The Science of Fall 

By Leia Wolfe 

Fall is one of the most popular seasons of the year. When fall comes around the air get’s cooler and the leaves start to change colors and fall off of the trees, but have you ever wondered why that happens?  

When asked Lenape science teacher Ms. Bowser said, “Chlorophyll which you’ve most likely heard of makes the leaves green. Carotenoid is the pigment responsible for making the leaves orange, yellows, and browns and Anthocyanin is responsible for the more reds, blues, and purples. Chlorophyll absorbs red and blue light from sunlight so these colors are not shown when light is reflected from the chlorophyll molecule, instead it reflects the color green so the leaves are green. Chlorophyll is continuously made by sunlight and warm temperature so green leaves are abundant in the summer. Carotene absorbs the blue green and blue light from sunlight, it reflects yellows, oranges, and browns so you see these colors when they are abundant. Anthocyanins are able to absorb blue, blue green, and green light and reflects a bright red color, if the tree is more acidic it will show a purple color. Once the cells and connecting tissue at the base of the leaf are completely sealed the leaf is ready to fall. When autumn rolls around the nights are longer there is less sunlight which means less chlorophyll, which means no green leaves. The more sugar actually results in more production of the Anthocyanin pigment/flavonoid molecules, this leads to more red and purple leaves.” Emily Clawson said, “I had no idea that there was so much science behind the leaves changing and falling off the trees.” This is just a little part of all the science that goes into the fall season.