Globally, the total column average is about 300 Dobson Units. On Oct. 3, 2022, scientists recorded a lowest total-column ozone value of 101 Dobson Units over the South Pole. At that time, ozone was almost completely absent at altitudes between 14 and 21 kilometers (8 and 13 miles)—a pattern very similar to last year.
In the final quarter of 2022, scientists from NASA and the National Oceanic and Atmospheric Administration (NOAA), reported that the hole in the ozone layer is continuing to shrink. The hole lies above Antarctica and between 7 September and 13 October, 2022, it spanned an average area of 23.2 million square kilometres.
In 2022, the maximum ozone hole area of nearly 25 million km2 is reached slightly later than the average and it persists consistently with a large area until December.
Answer and Explanation: There is only one hole in the ozone layer at any given time. This hole forms during the coldest months of late winter when temperatures are low enough... See full answer below.
The hole still exists but scientists project the ozone layer to return to a condition not seen since before 1980 by about 2050.
The stratospheric ozone layer absorbs the biologically damaging wavelengths of ultraviolet (UV) rays but in the 1970s, Australia's ozone layer was severely thinned as a consequence of heavy use of ozone-depleting, substances such as chloroflurocarbons (CFCs) and hydro-chloroflurocarbons (HCFCs).
Australia has some of the highest levels of UV radiation in the world – in fact, UV radiation is strong enough to cause sunburn in as little as 11 minutes on a fine summer day. UV radiation from the sun is also one of the best natural sources for vitamin D so a balance is important.
The hole in the ozone layer — the portion of the stratosphere that protects our planet from the sun's ultraviolet rays — is continuing to decrease. The hole over Antarctica had an average area of 8.91 million square miles (23.2 million square kilometers).
Earth's ozone layer protects all life on Earth from the sun's harmful radiation.
Today, the ozone layer is healing, shielding the planet from the potentially devastating effects of ultraviolet radiation.
As levels of these manufactured chemicals have decreased in the last 14 years, the ozone hole has seen a slight improvement. Today, satellite observations by NASA and NOAA show the peak size of this year's ozone hole measured 9.3 million square miles—an area roughly the size of North America.
But there's evidence it's starting to disappear – and recover more or less as expected, says Solomon. Based on scientific assessments, the ozone layer is expected to return to pre-1980 levels around the middle of the century. Healing is slow because of the long lifespan of ozone-depleting molecules.
Chlorine and bromine chemicals high in the atmosphere eat at Earth's protective ozone layer. Cold weather creates clouds that release the chemicals, Newman said. More cold means more clouds and a bigger ozone hole.
Life couldn't exist without this protective ozone, which is also called the “ozone layer.” The sun gives off light, heat, and other types of radiation. Too much UV (ultraviolet) radiation can cause skin cancer, cataracts, and harm plants and animals.
Will the ozone layer recover? The ozone layer is expected to return to normal levels by about 2050. But, it is very important that the world comply with the Montreal Protocol; delays in ending production and use of ozone-depleting substances could cause additional damage to the ozone layer and prolong its recovery.
The ozone layer contains less than 10 parts per million of ozone, while the average ozone concentration in Earth's atmosphere as a whole is about 0.3 parts per million.
To halt the depletion of the ozone layer, countries around the world agreed to stop using ozone-depleting substances. This agreement was formalised in the Vienna Convention for the Protection of the Ozone Layer in 1985 and the Montreal Protocol on Substances that Deplete the Ozone Layer in 1987.
The deepest ozone hole occurred in 1994, when concentrations fell to just 73 DU on September 30.
It closed on 23 December, the third latest date after 1999 and 2020. The extent and longevity of the 2021 ozone hole can be explained by very cold temperatures in the stratosphere and a very stable polar vortex. This video shows the evolution of the 2021 Antarctic ozone hole.
Australia's unusually harsh sunshine results mainly from its location in the Southern Hemisphere. The elliptical orbit of the Earth places the Southern Hemisphere closer to the sun during its summer months than the Northern Hemisphere during its summer.
During summer, the Earth's orbit brings Australia closer to the sun (as compared to Europe during its summer), resulting in an additional 7% solar UV intensity. Coupled with our clearer atmospheric conditions, this means that Australians are exposed to up to 15% more UV than Europeans.
UV problem of another kind
"Tasmania is unique with the fact that in summer it gets to extreme level, and in winter it doesn't even get to moderate," Mr Carr said. "A few places on the mainland get below 3 in winter, but Tasmania — the whole island — struggles to get to 2 or 2.5, even on a sunny day."
Answer and Explanation: There is no hole in the ozone layer above Australia. However, there is a hole that develops in late winter over Antarctica, a nearby continent.
Countries that are affected by it the most are Argentina, Chile, South Africa, New Zealand and Australia. The largest ozone hole ever observed in the Antarctic was reported by NASA in September 2000. The hole spread out over 28.3 million square miles, more than three times larger than the United States.
Ozone depletion has been most severe over Antarctica because it provides the unique temperature and chemical conditions for effective ozone destruction by halogen gases.