Montreal Protocol – the world’s most successful treaty

“Alone we can do so little; together we can do so much. – Helen Keller”

In 1987, countries around the world came together to sign it. Their mission? To save the ozone layer and signed the world’s most successful treaty – the Montreal Protocol.

 Without the treaty, the hole in the Antarctica ozone would have been 40% larger in 2013.

Phasing out 99% of ozone-depleting chemicals in refrigerators, air conditioners and other products.

What is the Ozone layer and why is it required?

The ozone layer or ozone shield is a region of Earth’s stratosphere (layer in the earth’s atmosphere) that absorbs most of the Sun’s ultraviolet radiation. It contains a high concentration of ozone (O3) in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere

This ultraviolet radiation can lead to many harmful health conditions such as skin cancer, cataracts, and impaired immune systems. It can also decrease plant growth and disrupt food chains. The ozone layer prevents these deadly radiations from reaching the earth’s surface.

It is estimated that up to 2 million cases of skin cancer worldwide may be prevented each year by 2030.

Ozone layer - usefulness
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What led to the hole in the ozone layer?

The ozone hole was caused by the depletion of the layer due to chemical species such as Nitric oxide (NO), nitrous oxide (N2O), Hydroxyl (OH), atomic chlorine (Cl), and atomic bromine (Br). Also, chemicals called chlorofluorocarbons (CFCs) and bromofluorocarbons – widely used in aerosol cans, fire retardants and fridges.

When ultraviolet radiations strike these species, they produce free radicals and each free radical can lead to breaking down of over 100,000 ozone molecules.

Ozone layer depletion
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How the Montreal Protocol came into force?

Throughout the 1970s, scientists began to observe two separate but related phenomena: the total amount of ozone in the stratosphere — the region 10 to 50 kilometers above the earth’s surface — was declining steadily at about 4% every ten years. And in spring there was a much larger decrease in stratospheric ozone over the polar regions.

The risk imposed on human health due to depletion of the ozone layer was so huge that even before the significant ozone depletion was detected in 1985 the Vienna Convention for the protection of the ozone layer was agreed on. The convention came into force in 1988 and was signed over the following decades by 197 nations, making it one of the most successful treaties of all time.

Then, next year in 1989, the Montreal Protocol (which falls under the Vienna Convention) also came into force – imposing a ban on production and consumption of numerous substances that are responsible for ozone depletion. 

How much successful the treaty is?

Montreal Protocol Success
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Last year, the Antarctic ozone hole hit its smallest annual peak on record since 1982. 

According to NASA and the NOAA, the annual ozone hole – which consists of an area of heavily depleted ozone high in the stratosphere above Antarctica, between 7 and 25 miles (11 and 40 kilometers) above the surface – reached its peak extent of 6.3 million square miles on September 8 and then shrank to less than 3.9 million square miles during the rest of September and October 2019. 

The latest Scientific Assessment of Ozone depletion in 2018, confirms that parts of the ozone layer have recovered at a rate of 1-3% per decade since 2000.

More than 135 billion tons of carbon dioxide – equivalent emissions were prevented from reaching the atmosphere between 1990 and 2010.

Scientists predict that the ozone hole will shrink to its 1980 size by about 2070 as CFCs (chlorofluorocarbons) still in the upper atmosphere gradually decline.

My Opinion:

This treaty proves that together we all can fight climate change also. It is just that we have to realize like the ozone depletion that how harmful increasing carbon dioxide concentrations would be. I am very hopeful that we will be able to win the war against climate change because together we can but we will have to do something immediately, as the clock is ticking very fast.

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Yash loves to read and write on issues such as climate change, renewable energy, SDGs, and other related issues. He wants to make people aware of climate change and encourage them to follow a sustainable lifestyle.

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