Ozone Layer: This is a layer in the Earth's stratosphere containing a high concentration of ozone molecules. It absorbs most of the Sun's harmful ultraviolet radiation.
Greenhouse Gases: These are gases in Earth's atmosphere that trap heat. They let sunlight pass through the atmosphere, but they prevent the heat that the sunlight brings from leaving the atmosphere. The main greenhouse gases are water vapor, carbon dioxide, methane, nitrous oxide, and chlorofluorocarbons.
Stratospheric Ozone Depletion: This refers to the thinning of the ozone layer in upper layers of the atmosphere (stratosphere) due to its reaction with pollutants like CFCs which break down ozone molecules.