Ozone
Ozone is a form of oxygen that shields Earth from the sun but can harm plants near the ground.
A sheet of wax paper sits on top of a bowl of fruit. It blocks harsh sunlight from drying out the fruit below. But if that same wax paper fell to the counter, it would cover the food and trap moisture, causing mold. Ozone works the same way: helpful high up, harmful at ground level.
Explaining ozone by grade level
High up in the sky, a special kind of air blocks harsh rays from the sun. But near the ground, that same kind of air can hurt plants. When you grow plants in air with too much of it, they grow less. Clean air helps plants stay strong and tall.
Projects that explore ozone
Ozone is a form of oxygen that collects near the ground on certain days, contributing to poor air quality. When weather conditions trap pollutants close to the surface, ozone levels can spike. Tracking ozone alongside temperature, wind speed, and barometric pressure reveals which weather patterns line up with the worst pollution days.
While ozone high in the atmosphere shields Earth from harmful sunlight, ozone near the ground can damage living plants. Radish seedlings exposed to ozone gas grew to only 13.1 cm on average, compared to 19.7 cm for radishes in normal air. The ozone-exposed plants also germinated more slowly, and by the final week they began to shrivel and die.