Ozone is a gas found in the upper atmosphere and at ground level of the Earth’s surface. Ozone will mainly be found in two regions of the Earth’s atmosphere closer to our Earth. About 10% of Ozone is found in the region that starts from ground level of the earth known as the troposphere. According to scientific research findings this region of the earth’s atmosphere (troposphere) contains ozone that could be either good or bad depending on how closer it is to the surface of the Earth. The principle of ozone to nearer earth is that ozone is ‘’good up high’’ and ‘’bad nearby’’. Most of the ozone, that is, about 90% is found in the next atmosphere called stratosphere which starts about 10 and 17 kilometres above the Earth’s surface and extending up to about 50 kilometres. Generally Ozone gas is beneficial to human and other life on earth. It is ‘’chemically reactive oxidizing agent that is used as an air purifier, a water steriliser, and a bleaching agent’’. The Ozone in the stratosphere region forms what is known as the Ozone layer.
Chemically ozone gas with a formula (O3) is formed from molecular oxygen (O2) in the stratosphere at an attitude of about 25km by the action of ultraviolet frequency photons .The formula O3 for ozone gas means the ‘’ozone molecules consists of three actions of oxygen arranged in the shape of wide V’’ .Scientific research also indicate that the ‘’name ozone is derived from the Greek word ozein, which means to smell or reek’’.
THE IMPORTANCE OF OZONE LAYER TO THE ENVIRONMENT
This Stratosphere region containing much of the 90% ozone is called the ozone layer. The ozone layer is said to be very important to the environment and life. Here are the importances of the Ozone layer:
In the first place the ozone gas found in the stratosphere is also referred to as ‘’good ozone’’. This ozone layer has a major role of absorbing most of the biologically damaging ultraviolet sunlight known as the UV-B. It does this by allowing only a small amount of ultraviolet rays pass through to the earth’s surface. .The ‘’ozone layer absorbs 97–99% of the Sun's medium-frequency ultraviolet light, which otherwise would potentially damage exposed life forms near the surface’’ of the Earth. Additionally, according to scientists, ‘’the absorption of ultraviolet radiation by ozone gas crates a source of heat which actually forms the stratosphere itself.
Again, the ozone layer plays a key role as temperature structure of the earth’s atmosphere. Therefore, without the filtering action of ozone layer the earth’s surface could be receiving more of the sun’s ultraviolet radiation that has an adverse impact on human health and the surrounding environment. In short the ozone found in the stratosphere (ozone layer) protects everything living on earth (human being, animals, aquatic creatures, plants, etc) from harmful ultraviolet rays coming from the sun. Without the ozone layer it would be very difficult for anything to survive on the surface of the earth. The impact on these living and non-living things would be unbearable without the protection of ozone layer.
In summary, the ‘’ozone layer or ozone shield refers to a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet (UV) radiation’’. This region contains ‘’high concentrations of Ozone (O3) relative to other parts of the atmosphere, although still very small relative to other gases in the stratosphere’’. The ozone layer is said to contain ‘’less than 10 parts per million of ozone, while the average ozone concentration in Earth's atmosphere as a whole is only about 0.3 parts per million’’.
EFFECTS OF DEPLETION OF THE OZONE LAYER ON THE ENVIRONMENT AND LIFE
Depletion of ozone layer is the losing of the Earth’s protective layer available in the stratosphere to such an extent that there is little ozone left to absorb the harmful ultraviolet rays (UV-B). It could also refer to the reduction of the ozone gas in the stratosphere.
Mainly, human activity on earth has been associated to the depletion of the ozone layer of the stratosphere. This human activity responsible for ozone layer depletion is the ‘’ozone depleting compound of combined carbon with chemical elements chlorine, fluorine, bromine and hydrogen collectively called halocarbon’’. According to the chemistry of these compounds, ‘’chlorine and bromine atoms are released from these compounds responsible for the breakdown of stratospheric ozone (ozone layer). The ozone ‘’destruction cycles are catalytic, meaning that the chlorine or bromine atoms enters the cycle, destroy another ozone molecule’’. Therefore, plenty of this gas reaction in the stratosphere depletes the ozone layer leaving it very thin to absorb the harmful Ultraviolet (UV)
The ozone layer depleted will in this case, allow easy penetration of more ultraviolet rays which causes a lot of harm to the environment and life. The effects of ozone layer depletion on the environment and life are great as could be observed and felt in our daily lives. The following are the effects of Ozone layer depletion:
On the environment, Ozone layer depletion has been observed and felt from the global warming throughout the world. According to scientists, global warming has indicated rapid rise in temperatures of the earth’s atmosphere. The temperature increases have been linked to the green house gas emissions by human activities. Global warming has in the first place, affected the natural weather patterns which are very unpredictable in different regions of the world. Storms, cyclones, tomados, floods and many more are the effects of the weather pattern changes. A lot of countries in the Middle East, America, Australia and others are affected by the catastrophic weather changes.
On the other hand, global warming resulting from the intense heat waves penetrating through the depleted ozone layer has affected some infrastructure on the land. For example, in May 2015 India experienced melting of some tarmac roads. The heat waves which reached 122 F(50C) in May melted zebra crossings in Delhi (Rhohit/mani/New Derhi@joset kisdrunk), and dried up land in Gauribidanur village near Bangalore to such an extent of leaving the wet farm lands with cracked surfaces which left farmers shocked.
In Zambia, similarly, the depletion of this natural shield (ozone layer) has chromatically caused dry spells in some parts of the country. At the time of writing this assignment, Eastern, Western and southern provinces were experiencing dry spells which dried up maize farms for commercial and subsistence farmers. In addition, Zambia experienced drying of some important waterfalls such as Victoria Falls affecting the normal supply of electricity to all parts of the country through the national grid.
The excess ultraviolet radiation reaching earth due to the depleted ozone shield has affected the physiological and developmental process of plants. There has been changes in the species composition such as ‘’forests and grasslands where bio-diversity in different ecosystems have been drastically altered”. And this has mainly affected what are called terrestrial plants. The reports of researchers on the effects of global warming have shown that ‘’plants and Animals will find it difficult to escape from or adjust to the effects of global warming”. There has been shifts in the life cycles of many plants and animals, such as flowers blooming earlier and birds hatching earlier in the spring and scientists have also observed that ‘’ plants will also attempt to shift their ranges, seeking new areas as old habitants grow too warm”. It is very clear that harmful effects of excess ultraviolet rays have affected the crop production and forest growth.
On agriculture globally, the global warming resulting from the ozone layer depletion allowing a lot of heat from the sun reaching our earth has caused a lot of harm. Due to intense global warming some parts of the world are experiencing low agricultural productions because of low levels of water supply. In Africa for instance, less rainfall has affected tropical farm lands giving very poor yields of main crops like maize.
Again in some parts of the globe such as the Central valley of California in America farmers depend on water supplied for irrigation from distant mountains where winter snow packs act as water reservoir to be used in summer. These snow packs have been experiencing melting before the peak glowing mouths. As a result agricultural productions do not give the expected yield percentages for the Americans.
Another effect of depletion of ozone layer on the environment has been observed by the significant changes to mountain glaciers and ice sheets on the surfaces of the planet. For instance, ice sheets in Greenland, Antarctic and polar sea ice in Arctic have been gradually melting exposing surfaces of the earth. The report was that ‘’over the 20th century, mountain glaciers have receded and melting is becoming more and more rapid. This melting of glaciers and ice sheets on the earth’s surfaces has accelerated the place of global warming’’. It is scientifically proven that these glaciers and ice reflect sunlight back out to space thereby giving ‘’a cooling effect”. What happens in these places is that land is exposed, absorbing and retaining more heat. As a result more and more of these places are drying up causing water levels in rivers, lakes and oceans rising up and again causing floods. According to reports on this point it is believed that ‘’by the end of the 21st century seal level is projected to rise another 28 to 58cm”.This will complicate life in many islands and coastal regions. Erosion of cliffs, beaches and dunes will increase as the seas invade the mouths of rivers and flooding from runoff will also increase.
On the part of human life, the effects caused by the depletion of the ozone layer have been devastating and uncomfortable. Human health has been greatly affected. The effects of excess ultraviolet rays have caused the following on human beings: * Eye diseases. This is due to the harmful ultraviolet rays which affect the eyes as people walk along in the sunshine. This is very common in tropics of Arica and Asian countries. * Skin cancer. Many light skinned people especially whites develop skin cancer when exposed to intense heat. Ladies in Africa who use skin lightening cosmetics are at risk of developing skin cancer especially when exposed to ultraviolet rays. * Infectious diseases. Some of the infectious diseases common to human beings are as a result exposure to harmful rays coming from direct sunlight. For example, SAS could come as a result of sun light. * Damage on cornea and lens of the eyes. Apart from ultraviolet rays from the sun causing eye diseases, intense rays can damage the parts of the eye such as cornea and lens inside the eye. * Cataracts of the cortical and posterior sub capsular forms. This is common in Africa. Cataracts of the cortical occur due to excessive heat. * Immune system interruptions causing a number of infectious diseases. Due to a lot of harmful ultraviolet radiations the immune system is altered inside the body of a human being. This why a lot of today suffer from diseases such as high blood pressure and Ebola in Africa. * In light skinned human rays cause no melanoma skin cancer. As already alluded to skin cancers will come in different forms resulting from intense sun rays. * Decreases immune responses to the skin cancer, infectious agents and other antigens. What this means is that the immune system which is responsible the protection of the human from diseases will break down when too much ultraviolet rays fall on our bodies. * Sun burns. Sun burns will appear on the surfaces of the skin such as the face because of uncontrolled heat coming from the sun. The sin appears as if the person has been heat by fire.
Due to excessive heat falling on our bodies there will be a lot of incurable diseases in the world. According to scientific predictions, ‘’more people will get sick or die from heat stress, due not only to hotter days but importantly to warmer nights (giving sufferers less relief). More frequent and intense heat waves will further contribute to this trend”. This scientific prediction on the earth show that already people have died from the intense heat waves. In India , on May 27, 2015 Abhisheknsa Saha@Saha abbbi 1990 reported that ‘’Death toll in India’s intense heat wave soars to over 1,100”, and as already alluded to, this caused Zebra crossings in Delhi’s melt on some Indian roads. Another example of the fulfilment of this scientific prediction was in Japan. The report by Philippine News Agency on August 4, 2015 was that ‘’Japan heat wave killed 25, hospitalised nearby 11,700 within 1 week”. Therefore, these excess ultraviolet (UV) radiations penetrating easily through the depleted ozone layer has been and will be worse on human health as long as we continue with activities that produce CFs (chlorofluorocarbons) which are responsible for breaking down ozone gas atoms in space.
Other effects resulting from depletion of the ozone layer are on some world materials such as, plastics, rubber, fabrics and many construction materials which will be degraded by the ultraviolet radiations.
Aquatic ecosystem is another area that has been affected by the depletion of the ozone layer. The effect has been intense on productivity of aquatic systems where the distribution of phytoplankton has been disturbed. Phytoplankton which is the foundation of food for aquatic life has been damaged early before the development of species such as fish, shrimp, crab, amphibians and other animals. Due to this there has been drastic decrease in the reproductive capacities of many of these aquatic species.
Lastly, the economic impact resulting from the effects of ozone layer depletion has been very significant. Countries have been struggling to mitigate the impact but this has always been very costly. However, the struggle to find a lasting solution to the effects of climate change (global warming) is on-going. Recently, a summit in France (COP21) on climate change resulted in leaders reaching a deal to ‘’Save the World” from completely collapsing. ‘’The pact is the first to commit all countries to cut carbon emissions. The agreement is partly legally binding and partly voluntary. President of the UN climate conference and French Foreign Minister Laurent Fabius Said; ‘now i invite the cop to adopt the decision entitled ‘’Paris Agreement’’ out lined in the document’.
It is the wish of many on globe to see that agreement reached in Paris-France will yield positive results in slowing down the ozone layer depletion. Scientists again predicted that restoration of the ozone layer to its normal thickness might another 50 years.

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