The Montreal Protocol and the ozone hole...

Does the success of the Montreal Protocol suggest we should expect the same result with limiting GHGs?

What is the ozone layer and why is it important?

The ozone layer is a layer of gas in the Earth's atmosphere that contains a high concentration of ozone (O3) molecules. It is located in the stratosphere, at an altitude of about ~20 to 30 kilometers above the Earth's surface.

The ozone layer plays a crucial role in protecting the Earth from harmful ultraviolet (UV) radiation from the sun. UV radiation is known to cause skin cancer, cataracts, and other health problems in humans, and can also harm plants and animals.

The ozone molecules in the ozone layer absorb most of the UV radiation from the sun, preventing it from reaching the Earth's surface. This shielding effect is particularly important in the tropics, where the sun is strongest and where many people live.

However, in the 1970s and 1980s, it was discovered that certain man-made chemicals, such as chlorofluorocarbons (CFCs), were damaging the ozone layer by breaking down ozone molecules.

Source: https://discoveringantarctica.org.uk/oceans-atmosphere-landscape/atmosphere-weather-and-climate/the-ozone-hole/

How is ozone destroyed?

Chlorofluorocarbons (CFCs) and other ozone-depleting substances (ODS) destroy ozone molecules in the atmosphere through a series of chemical reactions.

When CFCs are released into the atmosphere, they eventually rise to the stratosphere where they are broken down by ultraviolet (UV) radiation from the sun. This process releases chlorine atoms, which can then react with ozone molecules (O3).

The chemical reaction between the chlorine atoms and ozone molecules results in the formation of chlorine monoxide (ClO) and molecular oxygen (O2). The chlorine monoxide can then react with another ozone molecule, leading to the destruction of the ozone molecule and the formation of more molecular oxygen and chlorine atoms. This process can continue, with one chlorine atom potentially destroying thousands of ozone molecules.

The destruction of ozone molecules by CFCs and other ODS results in a thinning of the ozone layer, particularly over the polar regions, where the conditions are most favorable for the formation of the ozone hole which led to the Montreal Protocol.

Source: https://www.brainkart.com/article/Ozone-and-Ozone-Depletion_33813/

What was the Montreal Protocol?