The Science Behind Fall Foliage

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What causes the leaves to change color during the fall season?

If you ask me, the pumpkin gets way too much attention during the autumn season. It's the spectacular transformation of leaves that makes this season special.

But did you ever wonder why leaves actually change color before they fall?

It all comes down to the chemical reaction called photosynthesis. In that process, the bright green summer leaves convert sunlight, carbon dioxide, and water into food for plants and oxygen for all living creatures.

As sunlight weakens, photosynthesis slows down and the green pigment called chlorophyll fades, revealing hidden colors of yellows, oranges, and reds.

For a few brief weeks, Mother Nature puts on a last glorious showing of color before the slipping into winter dormancy.

After the leaves fall, trees spend their winter dormancy using food stored from the summer.

Then, with the coming of spring’s sunshine, the cycle begins again as new leaves start to grow.

In 2005, digital imagery from NASA satellites allowed scientists to estimate more than 400 billion trees worldwide support this continuous circle of life.

So what's your favorite place to witness this miracle?