Global Warming Might Push Back Fall Foliage Transformations

http://www.wunderground.com/news/global-warming-fall-leaves-20140922

Your favorite fall foliage could come later in the year and last longer, thanks to global warming. 

According to a report by Princeton University researchers in Global Ecology and Biogeography, climate change might affect when fall foliage appears in different parts of North America.

In the study, the researchers explained that trees need low daily temperatures and short daylight hours to churn out their famous autumnal shades.

Senior author David Medvigy, an assistant professor of geosciences and associated faculty member at the Princeton Environmental Institute, and first author Su-Jong Jeong discovered that these two factors – daily temperature and daylight hours – not only help predict fall foliage timing, but also influence specific tree species in different ways.

"We're really interested in understanding how these systems will change as we experience global warming or climate change," Medvigy said in a university statement. "What these results are suggesting is that different locations will change in different ways, and that these differences are actually going to be quite interesting."

The researchers studied the American beech, aspen, black oak, northern red oak, paper birch, red maple, sugar maple and sweet birch in order to examine a wide variety of species, the university reports.

During the study, Medvigy and Jeong found that fall foliage timing is more sensitive to temperature changes in warmer areas – meaning Alaska is unlikely to see changes in its fall foliage timing by the end of the century, but Massachusetts’ trees might change a month later than normal. 

Medvigy and his team also noted the economic importance of these possible changes. Later and longer fall seasons will impact the timing of growing cycles, which in turn have an effect on the types of crops planted in a region, the amount of pests present, and animal feeding times. 

"We now have a much better understanding of how temperature, day-length and leaf color are related," Medvigy said. "This understanding will help us make better forecasts for climate, as well as for the basic dynamics of forests. My group is now investigating these issues together with researchers from GFDL."