Depletion of the Ozone Layer: Its causes, effects, and possible solutions

The depletion of the ozone layer is a major concern today. The ozone layer protects us from the harmful rays of the sun; therefore it is imperative that we preserve it. Since more pollutants are produced today than ever before (because of the major increase in the population), there is a major concern that we create less pollutants to help conserve the ozone layer. In this research paper I will give vital information on how pollution affects the ozone layer and methods instituted to help the ozone layer. In this research paper you will also find out what the ozone layer actually is and the parts that it is composed of. The Earth’s atmosphere is divided into several layers. The lowest region, the troposphere, extends from the earth’s surface up to about 10 kilometers in altitude. All human activities take place in the troposphere. The next layer, the stratosphere, continues from 10 to 50 kilometers. Most commercial airline traffic occurs in the power part of the stratosphere. Most atmospheric ozone is concentrated in a layer in the stratosphere, about 15 to 30 kilometers above the Earth’s surface. Ozone is a molecule containing three oxygen atoms. It is blue in color and has a strong odor.

Normal oxygen, which we breathe has two oxygen atoms and is odorless. Ozone is much less common than normal oxygen. The ozone layer absorbs a portion of the radiation from the sun, preventing it from reaching the planet’s surface. Most importantly, it absorbs the portion of ultraviolet light called UVB. UVB has been linked to many harmful effects including various types of skin cancer, cataracts, and harm to some crops, certain materials, and some forms of marine life. At any given time, ozone molecules are constantly formed and destroyed in the stratosphere. The total amount, however, remains relatively stable. The concentration of the ozone layer can be thought of as a stream’s depth at a particular location. While ozone concentrations vary naturally with sunspots, the seasons, and latitude, these process are well understood and predictable. Records have been established spanning several decades that detail normal ozone levels during these natural cycles. Each natural reduction in ozone levels is followed by a recovery. Recently, however, convincing scientific evidence has shown that the ozone layer shield is being depleted well beyond changes due to natural processes.

Thinning of the ozone layer has been caused by a variety of ozone destroying chemicals released by human activities. More than half the damage has been caused by chlorofluorocarbons. For over 50 years, chlorofluorocarbons,(CFCs), were thought of as miracle substances. They are stable, nonflammable, low in toxicity, and inexpensive to produce. Over time, CFCs found uses as refrigerants, solvents, foam blowing agents, and in smaller applications. CFCs and other compounds have atmospheric life times long enough to allow them to be transported by winds into the stratosphere. Because they release chlorine and bromine when they breakdown, they damage the protective ozone layer. In the early 1970’s, researchers began to investigate the effects of various chemicals on the ozone layer, particularly CFCs, which contain chlorine. Potential impacts of other chlorine sources were examined also. Chlorine from pools, for example, do not reach the stratosphere. Those chlorine compounds readily combine with water and repeated measurements show that they rain out of the troposphere very quickly. In contrast, CFCs are so stable that they do not dissolve in rain.

There are no natural processes that will remove the CFCs from the lower atmosphere. Over time, the CFCs are driven into the stratosphere by winds. It typically takes seven to ten years for CFC molecules to rise through the lower atmosphere and reach the stratosphere.. The CFCs are stable that only exposure to strong UV radiation can break them down. When that happens, the CFC molecule releases atomic chlorine. One chlorine molecule can destroy over 100,000 ozone molecules. Some two billion pounds of CFCs are manufactured every year. Gaseous emissions of CFCs, both during manufacturing processes and later, from finished products have caused atmospheric levels of chlorine to dramatically increase. Scientists estimate that before 1900 chlorine comprised 0.6 parts per billion (pp.) of the stratosphere. Today, the chlorine level is about 3.5 pp., and growing by more than 1.0 pp. per decade. The net effect is to destroy ozone faster than it is naturally created. Scientists are finding that under this assault the protective ozone layer in the stratosphere is thinning.

In some regions it vanishes almost entirely for a few weeks every year. Although CFC use has been greatly reduced in recent years, CFC molecules already released in the lower atmosphere will be making their way into the stratosphere and further ozone depletion is expected. As a result, experts anticipate an increase in skin cancers, more cataracts, and reduced yields of some crops. The initial concern about the ozone layer in the 1970’s led to a ban on the use of CFCs as aerosol propellants in several countries, including the United States. However, production of CFCs and other ozone-depleting substances grew rapidly as new uses were discovered. Through the 1980’s, other uses expanded and the nations of the world became increasingly concerned that these chemicals would further harm the ozone layer. In 1985, the Vienna Convention was adopted to formalize international cooperation on this issue. Additional efforts were resulted in the signing of the Montreal Protocol in 1987. This was a treaty for the protection of the ozone layer.

A total ban on the use of CFCs during the 1990’s was proposed by the European Union. Hydrochlorofluorocarbons, or HCFCs, which cause less damage to the ozone layer than CFCs do are being used as substitutes for CFCs on a n interim basis in developed countries until 2020 and until 2016 in developing countries. To monitor ozone depletion on a global level in 1991, NASA launched the seven-ton Upper Atmosphere Research Satellite. Orbiting the Earth at an altitude of 372 miles. the spacecraft measures ozone variations at different altitudes and is providing the first complete pictures of upper level chemistry. Because of other measures taken, emissions of ozone-depleting substances are already falling. Assuming continued compliance, stratospheric chlorine levels will peak in a few years and then gradually return to normal. The good news is that the natural ozone production process will heal the ozone layer in about 50 years. In conclusion, much information was gained from my research paper. It told of how air pollution affects the ozone layer. The ozone layer is composed of two parts, the troposphere and the stratosphere. The ozone layer acts as a protective sunscreen to us by absorbing harmful UVB rays.

Ozone is a molecule that contains three oxygen atoms. Consistency of the ozone layer varies greatly from location to location. In some regions the layer disappears for weeks and then returns. This depletion of the ozone layer occurs because of the harsh reaction of CFCs on the atmosphere. CFCs were once used widely because they were thought of as an alternative because of their stability, resistance to fire, and low cost to be manufactured. Unknowingly, people were helping to deplete their sunscreen. Because CFCs are so stable, only presentation to harsh radiation could break them down. When CFCs are broken down they release atomic chlorine. Since one atomic chlorine molecule can destroy over 100,00 ozone molecules, the effect is that the ozone layer is being depleted faster than it can heal itself. Much research had gone into ways to help prevent depletion of the ozone layer. One method instituted was to ban the use of CFCs. Although this was incorporated, CFC molecules already located in the lower atmosphere will journey into the upper atmosphere and cause more depletion.

After this fact was discovered, many more methods were put to use. Many treaties were signed to help aid in finding ways to help treat the ozone layer. Hydrochlorofluorocarbons were put to use because they cause less damage to the ozone layer. NASA also helped in the effort by launching the seven-ton Upper Atmosphere Research Satellite into orbit in 1991. It measured ozone variations at different altitudes. Due to this and many other measures taken, the spread of many ozone depleting chemicals has been greatly reduced. Jason Doyle April 14,2000 The depletion of the ozone layer is a major concern today. The ozone layer protects us from the harmful rays of the sun; therefore it is imperative that we preserve it. Since more pollutants are produced today than ever before (because of the major increase in the population), there is a major concern that we create less pollutants to help conserve the ozone layer. In this research paper I will give vital information on how pollution affects the ozone layer and methods instituted to help the ozone layer.

In this research paper you will also find out what the ozone layer actually is and the parts that it is composed of. The Earth’s atmosphere is divided into several layers. The lowest region, the troposphere, extends from the earth’s surface up to about 10 kilometers in altitude. All human activities take place in the troposphere. The next layer, the stratosphere, continues from 10 to 50 kilometers. Most commercial airline traffic occurs in the power part of the stratosphere. Most atmospheric ozone is concentrated in a layer in the stratosphere, about 15 to 30 kilometers above the Earth’s surface. Ozone is a molecule containing three oxygen atoms. It is blue in color and has a strong odor. Normal oxygen, which we breathe has two oxygen atoms and is odorless. Ozone is much less common than normal oxygen. The ozone layer absorbs a portion of the radiation from the sun, preventing it from reaching the planet’s surface.

Most importantly, it absorbs the portion of ultraviolet light called UVB. UVB has been linked to many harmful effects including various types of skin cancer, cataracts, and harm to some crops, certain materials, and some forms of marine life. At any given time, ozone molecules are constantly formed and destroyed in the stratosphere. The total amount, however, remains relatively stable. The concentration of the ozone layer can be thought of as a stream’s depth at a particular location. While ozone concentrations vary naturally with sunspots, the seasons, and latitude, these process are well understood and predictable. Records have been established spanning several decades that detail normal ozone levels during these natural cycles. Each natural reduction in ozone levels is followed by a recovery. Recently, however, convincing scientific evidence has shown that the ozone layer shield is being depleted well beyond changes due to natural processes. Thinning of the ozone layer has been caused by a variety of ozone destroying chemicals released by human activities. More than half the damage has been caused by chlorofluorocarbons.

For over 50 years, chlorofluorocarbons,(CFCs), were thought of as miracle substances. They are stable, nonflammable, low in toxicity, and inexpensive to produce. Over time, CFCs found uses as refrigerants, solvents, foam blowing agents, and in smaller applications. CFCs and other compounds have atmospheric life times long enough to allow them to be transported by winds into the stratosphere. Because they release chlorine and bromine when they breakdown, they damage the protective ozone layer. In the early 1970’s, researchers began to investigate the effects of various chemicals on the ozone layer, particularly CFCs, which contain chlorine. Potential impacts of other chlorine sources were examined also. Chlorine from pools, for example, do not reach the stratosphere. Those chlorine compounds readily combine with water and repeated measurements show that they rain out of the troposphere very quickly. In contrast, CFCs are so stable that they do not dissolve in rain. There are no natural processes that will remove the CFCs from the lower atmosphere.

Over time, the CFCs are driven into the stratosphere by winds. It typically takes seven to ten years for CFC molecules to rise through the lower atmosphere and reach the stratosphere.. The CFCs are stable that only exposure to strong UV radiation can break them down. When that happens, the CFC molecule releases atomic chlorine. One chlorine molecule can destroy over 100,000 ozone molecules. Some two billion pounds of CFCs are manufactured every year. Gaseous emissions of CFCs, both during manufacturing processes and later, from finished products have caused atmospheric levels of chlorine to dramatically increase. Scientists estimate that before 1900 chlorine comprised 0.6 parts per billion (pp.) of the stratosphere. Today, the chlorine level is about 3.5 pp., and growing by more than 1.0 pp. per decade. The net effect is to destroy ozone faster than it is naturally created. Scientists are finding that under this assault the protective ozone layer in the stratosphere is thinning. In some regions it vanishes almost entirely for a few weeks every year.

Although CFC use has been greatly reduced in recent years, CFC molecules already released in the lower atmosphere will be making their way into the stratosphere and further ozone depletion is expected. As a result, experts anticipate an increase in skin cancers, more cataracts, and reduced yields of some crops. The initial concern about the ozone layer in the 1970’s led to a ban on the use of CFCs as aerosol propellants in several countries, including the United States. However, production of CFCs and other ozone-depleting substances grew rapidly as new uses were discovered. Through the 1980’s, other uses expanded and the nations of the world became increasingly concerned that these chemicals would further harm the ozone layer. In 1985, the Vienna Convention was adopted to formalize international cooperation on this issue. Additional efforts were resulted in the signing of the Montreal Protocol in 1987. This was a treaty for the protection of the ozone layer.

A total ban on the use of CFCs during the 1990’s was proposed by the European Union. Hydrochlorofluorocarbons, or HCFCs, which cause less damage to the ozone layer than CFCs do are being used as substitutes for CFCs on a n interim basis in developed countries until 2020 and until 2016 in developing countries. To monitor ozone depletion on a global level in 1991, NASA launched the seven-ton Upper Atmosphere Research Satellite. Orbiting the Earth at an altitude of 372 miles. the spacecraft measures ozone variations at different altitudes and is providing the first complete pictures of upper level chemistry. Because of other measures taken, emissions of ozone-depleting substances are already falling. Assuming continued compliance, stratospheric chlorine levels will peak in a few years and then gradually return to normal. The good news is that the natural ozone production process will heal the ozone layer in about 50 years. In conclusion, much information was gained from my research paper. It told of how air pollution affects the ozone layer. The ozone layer is composed of two parts, the troposphere and the stratosphere. The ozone layer acts as a protective sunscreen to us by absorbing harmful UVB rays.

Ozone is a molecule that contains three oxygen atoms. Consistency of the ozone layer varies greatly from location to location. In some regions the layer disappears for weeks and then returns. This depletion of the ozone layer occurs because of the harsh reaction of CFCs on the atmosphere. CFCs were once used widely because they were thought of as an alternative because of their stability, resistance to fire, and low cost to be manufactured. Unknowingly, people were helping to deplete their sunscreen. Because CFCs are so stable, only presentation to harsh radiation could break them down. When CFCs are broken down they release atomic chlorine. Since one atomic chlorine molecule can destroy over 100,00 ozone molecules, the effect is that the ozone layer is being depleted faster than it can heal itself. Much research had gone into ways to help prevent depletion of the ozone layer.

One method instituted was to ban the use of CFCs. Although this was incorporated, CFC molecules already located in the lower atmosphere will journey into the upper atmosphere and cause more depletion. After this fact was discovered, many more methods were put to use. Many treaties were signed to help aid in finding ways to help treat the ozone layer. Hydrochlorofluorocarbons were put to use because they cause less damage to the ozone layer. NASA also helped in the effort by launching the seven-ton Upper Atmosphere Research Satellite into orbit in 1991. It measured ozone variations at different altitudes. Due to this and many other measures taken, the spread of many ozone depleting chemicals has been greatly reduced.