Glossary
Atmospheric Layers
Distinct regions of the Earth's atmosphere, characterized by differences in temperature and density.
Example:
The atmospheric layers include the troposphere where weather occurs and the stratosphere where the ozone layer resides.
Chlorine Atom (Cl)
A highly reactive atom released from CFCs by UV radiation in the stratosphere. It acts as a catalyst in the destruction of ozone molecules.
Example:
A single chlorine atom (Cl) can destroy thousands of ozone molecules before it is eventually removed from the stratosphere.
Chlorine Monoxide (ClO)
A molecule formed when a chlorine atom reacts with an ozone molecule during ozone depletion. It then reacts with another ozone molecule, releasing the chlorine atom to continue the destructive cycle.
Example:
The formation of chlorine monoxide (ClO) is a key intermediate step in the catalytic destruction of stratospheric ozone by CFCs.
Chlorofluorocarbons (CFCs)
Man-made organic compounds containing carbon, chlorine, and fluorine atoms. They were widely used as refrigerants and propellants but are potent ozone-depleting substances.
Example:
The widespread use of chlorofluorocarbons (CFCs) in older refrigerators contributed significantly to ozone layer damage before they were phased out.
Montreal Protocol
An international treaty designed to protect the ozone layer by phasing out the production of numerous substances responsible for ozone depletion, such as CFCs.
Example:
The success of the Montreal Protocol is often cited as a prime example of effective international environmental cooperation.
Natural Ozone Cycle
The continuous process in the stratosphere where ozone molecules are naturally created from oxygen and destroyed by UV radiation, maintaining a dynamic equilibrium.
Example:
The natural ozone cycle ensures a steady concentration of ozone in the stratosphere, protecting Earth from harmful UV rays.
Ozone (O3)
A molecule consisting of three oxygen atoms. In the stratosphere, it forms the ozone layer, while at ground level, it is a harmful air pollutant.
Example:
The ozone (O3) molecule is constantly being formed and broken down in the stratosphere as part of a natural cycle.
Ozone Depletion
The thinning of the ozone layer in the stratosphere, primarily caused by the release of human-made chemicals like chlorofluorocarbons (CFCs).
Example:
Scientists observed significant ozone depletion over Antarctica, leading to the formation of the 'ozone hole.'
Ozone Layer
A region within the stratosphere containing a high concentration of ozone (O3) molecules. It plays a crucial role in absorbing harmful ultraviolet (UV) radiation from the sun.
Example:
Without the protective ozone layer, life on Earth would be exposed to dangerous levels of UV radiation, leading to increased skin cancer rates.
Stratosphere
The atmospheric layer located above the troposphere, extending from about 10 km to 50 km above Earth's surface. It is where the ozone layer is found.
Example:
Airplanes often fly in the lower stratosphere to avoid turbulence and benefit from smoother air.
Ultraviolet (UV) Radiation
A form of electromagnetic radiation emitted by the sun that has shorter wavelengths than visible light. High levels of UV radiation are harmful to living organisms.
Example:
Excessive exposure to ultraviolet (UV) radiation can cause sunburn and increase the risk of skin cancer.