Scientists say the ozone hole over Earth's South Pole now covers about 20 million square kilometers, or roughly three times the size of the United States, but they also point to positive advances in global environmental recovery efforts.
Maximum Extent
Newsweek magazine reported that on September 28, the ozone hole reached its largest extent of 22.4 million square kilometers, a relatively small area compared to historical measurements, according to researchers.
The ozone layer protects the Earth from dangerous UV radiation, but large holes in the barrier allow for increased exposure, which can lead to a higher incidence of skin cancer, lower crop yields, and damage to delicate ecosystems.
The hole this year is the seventh-smallest of its kind since the recovery began in 1992 with the implementation of the Montreal Protocol, an international accord to phase out ozone-depleting substances.
The Smallest Hole
"The Antarctic hole in 2024 is smaller than the ozone holes seen in the early 2000s," Paul Newman, the Chief Scientist for Earth Sciences at NASA's Goddard Space Flight Center in the Earth Sciences Division, stated.
"The gradual improvement over the past two decades shows that international efforts to curb ozone-destroying chemicals are paying off," Newman said.
The present reduction in the size of the ozone hole is attributable to lower levels of chlorofluorocarbons and fewer unexpected ozone leaks from the North Antarctic air current.
Signed in 1987, the Montreal Protocol commits countries worldwide to replacing hazardous chemicals with environmentally appropriate alternatives by 2010.
By the mid-1980s, the ozone layer had thinned dramatically, with broad portions of the Antarctic stratosphere nearly ozone-free by early October each year.
Major Sources
Ozone-depleting Refrigerants in refrigerators and air conditioners, as well as aerosols in hairspray, antiperspirants, and spray paint, are the main sources of CFC emissions.
Furthermore, the production of insulating foams and some industrial fire suppression systems emits these hazardous compounds into the environment.
Stephen Montzka of the National Oceanic and Atmospheric Administration's Global Monitoring Laboratory noted in a statement that while the 2024 data are positive, "the ozone layer is still far from fully recovered."
Researchers continue to monitor the ozone layer with better instrumentation, and weather balloons sent from the South Pole Atmospheric Research Observatory (ARO) provide further data, including a record low of 109 Dobson units on October 5.
The Dobson Unit is the most often used unit for measuring ozone levels. One Dobson Unit is the number of ozone molecules necessary to form a 0.01 millimeter thick layer of pure ozone at 0 degrees Celsius and 1 atmosphere of pressure (the air pressure at the Earth's surface).
Scientists predict that if current trends continue, the ozone layer will fully recover by 2066, marking a significant milestone in international environmental cooperation and scientific advancement.
