By: Rhea Agrawal
The Antarctic ozone hole, located near the South Pole, is the smallest it has ever been since it was primarily recorded in 1985, NASA said. The hole forms during late winter in the Southern Hemisphere when the Sun’s rays begin to deplete the layer.
The ozone layer can be found anywhere from seven to 25 miles above the Earth’s surface in the stratosphere. It acts as a sort of sunscreen because it protects Earth from harmful ultraviolet radiation that can cause skin cancer, cataracts, and other injuries to health. Although the size of the hole has been dwindling over the years, the smaller size this year is a result of atypical weather and wind patterns.
“It’s great news for ozone in the Southern Hemisphere,” explains Paul Newman, head scientist for Earth Sciences at NASA, in a report on the ozone layer that was released this week. “But it’s important to recognize that what we’re seeing this year is due to warmer stratospheric temperatures. It’s not a sign that atmospheric ozone is suddenly on a fast track to recovery.”
According to NASA, the ozone hole that sits on top of Antarctica typically expands to a maximum area of roughly eight million square miles in late September and early October, during regular weather patterns. However, in 2019, the hole only extended to a maximum of 6.3 million square miles on September 6, and then reduced to 3.9 million square miles and has stayed the same ever since.
This is not the first time that the weather has caused the hole to decrease in size. In fact, it is the third time in the past 40 years that ozone depletion has decreased significantly due to the same reasons. Smaller holes were also recorded in September of 1988 and 2002, explains Susan Strahan, an atmospheric scientist who works at NASA Goddard.
“It’s a rare event that we’re still trying to understand,” Dr. Strahan said.
When the Antarctic Ozone hole was initially discovered in 1985, scientists associated it with the use of man-made substances such as chlorofluorocarbons, often found in refrigerators and other cooling devices. In 1987, about 200 countries created an agreement to control how much of those substances were used, which allowed the hole to slowly recover. The layer is expected to go back to 1980s levels by 2070, NASA and NOAA say.
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