If you are like me, you marvel at the vibrant color of fall's beautiful leaves. I crave the reds especially, and look for changes every time I'm outside in the fall months. But what gives the leaves those bright, red colors?

Anthocyanins are the pigments that give fall leaves their stunning reds, purples and pinks. As days shorten and temperatures drop, chlorophyll, the green pigment in leaves, fades, revealing carotenoids (yellows and oranges) and allowing anthocyanins to shine.

Unlike carotenoids, anthocyanins are actually produced in the leaf in response to bright light and cool nights, creating those fiery hues that make autumn so magical.

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Weather plays a big role in the show. Sunny days — paired with cool, but not freezing, nights — stimulate anthocyanin production, resulting in the most vivid reds and purples. Overcast days or early frosts can dull the colors, which is why some autumns are more spectacular than others.

While anthocyanins are best known for coloring leaves, they also appear in fruits like apples, grapes and berries. In both leaves and fruits, these pigments act as a natural sunscreen and antioxidant, protecting plant tissues from stress.

So when you admire the reds of maple trees or the purples of mountain ash berries, you’re seeing anthocyanins at work, keeping plants safe while painting the world in color.

Jennifer Gray is a weather and climate writer for weather.com. She has been covering some of the world's biggest weather and climate stories for the last two decades.