conversations I’ve had with a scientist was a discussion about the variables that govern the timing of plants leafing out, and flowering, and dropping their leaves. We were walking in the woods, and he explained how relatively poorly studied the question of timing is. It’s the sort of data that, comprehensively collected, would be incredibly useful for climate change studies. But the comprehensive collection of such “phenology” data is still in its infancy.
For more on the importance of this issue and the efforts to collect better data: US National Phenology Network.
(Thanks to Garrulus for the picture.)