Which layer of the atmosphere contains the ozone layer?

The stratosphere is the layer of the atmosphere that contains the ozone layer, which is crucial for blocking harmful ultraviolet (UV) radiation from the sun. This layer is located approximately 10 to 30 kilometers above the Earth's surface. The ozone layer absorbs most of the sun's harmful UV radiation, protecting living organisms, including humans, from its damaging effects, which can lead to skin cancer and other health issues, as well as adversely impacting plant life and ecosystems.

In contrast, the troposphere is the lowest layer of the atmosphere where weather occurs and contains most of the atmosphere's mass, but it does not have significant concentrations of ozone. The mesosphere, above the stratosphere, is where temperatures begin to decrease with altitude, and while it does contain some ozone, it is not where the bulk of the ozone layer is situated. The thermosphere, the uppermost layer, has very thin air, and while it contains ionized gases and is involved in phenomena like the auroras, it also does not contain the ozone layer. Therefore, the stratosphere is correctly identified as the layer that houses the ozone layer, contributing to essential atmospheric protective functions.