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Earlier, and even earlier, springs in temperate zones

Posted by ewolkovich on 11 Feb 2013 at 02:37 GMT

This is a very interesting paper tackling what is certainly an important and current topic in the climate change literature -- how far can earlier and earlier springs go on for with warming temperatures? We know for a handful of species that at some point this linear relationship between temperatures and advancing dates of flowering should stop because a photoperiod limit will kick in, but this work shows that the phenological start of spring of two of the hottest years on record now is still advancing as predicted by previous (lower) temperatures on record.

What I found most interesting is that in both datasets (and for Concord in both years) the actual mean flowering dates are at the earlier edge of the prediction intervals. We're still within the predicted range. However, while what we may predict based on physiological work is smaller responses with hotter temperatures -- we're seeing the opposite: things are advancing more than we expect on average. It will be interesting to see if this is driven by certain species far more than others and what might explain this species-level variation. The Primack and Davis labs have already done an impressive job of documenting how species differences drive varying responses to warmer springs and I will be interested to see how their labs continue to unravel these results in the future.

No competing interests declared.