Which factor contributes to the formation of the ozone hole over Antarctica?

The formation of the ozone hole over Antarctica is primarily influenced by cold temperatures in the stratosphere that allow for the formation of polar stratospheric clouds (PSCs). These clouds form in the extremely low temperatures of the Antarctic winter and play a crucial role in the chemical processes that lead to ozone depletion.

During the Antarctic winter, the polar stratosphere becomes extremely cold, enabling the formation of PSCs. These clouds provide a surface for chemical reactions involving chlorine compounds, particularly those released from man-made substances like chlorofluorocarbons (CFCs). When sunlight returns in the spring, it triggers reactions on the surface of the PSCs, releasing chlorine atoms which subsequently catalyze the breakdown of ozone molecules in the atmosphere. This results in the thinning of the ozone layer, commonly referred to as the ozone hole.

Other factors like increased sunlight in summer, warm ocean currents, and high levels of carbon dioxide do not contribute to the formation of the ozone hole in the same way. Sunlight is critical for the chemical reactions but is pertinent only after the conditions for PSC formation have been established; warm currents do not promote the necessary cold temperatures in the stratosphere; and while carbon dioxide contributes to climate change, it does not directly