International Ozone Day

why ozone layer is important for human and planet earth

What is an Ozone Layer?

The ozone layer works as a protective screen, absorbing UV rays from the sun, commonly represented as O3 and comprises three oxygen atoms. This layer is located between 15 to 30 kilometres above the Earth’s surface in the stratosphere. It produces natural UV light from the sun, reacting with molecular oxygen (O2). However, in a nutshell, we could say that ozone serves as a layer that shields harmful rays and pollutants.

Causes and effects of Ozone layer depletion

Several regularly used compounds have been discovered to be particularly harmful to the ozone layer. Halocarbons are compounds with one or more carbon atoms bonded to halogen atoms (fluorine, chlorine, bromine or iodine). Bromine-containing halocarbons typically have a substantially higher ozone-depleting potential (ODP) than chlorine-containing halocarbons. The artificial substances that have provided the majority of the chlorine and bromine for ozone depletion are methyl bromide, methyl chloroform, carbon tetrachloride, and the halons, chlorofluorocarbons (CFCs), and hydrochlorofluorocarbons families of chemicals (HCFCs).

Depletion of stratospheric ozone occurs over both hemispheres of the Earth. However, this phenomenon is less severe in the northern hemisphere (Arctic) than in the southern hemisphere (Antarctica). This is because meteorological variability is more significant over the Arctic than in the Antarctic year-to-year. Furthermore, temperatures in the stratosphere do not remain low for a long time in the Arctic, as in the case in the Antarctic.

The concentration levels of 220 Dobson Units (DU) or less (in blue in the figure) show severe ozone depletion and develop “ozone hole”. Basically, It is an area or a region of significant ozone layer thinning in high latitudes, primarily in winter, caused by the chemical action of CFCs and other atmospheric contaminants. This is only apparent in the southern hemisphere. Here, the most significant historical extent of the ozone hole – 28.4 million km2– occurred in September 2000. This area is equivalent to almost seven times the territory of the European Union (EU).

Maximum ozone hole extent over the southern hemisphere (1979-2021)

Preservation of the Ozone Layer

Hazardous chemicals emitted through aerosol sprays, refrigerants, solvents, propellants, foam-blowing agents, and other sources cause ozone layer depletion. UV radiations break down chlorofluorocarbon molecules in the stratosphere, releasing chlorine atoms. The influence of radiative forcing on the climate increases as greenhouse gas concentrations rise. The breakdown of stratospheric ozone by substances such as chlorine radicals increases UV radiation at the terrestrial level. These distinct occurrences are part of a more prominent family of global environmental changes. Scientists claim that in the early 1970s, stratospheric ozone levels in the polar regions began to decline. But the ozone’s condition has improved, according to a 2018 “Ozone Depletion Factor” measurement. Also, some of the climate change is now slowed down by continuous efforts.

World Ozone Day

Ozone Day aims to achieve the objectives of the Montreal Protocol and its amendments and promote public awareness about the importance of protecting the Ozone Layer from depletion. The ozone layer protects us from the sun’s ultraviolet radiation (UV rays). The Montreal Protocol forbids the use of substances that weaken the ozone layer with the long-term goal of eliminating them in light of new scientific and technological knowledge. Its structure is based on many categories of ozone-depleting chemicals. Nearly 100 substances across various types must be under control according to the Protocol. The Treaty lays out a timeline for phasing out the production and consumption of each class or annexe of chemicals to eliminate them.

Montreal Protocol (2022)

When the Montreal Protocol was signed in 1987, all 197 members of the United Nations voted in favour of it. The Canadian city of Montreal typically plans several special events, lectures, and seminars on September 16 every year. The United Nations General Assembly (UNGA) established International Day for preserving the Ozone Layer in 1994. The day’s primary goal is to raise awareness about the Ozone Layer’s depletion and to look for ways to protect it. On September 16th, people from all over the world will gather in Montreal to attend the speeches and seminars. Educators frequently set aside this day to teach their pupils about the Ozone layer, and many schools organise special events and activities to increase awareness.

The Montreal Protocol@35: The theme of the 2022 International Day for the Preservation of the Ozone Layer, which will be held on September 16th, is global cooperation to protect life on Earth. The theme recognises the Montreal Protocol’s broader impact on global warming and the need to act in harmony, form partnerships, and develop international collaboration to solve climate challenges and protect life on Earth for future generations.

Why is Ozone Day Important?

The ozone layer preserves life on Earth by absorbing harmful UV radiation, which is essential for life to exist on this planet. The ozone layer protects us from the sun’s ultraviolet radiation (UV rays). UV radiation from the sun causes cataracts, blindness, a weakened immune system, skin ageing, and other health issues. Direct UV radiation exposure in animals and humans promotes skin and eye cancer. UV-B rays also cause crop damage. UV-B exposure has a significant influence on plankton and zooplankton and a decrease in plant productivity which has an impact on soil erosion and the carbon cycle. Reduced plant growth, smaller leaf size, decreased blooming and photosynthesis, and lower crop quality.

How can we prevent ozone layer depletion

Here are some steps which each of us can put forward to protect the ozone layer from depletion :-

  • Consume ozone-depleting gases as little as possible.
  • Avoid burning plastics and rubber materials, which emit toxic fumes into the environment.
  • Reduce the use of smoke-emitting automobiles.
  • Try to replace hazardous cleaning products, cosmetics, hair spray, air fresheners, and other household products with non-toxic alternatives.
  • Encourage gardening and plantation to lower the risk of harmful pollutants in the atmosphere.
  • Maintain air conditioners as their malfunctioning generates CFC production.
  • Raise awareness on World Ozone Day about the significance of keeping our environment safe and healthy to protect the ozone layer.