The 2018 Antarctic Ozone Hole Season Date: 17th December 2018.
This year’s Antarctic ozone hole has finally come to an end.
It was one of the largest holes of recent years.
The process that creates the Antarctic ozone hole begins around May, when the stratosphere cools as winter starts.
When was the ozone hole the biggest?
The largest single-day ozone hole recorded by satellite was 29.9 million square kilometers (11.5 million square miles) on September 9, 2000. The ozone “hole” is not literally a hole; rather, the phenomenon is defined as the area where the concentration of ozone drops below the historical threshold of 220 Dobson Units.
Where is the largest hole in the ozone layer located?
How much longer will the ozone layer last?
There is still a long way to go for a complete recovery. The hole’s peak last year measured at two and a half times the size of the U.S. CFCs can linger in the atmosphere for 50 to 100 years, according to Anne Douglass, co-author and atmospheric scientist at Goddard.
In which season ozone hole appears in Antarctica?
The ozone hole occurs during the Antarctic spring, from September to early December, as strong westerly winds start to circulate around the continent and create an atmospheric container. Within this polar vortex, over 50 percent of the lower stratospheric ozone is destroyed during the Antarctic spring.
How big is the hole in the ozone layer 2018?
Antarctic ozone today: The 2018 ozone hole has formed and ozone values continue to drop across the continent. The hole is currently above average size for the decade at 23 million square kilometres.
What would happen if the ozone layer disappeared?
The ozone layer is an important part of Earth’s atmosphere, shielding us from harmful ultraviolet (UV) radiation from the sun. But what would happen if the ozone layer gradually disappeared? About 30 years ago, atmospheric scientists predicted that this could happen—and that it was being caused by human activity.
Where is the ozone layer thickest?
The ozone layer is mainly found in the lower portion of the stratosphere, from approximately 15 to 35 kilometers (9.3 to 21.7 mi) above Earth, although its thickness varies seasonally and geographically. The ozone layer was discovered in 1913 by the French physicists Charles Fabry and Henri Buisson.
Can the ozone layer rebuild itself?
Ozone layer ‘shows signs of recovery’, say scientists. The Earth’s protective ozone layer is starting to repair itself, according to a panel of United Nations scientists. The main reason behind its recovery, they say, is the fact that certain chemicals, such as those used in aerosol cans, were phased out in the 1980s.
Is there a hole in the ozone layer over Australia?
Firstly, the ozone layer in the mid-latitude (e.g. over Australia) is thinned, leading to more UV radiation reaching the earth. Data collected in the upper atmosphere have shown that there has been a general thinning of the ozone layer over most of the globe.
Has the Montreal Protocol been a success story?
Climate Success Story: Saving the Ozone Layer. The Montreal Protocol, adopted in 1987, is showing success at removing ozone-depleting substances from the atmosphere, a NASA scientist says, with ozone levels projected to return to 1980 levels by 2032.
What year will the ozone layer be destroyed?
Production of ozone-depleting substances was finally halted in 1992, though their abundance is only beginning to decline because the chemicals can reside in the atmosphere for 50 to 100 years. The peak abundance of CFCs in the atmosphere occurred around 2000, and has decreased by roughly 4 percent to date.
When was the ozone hole discovered?
Why ozone hole is more in Antarctica?
The severe depletion of the Antarctic ozone layer known as the “ozone hole” occurs because of the special atmospheric and chemical conditions that exist there and nowhere else on the globe. The very low winter temperatures in the Antarctic stratosphere cause polar stratospheric clouds (PSCs) to form.
How long does the ozone hole last?
As the years have gone by the Ozone Hole has increased rapidly and is as large as the Antarctica continent. The hole lasts for only two months, but its timing could not be worse. Just as sunlight awakens activity in dormant plants and animals, it also delivers a dose of harmful ultraviolet radiation.
What happened to the ozone hole?
But in May 1985 scientists with the British Antarctic Survey shocked the world when they announced the discovery of a huge hole in the ozone layer over Antarctica. Technically a substantial thinning of the ozone layer, the ozone “hole” has been opening every spring since the 1970s, the scientists reported.
How big is the ozone hole now?
Last year, the ozone hole reached a maximum 8.9 million square miles, 2 million square miles less than in 2015. The average area of these daily ozone hole maximums observed since 1991 has been roughly 10 million square miles.
Is there still a hole in the ozone layer 2017?
What caused the ozone hole?
Ozone depletion occurs when chlorofluorocarbons (CFCs) and halons—gases formerly found in aerosol spray cans and refrigerants—are released into the atmosphere (see details below). CFCs and halons cause chemical reactions that break down ozone molecules, reducing ozone’s ultraviolet radiation-absorbing capacity.
What would happen if there was no mesosphere?
The air is still thin, so you wouldn’t be able to breathe up in the mesosphere. The meteors make it through the exosphere and thermosphere without much trouble because those layers don’t have much air. But when they hit the mesosphere, there are enough gases to cause friction and create heat.
What would life be like without the ozone layer?
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.
Why is the ozone layer disappearing a problem?
Because CFCs are so stable near the ground, it took decades before scientists started seeing signs of this ozone problem higher in the atmosphere. It wasn’t until the 1970s that chemists learned that CFCs break into chlorine atoms when exposed to intense UV light from the sun.
Why are skin cancer rates so high in Australia?
Australia has one of the highest rates of skin cancer in the world. Anyone can be at risk of developing skin cancer, though the risk increases as you get older. The majority of skin cancers in Australia are caused by exposure to UV radiation in sunlight.
Why does Australia have a hole in the ozone?
Stratospheric ozone does reduce the amount of UV reaching the Earth’s surface. So the depletion of the ozone layer caused legitimate concern and prompted the establishment of the “Montreal protocol” designed to eliminate ozone-damaging pollutants and repair the ozone hole.
Why is the ozone layer thinner in Australia?
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).
Photo in the article by “Flickr”