A recent paper, published in Geophysical Research Letters, has found that by the year 2100, spring may come up to five weeks earlier in the northern U.S. and more than a week earlier in the southern U.S.
Naturally, the earlier onset of the spring season is believed to bring forth a major change in the ecosystems of the areas affected. Why? The change in weather (and temperature) will require species to adapt—some will adapt easily and others will struggle as the ecosystem change alters their food sources. As it is, there are plenty of other ways the environment is changing—including rising sea levels, more frequent droughts, and more intense blizzards.
Climate Central shares:
The idea that spring is getting pushed earlier by climate change isn’t new: in fact, scientists have already demonstrated that spring weather has been coming to the U.S. three days earlier during the past 30 years, on average, than it did during the previous 30. Others have documented the shifting, not of weather, but of phenology — that is, biological events of all sorts, including budburst, but also flowering, ovulation, migration and other seasonal changes in plants and animals.
This is the first study that looks in such depth at a single phenomenon. About a quarter of the CO2 emitted through human activity is re-absorbed by the land, mostly by plants (another quarter goes into the sea, and half remains in the atmosphere where it traps the Sun’s energy).
Much of that absorption happens in spring and summer, when plants are most actively growing — if you look at a chart of atmospheric CO2, you see it rise over the years in a sawtooth pattern, with a slight drop every year during the growing season, followed by an even bigger increase in the fall, as leaves fall and plants die.
Lead author David Medvigy, an ecologist at Princeton University, and his co-authors used data on budburst and local temperature provided by the National Phenology Network, an organization that uses citizen-scientists to report, and used art climate models to see how temperature change would impact leaf emergence in the decades to come.
“The main result is the obvious one: it’s going to be warmer, so budburst is going to be earlier,” said Medvigy to Climate Central. “The typical value is two weeks, but in some cases, it’s a month or more, while in others it’s seven days.”