Climate is constantly changing in this diverse world. Ozone layer depletion is one of the causes of climate change. The ozone layer in the upper atmosphere protects the planet from harmful ultraviolet rays from the sun.
Ozone layer A layer of the Earth’s atmosphere that contains relatively high concentrations of ozone gas. The presence of ozone gas is observed in the stratosphere, which is 20 to 30 km above the earth’s surface. The stratosphere covers the region like a hollow sphere. Ozone is a special type of gas with a light blue odor. Composed of three oxygen atoms (E3). It is much less stable and more reactive than oxygen, causing it to form and break easily by interacting with other compounds. The boiling point of liquid weight is 1124 kcal – the melting point of solid ozone is 249.7 kcal.
French physicists Charles Fabry and Henri Buisson discovered the ozone layer in 1913. Later British meteorologist GMB Dobson did extensive research on the ozone layer. Between 1928 and 1958 he built a network of ozone monitoring stations. Ozone gas is formed when oxygen molecules in the upper atmosphere are broken down by ultraviolet radiation. It combines with oxygen molecules (E2) to form three oxygen atoms known as ozone gas (E3).
The main function of the ozone layer is to protect the living world from the sun’s harmful ultraviolet rays. The gentle effects of the sun’s UV rays are felt only when we step out into the harsh sun. We usually use sunscreen to protect ourselves from the sun. But luckily the earth protects us from the harmful effects of UV rays through its own sunscreen (ozone layer).
An essential ingredient for creating ozone gas is oxygen gas, which absorbs ultraviolet light and prevents that light from reaching the Earth’s surface. Oxygen gas and another form of oxygen, the allotrope, exist in abundance in the ozone layer.
Most ecosystems depend on the ozone layer for protection from harmful radiation. Ultraviolet rays have shorter wavelengths than visible light, so they are not visible to humans. But some other insects, including bees, can see the rays.
The harsh rays of the sun have the ability to burn our skin as well as cause skin cancer, cataracts and damage the body’s immune system.
The natural covering of the atmosphere’s stratosphere to absorb and repel ultraviolet rays is being eroded day by day. Scientist Farman identified the depletion of the ozone layer as the ozone hole.
In 1982, a group of British scientists surveying the Antarctic region noticed that the ozone content over a large area of the upper atmosphere had become extremely depleted. Over the next few years, they continued to experiment and found that this ozone depletion was becoming more and more widespread, creating a hole known as the Earth’s ozone hole. If the amount of ozone destruction is greater than the creation of ozone gas, ozone holes are formed. In 2000, an ozone hole was observed in the southern part of Comoros and Latin America with an area of 285 million square kilometers.
Ozone layer depletion is one of the environmental degradation of the world in the present century. Two reasons can be observed for ozone layer depletion; Man-made causes and natural causes. The ozone layer is depleted due to several natural causes such as: destruction of ozone gas in the presence of ultraviolet rays due to light reactions, destruction of ozone gas by nitrogen oxides, hydrochloric acid, chlorine. Ozone is also destroyed naturally by volcanic eruptions.
Studies have shown that since 1915, human activities have been driving the Earth towards extinction. One of them is human-caused ozone depletion. In the modern world, the invention of the atomic bomb has released so much chemical energy into the atmosphere that combines the inert nitrogen in the atmosphere with oxygen to produce nitrogen oxides, which are responsible for the destruction of the ozone layer.
Water vapor and nitrogen oxides emitted by supersonic aircraft react with N3 gas to destroy ozone. Chlorofluorocarbons (CFCs) and chlorofluoromethanes (CFCs) are the main ozone-depleting gases. A single particle of ozone can destroy more than a hundred thousand ozone particles. Such gas, used in refrigerators, air conditioners, spray cans, airplane propellers, foam, plastics, etc., gradually reaches the stratosphere.
Here, under the influence of infrared rays, first chlorine (EO) turns into atoms and that chlorine (EO) reacts with ozone particles and destroys ozone. Excessive use of chemical pesticides in agriculture disrupts the balance in the atmosphere. Nitrogen fertilizers in agriculture produce nitrous oxide, which is an ozone depleting substance. Decomposing plant parts and methane gas from agricultural waste, animal manure and oil fields contribute to the ozone hole. Methane gas breaks down ozone molecules in the atmosphere.
As a result of ozone depletion, the world’s biodiversity is under serious threat. People are suffering from more complex diseases including skin cancer, breast cancer, leukemia, cataracts due to the effect of ultraviolet rays. Immunity, reproductive capacity is decreasing due to the effect of toth. Ozone layer depletion is also a major threat to plants. Photosynthesis and seed germination will be disrupted. White spots can be noticed by changing the color of the leaves. 20-25% leaf chlorophyll content is reduced due to Toth-E.
A lack of sufficient chlorophyll prevents plants from making food. Due to ozone depletion in the atmosphere, the surface temperature is increasing day by day. In the next 40 years, due to ozone depletion, 5 to 20 percent of the sun rays will fall on the earth’s surface, resulting in global warming. As a result, the ice in the polar regions will melt and the sea level will start to rise. If the amount of ozone in the stratosphere decreases, the amount of hydrogen peroxide in the troposphere will increase, resulting in the formation of acid rain. If ozone depletion is not controlled, ecosystem productivity and sustainability will be out of balance. The ozone layer is completely controlling the adverse reactions of the environment and climate change.
Carbon released from various fuels is one of the causes of ozone depletion. America, China, Russia, India, Germany and the United Kingdom emit 60% of the world’s carbon. To protect the ozone layer, these countries need to reduce carbon emissions and provide alternative fuels. Reduce the use of fossil fuels and increase the use of environmentally friendly technologies such as solar energy, wind energy, hydropower and renewable energy.
The use of technology is increasing everywhere in the world today, the effects of climate change are visible. Therefore, in order to leave a beautiful habitable green earth for future generations, industrialized countries should play the most important role in protecting the ozone layer.
An important way to protect the ozone layer is to stop the use of harmful gases such as CFCs or chlorofluorocarbons, methyl bromide and nitrous oxide. Reducing the use of private vehicles that add carbon monoxide and nitrogen oxides. The use of refrigerators, air conditioners, spray cans should be reduced or alternative arrangements should be made. Because CFC gas can escape into the atmosphere. Several greenhouse gases are produced during the manufacture of chemical fertilizers. So we should reduce the use of fertilizers in agriculture and increase the use of organic matter. Indiscriminate deforestation must be prevented.
According to the World Meteorological Organization, the amount of ozone layer rupture was 27 million square kilometers in 2008, 25 million square kilometers in 2006, and 24 million square kilometers in 2009. Although it is possible to reduce this amount in 2009, it is not out of danger.
In 1985, governments around the world adopted the Vienna Convention for the Conservation of the Ozone Layer. Two years later, on September 16, 1987, the “Montreal Protocol” was adopted in Montreal, Canada to ban or limit the use of substances responsible for ozone depletion. In commemoration of the day, the United Nations General Assembly declared 16 September as “World Day for the Protection of the Ozone Layer”. The essence of the agreement adopted in the Montreal Protocol is that by 1995, all developed countries must stop the production of CFCs and Halon gas, and stop the production of carbon tetrachloride (CTC) and trichloroethane (TCC). The use of hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HCFCs) as substitutes for chlorofluorocarbons must be phased out by 2040.
In 1989, the British government and the Tongan Environment Program organized a conference in London known as the London Conference. The conference decided to reduce the production and use of ozone-depleting chemicals and to develop alternative chemicals that do not destroy the ozone layer. Year 3 production should be reduced by 20 percent. Proper implementation of Montreal Protocol and other international laws is essential to leave a habitable earth for future generations.
Ozone layer is protecting our earth so it is our responsibility to protect it too. Earth is the only planet in the universe where the creator has created a beautiful environment for human beings to live. The hanging universe is always moving. There is no negligence among cosmic objects in fulfilling their own responsibility. I only see carelessness in people. Which does not suit the best creatures for humans. Carelessness must be avoided if duty is to be carried out with care. Let us be careful. Reduce vehicle emissions; Use all appliances including refrigerators, air coolers in a hygienic manner. Keep CFC gas generation within tolerance limits. Maintain an overall pollution free environment. All live in good health.
Al Jarsam Hossain Rafid
Geography and Environmental Science
Begum Rokeya University, Rangpur.