The Earth’s atmosphere is made of 4 layers – the troposphere, the stratosphere, the mesosphere, and the thermosphere. The ozone layer is found in the lower portion of the Earth’s stratosphere. It is named so because it has the highest concentration of ozone (O3) in the atmosphere. It carries out a very important function of absorbing most of the harmful ultraviolet radiation from the Sun.
What causes this ozone layer to deplete?
Ozone-depleting substances (ODSs) like chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and hydrochlorofluorocarbons (HCFCs) are the prime culprits. They release chlorine and bromine after coming in contact with the UV rays in the stratosphere. These chlorine and bromine atoms destroy ozone molecules. The rate at which ODSs destroy ozone is very high compared to the rate at which it replenishes.
Why does it need saving? What are the effects of ozone layer depletion?
The UVB rays are a part of the UV rays. They are linked with several adverse effects. Exposure to UVB rays harms the DNA in skin cells. This can lead to genetic mutations that may even cause skin cancer. UVB rays can also lead to premature aging. These rays are also linked with cataracts and eyelid cancer. They also cause damage to some crops and marine life.
Ozone depletion was also affecting the jet stream in the southern hemisphere. This jet stream was moving towards the south pole in the last decades of the 20th century. This took the rain-bearing storms south and further away from Australia. This caused dry winters there. It has also affected ocean currents and salinity.
But what exactly has led to the healing of the ozone layer? Two popular candidates have emerged – the Montreal Protocol and COVID-19.
What is COVID-19?
COVID-19 stands for “coronavirus disease 2019”. The novel coronavirus causes this disease. This virus was first identified in Wuhan, China. The novel coronavirus is linked to the same family of viruses as Severe Acute Respiratory Syndrome (SARS).
What is the Montreal Protocol?
The Montreal Protocol is an international treaty in effect since 1987. 197 countries had signed this treaty. The purpose of this treaty is to inhibit the production of ODSs.
But what has led to the healing of the ozone layer?
Thousands have succumbed to COVID-19. Since the coronavirus can spread from physical contact, sneezing, and coughing, social distancing and nationwide lockdown measures have been implemented. approximately one-fifth of the world’s population is under lockdown. Businesses and economies have been dealt a severe blow as all employees have been forced to work remotely. Since most of the masses have been at home for weeks, there has been a sizeable drop in private transport. Manufacturing is another major source of greenhouse gas emissions. Even this sector has taken a halt. As a result, Greenhouse gas emissions have plunged, and air pollution has reduced significantly.
The Montreal Protocol?
For almost 33 years, all the 197 participating nations have complied with the Montreal Protocol. Since the treaty came into effect, atmospheric concentrations of CFCs have reduced. The U. S. Environmental Protection Agency estimated in a 2015 report that the treaty will prevent over 1.5 million skin cancer deaths, and 45 million cataracts in the US alone.
As a result of the Montreal Protocol, the ozone hole in Antarctica has been on the road to regaining its former glory. In 2014 It was estimated that by the 2060s, the ozone layer will be back to how it was in 1980. Without a doubt, the Montreal Protocol is the most successful international agreement ever.
It was reported in 2016 that not only had the ozone layer stopped depleting, but there were signs of the ozone layer healing. Then the UN published a report in November 2018 showing the extent to which the ozone layer had healed. A year later, the UN claimed in a similar report that the healing could be complete “in our lifetime”.
So, 30 years of judiciously following the Montreal Protocol had finally started bearing fruit. Thus, ozone layer healing had started way before the COVID-19 outbreak in December 2019. But COVID-19 also has had a significantly positive effect since December 2019. So, we conclude that the Montreal Protocol has contributed most to the healing of the ozone layer. COVID-19 has been around for a very short time and its contribution can be thought of only as a helping hand.