Climbing a Tower

This afternoon we climbed to the top of a 120 foot tower. At the top, scientific instruments measure rainfall, light, carbon dioxide levels, wind, and how clear the air is. We were higher than the trees. The tower shook a little when the wind blew, but it wasn't bad. Above is a picture of a solar panel with spikey plastic pieces on top of it. What do you think the purpose of the plastic pieces is?