By 2100, plants will green up 22.3 days earlier in much of the US, with the biggest jump on spring occurring in western states, they said. In the Pacific northwest, researchers expect an even shorter winter with spring beginning up to 28.5 days earlier by the end of the century. The findings, published on Wednesday in Environmental Research Letters, suggest even bigger shifts in the plant calendar due to climate change than had previously been expected. Earlier this year, another team of researchers suggested that spring was arriving as much as 14 days earlier in most parts of North America because of climate change.
The researchers from the Hawthorne Valley Farmscape Ecology Program drew on thousands of records, from frog mating calls to bird migration patterns, and tree and plant flowerings, to compare the shift in timing of natural events. In some parts of the US, including Wisconsin, some flower species, such as wild geranium, were blooming 24 days earlier in 2012 than in 1945. The newest group of researchers, from US government scientific agencies as well as universities, combined historical records of lilac and honeysuckle growth with 19 climate models to project first leaf and first bud in the coming decades. “We know spring is getting earlier, but we provide actual evidence for how much earlier,” said University of Wisconsin-Madison ecologist Andrew Allstadt, who was part of the research team.
The change would have far-reaching effects — for farming, other industries and the natural world. “The timing of events is important,” Allstadt said. “If plants are shifting earlier in the year, there is a worry that the animals that depend on the plants won’t keep up with those shifts.” Those living in warmer parts of the US, such as the south, are unlikely to see as big a difference in the arrival of spring, because it is already so warm.
US to get earlier springs: scientists - Taipei Times