What phenomenon is described by the presence of 'holes' in the ozone layer?

The phenomenon characterized by 'holes' in the ozone layer is known as ozone depletion. This process involves the thinning of the ozone layer, primarily due to human-made chemicals such as chlorofluorocarbons (CFCs), halons, and other ozone-depleting substances.

When these substances are released into the atmosphere, they eventually reach the stratosphere, where ultraviolet (UV) radiation from the sun breaks them down, releasing chlorine atoms. These chlorine atoms can then react with ozone (O3) molecules, causing the ozone to break apart into oxygen molecules (O2) and reduce the overall concentration of ozone in the stratosphere. The result is a diminished ozone layer, which leads to increased levels of harmful UV radiation reaching the Earth's surface. This can have serious implications for environmental and human health, including higher rates of skin cancer and harm to ecosystems.

In contrast, global warming refers to the increase in average global temperatures due to the accumulation of greenhouse gases in the atmosphere. The greenhouse effect is a related but distinct phenomenon, where certain gases trap heat in the atmosphere, contributing to warming. Acid rain formation involves the precipitation of acidic components that result from pollution, particularly sulfur dioxide and nitrogen oxides, and is not directly