Where is the ozone layer primarily located?

The ozone layer is primarily located in the stratosphere, which is the second layer of Earth's atmosphere, situated above the troposphere and below the mesosphere. This layer contains a high concentration of ozone (O3), which absorbs the majority of the sun's harmful ultraviolet (UV) radiation. The presence of ozone in the stratosphere plays a critical role in protecting living organisms on Earth by filtering out these harmful rays, which can cause skin cancer, cataracts, and other health issues, as well as impact ecosystems.

In contrast, the troposphere is where most of our weather occurs and contains a relatively low concentration of ozone, which is primarily a pollutant at ground level. The mesosphere and thermosphere are located above the stratosphere, with the mesosphere being involved in meteoric phenomena and the thermosphere extending into the region where the atmosphere becomes very thin. Neither of these layers is where the protective ozone layer is concentrated. Thus, the stratosphere is the correct answer, as it is specifically known for being the layer that contains the ozone layer essential for life on Earth.