What is the ozone layer?

Ozone-is a substance found in nature, it is the allotrope of oxygen. It exists in the entirety of the atmosphere, but mainly in the ozone layer.

Ozone is formed in the middle stratosphere from oxygen by ultraviolet radiation. It acts as a filter and prevents most of the harmful UV radiation from reaching the Earth’s surface. In industry, ozone is produced by the action of an electric charge on oxygen. It’s used as an OXIDIZER in bleaching, air conditioning and water purification.

The ozone layer is basically a sort of shield for earth. It protects the planet and the living beings on it from copious amounts of UV light radiation. The ozone layer is necessary in for life on Earth. Prolonged exposure to UV radiation can cause skin cancer, retinal burns, and reduce immunity in people. For animals and plants, UV rays are also very harmful.

If the ozone layer had not once formed, life on Earth would have a completely different appearance and, quite likely, would exist only in seas and oceans, hiding under water from dangerous UV radiation.

The ozone layer is considered the thinnest and lightest layer in the atmosphere. The reason is, it’s located at an altitude of 15 to 50 km above the Earth's surface. In different latitudes of Earth, the ozone layer is at different heights, and also has different thickness. But in general, the concentration of ozone in the atmosphere is negligible, if you collect all the ozone in a uniform layer and cover the entire planet, then its thickness will be one-tenth of a millimeter.

It is not known when this layer was formed, but it is widely known that over the past 40 years, the concentration of ozone in the atmosphere has greatly decreased. In some regions, the level of ozone has decreased so much that it has led to the emergence of so-called ozone holes in the atmosphere. The largest hole is over Antarctica, its area is almost twice that of the continent itself.

What is it exactly that has led to the destruction of the ozone layer?

Human activity greatly affects the depletion of the ozone layer and the appearance of holes in it. For example, they are formed when launching rockets. Aircraft flying at a height of 12-16 also contribute to the destruction of the layer. Including the greenhouse effect, mass cattle breeding, industrial emissions of harmful substances, etc.

If we talk about substances that contribute to the destruction of the ozone layer, then freons are the most "effective" of them. Freons are gases that do not enter into any chemical reactions at the surface of the planet. For a long time they were used in aerosols, nebulizers and have now gained popularity in industrial production.

What are people doing to fix the ozone layer?

The most popular example of people trying to fix the ozone layer is the “Montreal Protocol”.

In 1987, the nations of the world came together to save the ozone layer and consequently the planet by banning chemicals known as chlorofluorocarbons (CFCs). Now, three decades later, a NASA satellite and numerous studies have confirmed those measures were successful.

Using a satellite, in the new study published in the journal of Geophysical Research Letters, scientists were able to look at how ozone levels have changed, compared to chemicals in the atmosphere year to year. While we’ve seen the ozone loss decreasing before the CFC ban was introduced, this study is the first to show it is the direct result of banning CFCs.

"All of this is evidence that the Montreal Protocol is working," the team wrote in their paper.

CFCs can take 50 to 100 years to disappear completely, so the progress is quite slow. It might not be until 2060, or even 2080, that the ozone hole has gone completely.

But the Montreal Protocol is a clear example of how the world can come together to solve environmental issues.