The hole in the ozone layer is primarily located over Antarctica. It is a region in the stratosphere above the Antarctic where total ozone concentration drops exceptionally low, below 220 Dobson Units, forming what is called an "ozone hole." This hole appears annually during the Southern Hemisphere spring, from about August to October, due to chemical reactions involving chlorine and bromine compounds from human-made CFCs and the extremely cold stratospheric conditions there. The hole is not an absence of ozone but a significant depletion compared to historical levels. The size and depth of this ozone hole can vary yearly with changes in temperature and stratospheric wind patterns near the South Pole.
Although the hole is mainly over Antarctica, it has been monitored using satellites, and its maximum size typically occurs between mid-September and mid-October each year. Efforts under the Montreal Protocol have led to a gradual recovery of the ozone layer, and the current trend shows the hole is slowly shrinking, with a potential full recovery expected around 2066.
In summary, the hole in the ozone layer is located above the Antarctic region in the Earth's stratosphere and is characterized by a significant seasonal depletion of ozone during the Southern Hemisphere spring.
