Ozone depletion consequence – UGC NET Question

The stratospheric ozone layer acts as a protective shield that absorbs most harmful ultraviolet-B radiation from the sun. When this layer is depleted by chemicals like chlorofluorocarbons, more UV-B reaches the Earth’s surface. This leads to increased risks of skin cancer, cataracts, immune suppression in humans and damage to crops and marine ecosystems. Therefore, the primary environmental problem associated with ozone depletion is enhanced UV-B radiation, as stated in option A.

Option A:
Option A correctly links ozone depletion with increased UV-B radiation and the associated health and ecological impacts. It reflects scientific findings that ozone holes allow more biologically harmful radiation to pass through the atmosphere. This option aligns with the way the issue is presented in environmental studies and UGC NET materials.

Option B:
Option B is incorrect because the ozone layer has little effect on visible light, which largely passes through the atmosphere regardless of ozone concentration. Changes in ozone do not significantly alter visible light levels at the surface.

Option C:
Option C is incorrect since ozone depletion is not directly related to greenhouse gas concentrations. In fact, some ozone-depleting substances are also greenhouse gases, so their reduction may slightly reduce warming, but that is not the primary effect.

Option D:
Option D is incorrect because acid rain is mainly caused by sulphur dioxide and nitrogen oxides reacting with water vapour, not by stratospheric ozone depletion. The two phenomena are distinct atmospheric problems.