Final answer:
The ozone hole does not typically form over the Arctic due to less severe conditions compared to Antarctica, including warmer temperatures, fewer polar stratospheric clouds, and a less isolated polar vortex which allows for air mixing that can reduce ozone depletion.
Step-by-step explanation:
The question asks why an ozone hole does not typically form over the Arctic similar to the one over Antarctica. The ozone hole in the upper atmosphere, which involves a significant depletion of stratospheric ozone, has particularly been observed over Antarctica. This phenomenon owes its occurrence to a combination of extreme cold temperatures, the presence of polar stratospheric clouds (PSCs), and the isolation caused by a polar vortex. As spring arrives in Antarctica, PSCs melt and release halogenated compounds which, under the influence of sunlight, form radicals that catalytically destroy ozone molecules. The polar vortex over Antarctica prevents these halogens from being diluted, exacerbating ozone depletion locally and the development of the ozone hole.
While the Arctic does experience some ozone depletion, conditions are not as consistently severe as in Antarctica. Arctic winters are not as cold, and therefore PSCs are not formed as reliably. Also, the polar vortex is not as stable or as isolated as the one over Antarctica, allowing for some mixing with mid-latitude air that can moderate the depletion process. Due to these differences, an Arctic ozone hole like the one over Antarctica is less common.