Final answer:
The hole in the ozone layer over Antarctica is formed due to unique atmospheric conditions and the presence of polar stratospheric clouds. These clouds trap chemicals that destroy ozone, and when sunlight returns in the spring, the chemicals are released and react with the ozone, leading to its depletion. This process results in the formation of the ozone hole.
Step-by-step explanation:
The ozone hole over Antarctica is formed by a slew of unique atmospheric conditions over the continent that combine to create an ideal environment for ozone destruction. One of the main factors contributing to the hole's existence is the presence of polar stratospheric clouds (PSCs) that form during the extremely cold winter months. These clouds trap chlorine and nitric acid in their ice crystals, which are then released and photolyzed by sunlight in the spring. As a result, as much as half of the lower stratospheric ozone can be destroyed, creating the ozone hole.