Final answer:
Chlorofluorocarbons (CFCs) have been responsible for the depletion of the ozone layer by breaking down ozone molecules in the stratosphere, creating an 'ozone hole' that increases harmful UV radiation exposure. The Montreal Protocol, an international agreement, has significantly reduced the production of CFCs, aiding in the recovery of the ozone layer. Continuous global efforts are aimed at further protecting and restoring the ozone layer.
Step-by-step explanation:
Ozone Layer Depletion by Chlorofluorocarbons (CFCs)
The depletion of the ozone layer is a critical environmental issue that has been largely attributed to human activity, particularly the emission of chlorofluorocarbons (CFCs). These chemicals, once widely used as refrigerants, have been shown to break down ozone molecules in the stratosphere, leading to the formation of an 'ozone hole,' predominantly over the southern hemisphere. This hole is largest during the spring months and allows for an increased amount of harmful ultraviolet (UV) radiation to reach Earth's surface, which can cause health problems such as skin cancer.
The impact of CFCs on the ozone layer was first highlighted in the scientific community by the groundbreaking work of scientists Molina and Rowland in 1974. Their research was pivotal in generating global attention and eventually led to the Montreal Protocol in 1987. This international treaty has helped phase out the production of ozone-depleting substances, including CFCs, and represents a successful example of worldwide cooperation in addressing a significant environmental challenge.
Despite the reduction in the use of CFCs, the legacy of their impact persists. Ozone concentrations in the upper atmosphere have been monitored and continuous efforts are in place globally to ensure further protection and eventual restoration of the ozone layer. The cooperation and regulatory actions stemming from the awareness of this issue have significantly contributed to a decline in the release of ozone-depleting chemicals.