Like most Minnesotans, I enjoy every minute of autumn. Each year, summer transitions to fall with magnificent colors and temperatures that are perfect for cuddly scarves and sweaters. I’m especially grateful that I get to wear my boots on bike rides without needing a towel. (Yes, it’s gross but necessary in Minnesota’s 90 degree weather and 70 percent humidity!)

I know I’m not alone in noticing that this year’s autumn was one of the longest lasting and most beautiful in many years. In early September, the Minnesota Department of Natural Resources (DNR) reported that this year would be the best year for fall colors in over a decade. But why? Is it because of global warming? Could beautiful fall colors be one of the more enjoyable consequences of climate change?

Well, it isn’t just your next door neighbor that’s wondering. Scientists are wondering too. They don’t quite know for sure if global warming is changing the signs of the season—like it already has with an earlier-arriving spring—but they’re sure as heck trying to figure it out. According to Jana Albers, a DNR forest health specialist, sufficient amounts of rain during the growing season and recent warm days and cool evenings have caused our especially vivid colors this fall. But there are a few other variable combinations that scientists are working to piece together as well.

• Weather is the most critical ingredient in the recipe for fall colors.
• Colors are best when high-quality foliage—a product of a warm, moist summer—is exposed to sunny, cool fall days.
• Light frosts may help but hard freezes can ruin the display.
• Physiological stresses placed on trees can impact fall colors.
• Cool, wet summers can cause premature displays of color.
• A mild summer drought may actually increase the display, but severe drought usually dulls colors noticeably.
• In some cases, foliage may die early and turn straw-colored due to a lack of water.
• Because it’s too dry to produce vibrant reds, yellows, and oranges, severe summer droughts will create a landscape filled with the subtler colors of tans, bronzes, and auburns.

But even with all that, we can’t blame global warming just yet. Scientists need to study long-term patterns in nature’s timing—a type of science called phenology—to determine the exact relationship between fall colors and global warming. This can be a tricky business because, as you can see in the list above, nature doesn’t always work in long-term patterns. Plus, humans love to rely on short-term observations. But according to a story on msnbc.com, phenologists are already starting to see some patterns that could link global warming and fall colors over the long term.

• “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 six and a half 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 7 of the last 10 years.”

Even though I’m grateful for Minnesota’s fall colors and look forward to them every year, I’m not grateful for the possible connection to something larger, looming, and less known. In these last weeks before snow falls (eek!) let’s enjoy the crunch of leaves, but let’s not forget the impact of climate change on Minnesota seasons.

Like most Minnesotans, I enjoy every minute of autumn. Each year, summer transitions to fall with magnificent colors and temperatures that are perfect for cuddly scarves and sweaters.