What is the primary function of the ozone layer?

The primary function of the ozone layer is to block harmful ultraviolet (UV) radiation from the sun. The ozone layer is a region of Earth's stratosphere that contains a high concentration of ozone (O₃) molecules. This layer absorbs the majority of the sun's harmful UV radiation, particularly UV-B and UV-C rays, which can cause skin cancer, cataracts, and other serious health issues in living organisms, as well as adversely affect ecosystems.

In contrast, while the ozone layer does play a role in regulating climate and temperature by allowing some sunlight to reach the Earth's surface, its most critical function is protecting life from UV damage. Producing oxygen primarily occurs through the process of photosynthesis in green plants and phytoplankton, not directly by the ozone layer itself. Additionally, weather patterns are influenced by the atmosphere as a whole rather than just the presence or absence of the ozone layer. Thus, blocking harmful UV radiation is the ozone layer's essential and defining role.