The ozone layer helps to protect life from harmful ultraviolet radiation. Atmospheric concentrations of ozone vary naturally depending on. As a result, it is creating alarming situations like ozone layer depletion, global warming and acid rains sivasakthivel and siva kumar reddy, 2011. I often encounter college students who conflate two very distinct problems. Effects of ozone layer depletion on humans uvb the higher energy uv radiation absorbed by ozone is generally accepted to be a contributory factor to skin cancer. The latter phenomenon is referred to as the ozone hole. In addition, increased surface uv leads to increased tropospheric ozone, which is a health risk to humans. Forty years ago, scientists warned that a hole in the layer of ozone surrounding the earth could have serious effects on human health and the environment. The impact of ozone in the troposphere as a local air pollutant is instead covered in our. This problem is being solved thanks to a global agreement to stop the use of ozonedepleting chemicals that damage the ozone layer. A combination of low temperatures, elevated chlorine, and bromine concentrations in the upper stratosphere are responsible for the destruction of ozone. These gases still reside in some products which are liable to leakage over time. Ozone depletion and climate change environment canada. These radiations can cause severe diseases in humans such as skin cancer, eye.
The emission of ozonedepleting gases impacted the earths ozone layer a layer that. A close look at the evolution at the life on earth reveals that initially the. It is responsible for the survival of life on earth. Pdf causes of ozone layer depletion and its effects on. Layers of the atmospherethe atmosphere is divided into five layers. Twenty questions and answers about the ozone layer noaaesrl. Ozone is ozone is a form of oxygen with 3 oxygen atoms o3. Ozone depletion, gradual thinning of earth s ozone layer in the upper atmosphere caused by the release of chemical compounds containing gaseous chlorine or bromine from industry and other human activities.
Causes of ozone layer depletion and its effects on human. Project report on ozone depletion environmental pollution. Presence of ozone in the lower atmosphere is considered as a pollutant and a greenhouse gas. National research programme on global air pollution and climate change nrp. The production and emission of chlorofluorocarbons cfcs, is the leading cause of ozone layer depletion. Tropospheric ozone often termed bad ozone is manmade, a result of air pollution from internal combustion engines and power plants. Ozone is a triatomic form of oxygen o 3, found in the earths atmosphere. The world meteorological or ganization wmo, 1995 predicted that the depletion of the ozone layer peaked around 1998 and the layer would slowly recover by 2045 12. Causes and effects of ozone layer depletion that are. The increase in the levels of uv rays lead to high rate of skin cancer and eye related problems. Find out what caused the ozone hole, and how the 1989 montreal protocol sought to put an end to ozone depletion. Recognition of the harmful effects of cfcs and other ozonedepleting substances led to the montreal protocol on substances that deplete the ozone layer in 1987, a landmark agreement to phase out. However, near the surface where we live and breathe, ozone is a harmful pollutant that causes damage to lung tissue and plants.
The atmosphere acts like a multilayer shield that protects earth from dangerous solar radiation. Enhancement of the green house effect may also be causing. The layer closest to the earths surface is the troposphere. Although ozone o3 is present in small concentrations throughout the atmosphere, most ozone about 90% exists in the stratosphere, in a layer between 10 and 50 km above the surface. The latest ozone layer depletion news is included at the foot of the page.
Frequently asked questions about the ozone layer us epa. It can be found in small concentrations in the troposphere where it is considered a pollutant. The odp is the ratio of the impact on ozone of a chemical compared to the impact of a similar mass of cfc11. They help shield our planet from harmful solar radiation.
Predictions of significant increases in the incidence of skin cancer resulting from continued use of cfcs spurred international action. Which of the following statements about ozone is true. Ozone layer blocks around 97% of the total radiation received by the earth. The ozone layer lies approximately 1540 kilometers 1025 miles above the earths surface, in the stratosphere. Global warming is caused by the greenhouse effect, which is essential to life as we know it on planet earth. Ozone layer, region of the upper atmosphere, between roughly 15 and 35 km 9 and 22 miles above earths surface, containing relatively high concentrations of ozone molecules. The ozone layer depletion is a major concern and is associated with a number of factors. In 1987, 56 countries agreed under what became known as the montreal protocol to cut cfc production. Learn vocabulary, terms, and more with flashcards, games, and other study tools. But 10 to 30 miles above the earths surface 1648 km, ozone molecules protect life on earth. Ozone depletion, gradual thinning of earths ozone layer caused by the. Protecting the ozone layer while also preventing climate.
The ozone layer has historically protected the earth from the harmful uv rays, although in recent decades this protection has diminished due to stratospheric ozone depletion. But many researchers do not agree with these predictions,14 and express their. There are also springtime polar tropospheric ozone depletion. Here we will study polar vortex circumpolar vortex which is a polar cyclone. The ozone layer is a natural layer of gas in the upper atmosphere which protects humans and other living things from the harmful ultraviolet uv rays of the sun. Ozonedepleting substances ozone layer protection us epa. For each ods, this page provides the compounds atmospheric lifetime, ozone depletion potential ozone depletion potentiala number that refers to the amount of ozone depletion caused by a substance. Here, groundlevel or bad ozone is an air pollutant that is harmful to breathe and it damages crops, trees and other vegetation. However, because it occurs in such a low concentration, its vulnerable to ozonedepleting chemicals, such as cfcs. Protection of the ozone layer climate action european commission.
Ozone depletion is the process of destruction of the ozone layer which can cause adverse effects on the living forms by many pollutants releases out from the vehicles, industries etc. Stratospheric ozone depletion, ultraviolet radiation and. Near the ground, ozone is an air pollutant that causes lung damage and asthma attacks. There is a lot of confusion surrounding the role played by ozone in global climate change. It is thickestnear the surface and thins out with height until iteventually merges with space. Effects of stratospheric ozone depletion the environment. The third body m absorbs the excess energy liberated by the above reaction and there by stabilise the o 3 ozone molecule. A polar vortex is a large pocket of very cold air, typically the coldest air in the northern hemisphere, which sits over the polar region during the winter season. Causes of ozone depletion ozone depletion occurs when the natural balance between the production and destruction of stratospheric ozone is tipped in favour of destruction. Ozone depletion over india with so much worry about the rapid ozone depletion taking place in various parts of the earth, indian scientists are closely monitoring the ozone layer over india for possible depletion trends. Polar vortex in the previous posts, we have studied about tropical cyclones and extra tropical cyclones temperate cyclone. Depletion to ozone layer depletion does not affect a region or a country. Ozone depletion has been observed over the past decades, and is most likely.
Effects of ozone depletion ozone depletion is affecting the human health and environment negatively, as it allows the penetration of uv radiations to reach the earth. The ozone depletion resulted in secondary production of an ozone layer near the ground terrestrial ozone layer, which is responsible for adverse effects on plants, humans and environment with. Pinatubo in 1991 which have occurred since we started monitoring ozone with satellites in the late 1970s, could have also contributed to the. It acts as a blanket and keeps the atmosphere cool. Pdf ozone o 3 is a stratospheric layer that plays important role in providing support. Human activities cause ozone depletion and global warming. The troposphere generally extends to a level about 6 miles up, where. Ozone layer depletion is one of the major environmental issues which is getting thinner day by day as a result of increasing pollution. The stratosphere gets its name because it is stratified, or layered. The ozone layer prevents most harmful uv wavelengths of ultraviolet light uv. Automobile exhaust and industrial emissions release a family of nitrogen oxide gases nox and volatile organic compounds voc, byproducts of burning gasoline and coal. Chlorofluorocarbons or the cfc are the main cause of ozone layer depletion. Ozone layer depletion leads to decrease in ozone in the stratosphere and increase in ozone present in the lower atmosphere. Approximately 90 percent of the atmospheres ozone occurs from 1018 km 611 miles to.
The thinning is most pronounced in the polar regions, especially over antarctica. Ozone depletion is largely a result of manmade substances. This depletion makes humans more vulnerable to the uvb rays which are known to cause skin cancer as well as other genetic deformities. Causes, effects and solutions of ozone layer depletion. Environmental effects of ozone depletion montreal protocol. The atmosphere is mostly transparent to the visible except for scatter. Ozone, while a minority constituent in earths atmosphere, is responsible for. Advantages and disadvantages of ozone layer answers. Ozone is formed by photochemical reaction, followed by three body reaction. What are the effects of pollution on the ozone layer. Formation and depletion effect of the montreal protocol on stratospheric cl sunlight incident on earth is very roughly.
The ozone layer is one layer of the stratosphere, the second layer of the earths atmosphere. Most ozone is found in the stratosphere upper part of the atmosphere, more than 10 to 16 kms from the surface of the earth. It was agreed on 16th september 1987, and entered into force on 1st january 1989. How severe is the depletion of the antarctic ozone layer. Ozone layer depletion causes, effects and solutions 7. The ozone layer, in the stratosphere, is where about 90% of the ozone in the earth system is found. The natural distribution of ozone around the earth is. The ozone layer in the stratosphere is thin but powerful. Humans have introduced gases and chemicals into the atmosphere that have rapidly depleted the ozone layer in the last century.
Global warming and ozone layer depletion are two different problems see the sidebar misconceptions about global atmospheric change on page 95. Scribd is the worlds largest social reading and publishing site. One of the greatest and most dangerous effects of pollution on the ozone layer is that it creates holes in the atmosphere, which allow powerful ultraviolet rays from the sun to reach the earths surface. Ozone in the lower atmosphere contributes to global warming and climate change. Nitrogenous compound nitrogenous compounds emitted by human activities in small amount like no, n 2o and no 2 are considered to be greatly responsible for the depletion of ozone layer. The main causes responsible for the depletion of the ozone layer are listed below. Air pollution and ozone depletion flashcards quizlet. Depletion of this layer by ozone depleting substances ods will lead to higher uvb levels, which in turn will cause increased skin cancers and cataracts and potential damage to some marine organisms, plants, and plastics. Ozone can also be found in the troposphere, the lowest layer of the atmosphere. Pdf depletion of the ozone layer and its consequences. The stratosphere increases in warmth with elevation because ozone gases in the upper layers absorb. The montreal protocol is an international treaty designed to protect the ozone layer by phasing out the production of numerous substances that are responsible for ozone depletion.
Ozone layer depletion is one of the major environmental issues which is getting thinner day by day as a. The ozone layer and its depletion linkedin slideshare. Although natural phenomena can cause temporary ozone loss, chlorine and bromine released from manmade compounds such as cfcs are now accepted as the main cause of this. Layers of the atmosphere 45the suns utraviolet rays 68the ozone layer 9 3 4. Questions and answers about the environmental effects of the ozone layer depletion and. The ozone layer is a belt of the naturallyoccuring gas ozone that sits at an altitude of between 15 and 30 kilometers above the earth. The ozone hole and global warming union of concerned scientists. Evidence of ozone depletion in the stratosphere began to appear in the 1980s.
Figure 1 presents only one of the chemical processes responsible for the destruction of ozone in the. In fact whole world is vulnerable to its after affects. Case study on ozone layer free download as powerpoint presentation. Depletion of stratospheric ozone o3, as commonly known as the hole in the ozone layer, is an issue of international concern. Ozone depletion consists of two related events observed since the late 1970s. The stratosphere is the mass of protective gases clinging to our planet. Many varieties of atmospheric pollutants toxic chemicals, synthetic substances, such as ddt, and manmade chemicals enter the atmosphere. By the usual definition, stratospheric ozone depletion is not an integral part of the. The stratospheric ozone layer protects life on earth by absorbing the damaging, highenergy uvc radiation. Newly detected ozonedepleting substances in the atmosphere pdf. But now scientists are concerned that the substances used to replace these ozonedepleting chemicals are.
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