Ozone concentrations measured over New Zealand are not affected directly by the ozone hole, which lies over Antarctica each spring. The ozone hole is an area where the ozone layer is less than 220 DU, caused mostly by ozone-depleting substances emitted by people.
The ozone layer over New Zealand is thinner.
Unfortunately, due to decades of man-made gas emissions, the ozone layer over New Zealand has continuously thinned. The ozone layer is like the Earth's personal sun protectant. The ozone layer's role is to absorb the harmful UV rays that are sent from the sun.
The culprit is human-made chlorofluorocarbons, or CFCs, which have risen to the stratosphere. Ultraviolet rays break up the CFCs, releasing chlorine, which destroys ozone. The resulting hole exposes life on Earth to harmful ultraviolet rays. CFCs were banned in 1996, but their lifetime is around 50 to 100 years.
This area is equivalent to almost seven times the territory of the EU. In late September 2022, the Antarctic ozone hole reached its maximum area of 24.5 million km². Up until early November 2022, the Antarctic ozone hole has been similarly large and long-lasting to the ones recorded in 2021 and 2020.
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).
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).
After the ozone hole discovery, heavy investment in scientific research, marshalling of economic resources and coordinated international political action helped to turn things around. In 1987, the Montreal Protocol was adopted to protect the ozone layer by phasing out the chemicals which deplete it.
The ozone hole is the region over Antarctica with total ozone of 220 Dobson Units or lower. This map shows the ozone hole on October 4, 2004. The data were acquired by the Ozone Monitoring Instrument on NASA's Aura satellite.
The long-lamented hole in the ozone layer is slowly mending itself, thanks to the success of an international agreement that banned chemicals that eat away at it, according to a new report from the United Nations (U.N.).
The hole still exists but scientists project the ozone layer to return to a condition not seen since before 1980 by about 2050.
First, Earth's elliptical orbit means it is closest to the sun in the New Zealand summer months of December and January. Second, New Zealand's relatively clean air means UV radiation is less likely to be scattered by airborne-pollution and more UV radiation reaches the ground.
While experts say the hole in the ozone is on track to be completely recovered by 2040 across most of the world and will fully bounce back by 2045 over the Arctic and by 2066 over the Antarctic - this doesn't mean New Zealanders should forget their hats or ditch the sunblock.
The ozone layer over southern Canada has thinned by an average of about 7% since the 1980s. In the late 1990s, average ozone depletion in the summer over Canada was between 3% and 7%. Ozone depletion in Canada is usually greatest in the late winter and early spring.
Ozone concentrations measured over New Zealand are not affected directly by the ozone hole, which lies over Antarctica each spring.
The ozone hole over Antarctica is usually more pronounced on the South American side of the frozen continent.
The ozone layer is the thinnest over Antarctica. This region is referred to as the "hole" in the ozone layer.
If current policies remain in place, the ozone layer is expected to recover to 1980 values (before the appearance of the ozone hole) by around 2066 over the Antarctic, by 2045 over the Arctic and by 2040 for the rest of the world.
A big reason we can't make more ozone to send into the upper atmosphere is because it would take a LOT of energy. In the atmosphere, this huge amount of energy comes from the sun. We also don't have a way to transport the ozone to the right places in the atmosphere.
The extra carbon would likely warm the world by anywhere from 0.5 to 1 C by the end of the century, most likely around 0.8 C, the scientists estimate. That's on top of a likely 1.7 C of extra warming just from the greenhouse effect of CFCs in the atmosphere.
As the ozone hole over Antarctica has in some instances grown so large as to affect parts of Australia, New Zealand, Chile, Argentina, and South Africa, environmentalists have been concerned that the increase in surface UV could be significant.
Scientists said the recovery is gradual and will take many years. If current policies remain in place, the ozone layer is expected to recover to 1980 levels — before the appearance of the ozone hole — by 2040, the report said, and will return to normal in the Arctic by 2045.
But overall, we see it decreasing through the past two decades. The elimination of ozone-depleting substances through the Montreal Protocol is shrinking the hole.” This map shows the size and shape of the ozone hole over the South Pole on Oct. 5, 2022, when it reached its single-day maximum extent for the year.
This 2022 the ozone hole closed roughly mid December while . the longest-lasting on record in 2020 closed on 28 December. In order to put the size of the last three ozone holes into perspective, we have considered the average ozone hole area between 7 September and 13 October since 1979.
The recovery of the ozone layer has been made possible by the successful elimination of some harmful industrial chemicals, together referred to as Ozone Depleting Substances or ODSs, through the implementation of the 1989 Montreal Protocol.
Healing the ozone and preventing an increase in UV radiation has averted substantial global warming to date, scientists say, a benefit that could extend to 2.5 degrees by end of century. That has given humanity a chance to limit overall warming below 1.5 degrees, a crucial threshold in keeping the planet hospitable.