Humans have damaged the ozone layer by adding molecules containing chlorine or bromine that lead to ozone destruction. The largest group among these are chlorofluorocarbons (CFCs). At ground level, these molecules are stable and have many uses in industrial and domestic applications. However, when they are released into the atmosphere, they drift up to the stratosphere, pushed by winds and atmospheric mixing.

Ozone (O3) is a molecule made up of three oxygen atoms. The oxygen we breathe (O2) is similar but has only two oxygen atoms. High up in a region of the upper atmosphere known as the stratosphere, light rays can break down breathable oxygen into two individual oxygen atoms. Single oxygen atoms are quite reactive, and ozone is formed when one of these lone oxygens bump into and combine with O2. But ozone isn't very stable either.

Through extensive research, scientists identified the human-produced chemicals that are responsible for the destruction of stratospheric ozone. As evidence emerged on the extent of the threat to the ozone layer, the international community agreed to control ozone-depleting substances and schedule a timetable for completely phasing them out. This agreement is known as the Montreal Protocol and is a monumental achievement in international cooperation and environmental protection.

Global warming and ozone depletion are two separate but related threats. Global warming and the greenhouse effect refer to the warming of the lower part of the atmosphere (also known as the troposphere) due to increasing concentrations of heat-trapping gases. By contrast, the ozone hole refers to the loss of ozone in the upper part of the atmosphere, called the stratosphere.

Ozone is very rare in our atmosphere, averaging about three molecules of ozone for every 10 million air molecules. In spite of this small amount, ozone plays vital roles in the atmosphere. This document provides answers to some of the questions that are most frequently asked about ozone and the changes that have been occurring in recent years.

No, the amount of CFCs released from all medications is minimal. Historically, asthma aerosol inhalers have released less than 1% of the estimated half a million tonnes of CFCs released by all industries in Australia since the inception of asthma aerosol inhalers in the 1960s.

Contrary to what a lot of people think, none! 'Good' and 'bad' ozone exist (like good and bad cholesterol) but neither plays any part in global warming. The 'good' ozone is to be found 15 km above our heads in the famous ozone layer. This layer is permanent and protects us from harmful ultra violet rays emanating from the sun. The hole in the ozone is produced by chlorofluorocarbons (CFC), chloride gases which up until 1987 were used in aerosol cans and refrigerating systems.

Yes, some do while others do not. Normally all refrigerants handled by reputed manufacturers and its service technicians will never be released to the atmosphere that could deplete the ozone layer. It is important to note that refrigerants alone are not responsible as many other chemicals cause global warming problems apart from Ozone depletion. Burning of fossil fuels causes problems on larger scale.

Ozone's unique physical properties allow the ozone layer to act as our planet's sunscreen, providing an invisible filter to help protect all life forms from the sun's damaging ultraviolet (UV) rays. Most incoming UV radiation is absorbed by ozone and prevented from reaching the Earth's surface. Without the protective effect of ozone, life on Earth would not have evolved the way it has.

Global ozone levels declined an average of about 3 per cent between 1979 and 1991. This rate of decline is about three times faster than that recorded in the 1970's. In addition to Antarctica, ozone depletion now affects almost all of North America, Europe, Russia, Australia, New Zealand, and a sizable part of South America. Short term losses of ozone can be much greater than the long term average. In Canada, ozone depletion is usually greatest in the late winter and early spring.

The depletion of the ozone layer leads, on the average, to an increase in ground-level ultraviolet radiation, because ozone is an effective absorber of ultraviolet radiation. The Sun emits radiation over a wide range of energies, with about 2% in the form of high-energy, ultraviolet (UV) radiation. Some of this UV radiation (UV-B) is especially effective in causing damage to living beings, for example, sunburn, skin cancer, and eye damage to humans.

High up in the atmosphere, in a region called the stratosphere between 19 and 30 km above the Earth's surface, ozone is constantly being produced and destroyed naturally. This ozone layer filters out UV rays from the Sun and protects life on Earth. Usually there is a fine balance between the build up and loss of ozone.

Yes, significant depletion of the Arctic ozone layer now occurs in some years in the late winter/spring period (January-April). However, the maximum depletion is generally less severe than that observed in the Antarctic and is more variable from year to year. A large and recurrent “ozone hole,” as found in the Antarctic stratosphere, does not occur in the Arctic.

Scientists expect to detect the recovery of the ozone layer with careful comparisons of the latest ozone measurements with past values. Changes in total overhead ozone at various locations and in the extent and severity of the Antarctic “ozone hole” will be important factors in gauging ozone recovery. Natural variations in ozone amounts will limit how soon recovery can be detected with future ozone measurements.

Measuring the ozone at both poles is a 'barometer' of sorts. Though typically the ozone varies in densities and coverage at these areas, it also reflects the overall warming and depletion of the ozone worldwide. Sun shining on the poles is not filtered of harmful ultraviolet radiation due to the increasing lack of ozone.

Studies indicate that they in reality have only a minute impact, both in absolute terms and relative to other chemical sources. The remainder of this item is a response from the author of the quoted study, Charles Jackman. Industrial sources: 300,000,000 kilograms/year Natural sources: 75,000,000 kilograms/year Shuttle sources: 725,000 kilograms/year The shuttle source assumes 9 space shuttles and 6 Titan rockets are launched yearly. Thus the launches would add less than 0.

On the theory that chlorofluorocarbons put chlorine in the upper atmosphere which destroys ozone, their manufacture has been banned. A 90 percent reduction would have been just as effective and less economically disruptive, but industry seems to be adjusting to the total ban.

No. Because ozone reacts so quickly with contaminants in water and air, it converts back to oxygen within minutes or even seconds. Any ozone molecules that break free from the pool or spa water will convert to oxygen and never reach the atmosphere.

In 1987, the nations of the world banded together to draft the Montreal Protocol to phase out the production and use of CFCs. The 43 nations that signed the protocol agreed to freeze consumption and production of CFCs at 1986 levels by 1990, reduce them 20% by 1994, and reduce them another 30% by 1999. The alarming loss of ozone in Antarctica and worldwide continued into the 1990's, and additional amendments to further accelerate the CFC phase-out were adopted.

Sulfuryl fluoride, the active ingredient in ProFume, is not an ozone-depleting chemical. ProFume contains no chlorine or bromine and, thus, cannot react to deplete stratospheric ozone by the known mechanisms. It is fully oxidized and, thus, is not expected to interact or contribute to local ozone formation (such as smog). When a commodity or facility is aerated, ProFume rapidly dissipates to non-detectable levels. Dow AgroSciences was awarded the Stratospheric Ozone Protection Award by the U.S.

From time to time, people claim that chemicals released from some rockets, in particular NASA's Space Shuttle's Solid Rocket Boosters (SRBs), are responsible for a significant amount of damage to the ozone layer. Studies indicate that they have only a minute impact (less than seven-thousandths of one percent), both in absolute terms and relative to other chemical sources. It is much less than total ozone variability associated with volcanic activity and solar flares.

No. The amount of ozone above a location on the Earth varies naturally with latitude, season, and from day-to-day. Under normal circumstances, the ozone layer is thickest over the poles and thinnest around the equator. The ozone layer over Canada is normally thicker in winter and early spring; it can vary naturally by about 25 per cent between January and July. Weather conditions can also cause considerable daily variations.

The best strategy for ozone protection is to avoid purchasing products containing ozone-depleting substances. Ask before you purchase fire extinguishers, foam products, refrigerators and air conditioners. Refuse to purchase products containing ozone-depleting substances if alternatives are available. Write companies still using these chemicals and voice your concerns.

A very thin level of ozone surrounds the earth and serves as a filter against UV rays. The use of chlorofluorocarbons has influenced the depletion of the ozone layer, allowing increased amounts of shorter wavelengths of UV light to reach the earth's surface. Even though indoor tanning can help gradually build pigmentation (the body's own way of avoiding excessive exposure to UV light). with a depleting ozone layer, there are now more chances to overexpose your skin.