Earth without ozone layer, what will affect us, we can easily understand from an example if we roam a couple of weeks in half sleeves direct under sunlight, the effect will be a sun tan which can be easily visible in bright skin people. Now let’s understand about Earth’s ozone layer, its significance, harm causing agents to it, effects of holes in the ozone layer and solutions.
World Ozone Day
World Ozone Day is officially known as International day for the preservation of the Ozone layer, also known as Ozone day. The Ozone layer was discovered in 1914 by French physicist Fabry and Henry Buisson during their study; they had found out about the existence of the Ozone layer. In the decade of 1970-80, scientists found that the hole in the ozone layer was getting increased by ozone depletion gasses(ODS) used in aerosols and cooling used in refrigerators and air conditioning.
In 1987, as a response to this situation, the UN General Assembly adopted the Vienna convention for the protection of Ozone layer, nations also signed to work for increasing depletion of ozone layer. In 1994 the UN General Assembly proclaimed 16 Sep as the international day for the preservation of the Ozone layer.
Ozone layer
Ozone
Ozone is created when highly energetic sun photons form a chemical connection with oxygen molecules (O2). The term “photodissociation” generally refers to this relationship. This process results in the formation of a single oxygen molecule, which is then combined with an oxygen molecule to generate ozone.
Location of Ozone layer
The area of the upper atmosphere with the highest concentration of ozone is located between 15 and 35 kilometers above the surface of the earth; this layer is called the Ozone layer. The stratosphere of the entire atmosphere is where the majority of the ozone layer is found.
Formation of Ozone layer
If we look back in time to when the Ozone layer first formed, it is estimated that between two and six billion years ago, early aquatic organisms known as blue-green algae started using solar energy to convert water and carbon dioxide molecules into oxygen, a process known as photosynthesis. As a result of this process, oxygen starts to build up in the earth’s atmosphere. UV light is absorbed by an abundance of oxygen molecules, which then divide into individual oxygen molecules. These single oxygen atoms (o) begin interacting with oxygen molecules (o2) to generate ozone (o3), which is extremely effective at absorbing UV and solar energy. serves as a shield for soil as well.
Depletion of ozone layer
Depletion of ozone layer by some free radical catalysts are as follows
- Nitric oxide (NO)
- Nitrous oxide (N2O)
- Hydroxyl(OH)
- Atomic Chlorine(Cl)
- Atomic Bromine (Br)
Even these are natural sources of all species, but the amount of chlorine and Bromine increased in last centuries due to large quantities of emission of Chlorofluorocarbon(CFC) and Bromoflurocarbon.
How these are dangerous
- Chlorofluorocarbons and Bromoflurocarbon are highly capable of surviving the rise to the stratosphere.
- From Chlorofluorocarbon and Bromoflurocarbon, Chlorine and Bromine radicals can be easily released by the action of ultraviolet rays of the Sun.
- Each radical of chlorine and Bromine is capable of initiating and catalyzing the chain of reaction.
- A single Chlorine molecule is able to break over 1,00,000 Ozone molecules.
- In 2009, it was found that Nitrous oxide (NO) was the largest ozone depletion substance(ODC) emitted through human activities.
Human activities causing Ozone depletion
Common activities
- Emission of Chlorofluorocarbon from electrical devices like refrigerator, air conditioner, foam blower, aerosol propellant, cleaning of metals and electrical companies.
- Excess use of nitrogenous fertilizer in agriculture.
- Nuclear testing
Other activities
- Releasing methyl Chlorine.
- Releasing halons and methyl bromide
- Increasing other gasses in the stratosphere.
Ozone holes affect on earth
More holes will allow the Sun’s Ultraviolet rays and other harmful radiation to enter the Earth. This will result in a serious effect on earth on animal species and plant species also it will interfere in microorganisms and air quality management.
Effects on human
- UV rays will cause skin cancer, eye cataract and genetic immune system damage.
- Permanent or temporary blindness
- Impaired immune system
- Increased tropospheric Ozone, which is health risk to human
Effects on plants
- Growth: sun’s radiation can reduce plant growth including height and leaf size.
- Photosynthesis: Ozone Depletion will affect photosynthesis resulting in less growth with flowering.
- Reproduction: As photosynthesis is disturbed by Sun’s ultraviolet rays, reproduction of plants will severely affect.
- Survival: As the energy cycle of plants will decrease or stop, eventually survival will also reduce.
Solution
A common problem for depletion of Ozone layer is refrigerator and air conditioning, which is so popular in the world for maintaining a cold temperature leading to a luxury lifestyle. The total abolition of these devices is quite hard but not impossible to apply. World’s economic leaders must be aware of these problems. Alternative devices like refrigerators and air conditioning need to be created, which shouldn’t affect nature. Reducing use ODS, minimizing use of vehicles, need to use eco friendly cleaning products, prohibition of Nitrous oxide will definitely help in recovery of Ozone layer for the sake of the whole world.
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