What is the primary purpose of the ozone layer?

The primary purpose of the ozone layer is to absorb harmful ultraviolet (UV) radiation from the sun. This protective layer is situated in the stratosphere, at an altitude of about 10 to 30 miles above the Earth's surface, and contains a high concentration of ozone (O3) molecules. By absorbing the majority of the sun's damaging UV radiation, the ozone layer plays a crucial role in protecting living organisms, including humans, from skin cancer, cataracts, and other health issues related to exposure to UV rays. It also helps to preserve ecosystems by protecting phytoplankton in the oceans and maintaining biodiversity on land.

While other functions, such as regulating climate and providing oxygen, are important aspects of Earth's atmosphere, they are not the primary role of the ozone layer. The layer does not significantly block visible light, nor is it a direct source of oxygen, as oxygen is predominantly produced through photosynthesis by plants and other organisms. Thus, the specific role of the ozone layer in absorbing UV radiation is vital for the health of the planet and its inhabitants.