"Humans Are Altering Fall Foliage, Studies Find"
by Cole Mellino
Fall foliage may be changing later due to climate change. As certain regions experience warmer average temperatures, the growth season has been extended, causing leaves to change colors and drop later than in the past. Studies from Europe and Japan show that trees are starting to change colors and drop later, so researchers are looking at whether the phenomenon is happening in the U.S. too.
There have been no comprehensive studies performed in the U.S. yet. But a recent AP story on various pieces of research shows that the trend may be taking place:
Researchers at the NASA Goddard Space Flight Center and at Seoul National University in South Korea used satellites to show the end of the growing season was delayed by 6 1/2 days from 1982 to 2008 in the Northern Hemisphere.
In Massachusetts, the leaves are changing about three days later than they were two decades ago at the Harvard Forest 65 miles west of Boston, according to data collected by John O’Keefe, a retired Harvard professor and museum coordinator who’s continuing to collect data.
In New Hampshire, data collected at the federal Hubbard Brook Experimental Forest in Woodstock suggests sugar maples are going dormant two to five days later than they were two decades ago.
In Vermont, state foresters studying sugar maples at the Proctor Maple Research Center in Underhill found that the growing season ended later than the statistical average in seven out of the last 10 years.
Researchers at the National Phenology Network have spent the last four years coming up with standards to be used by observers in reporting foliage color changes. These standards are due out in the next couple weeks. The U.S. Geological Survey is using satellites from NASA and the National Oceanic and Atmospheric Administration to look at fall foliage from space.
— Cole Mellino is an intern with the energy team at the Center for American Progress