The ozone layer is a fragile layer of gas in the Earth's stratosphere that protects us from the sun's harmful ultraviolet (UV) radiation. It is essential for life on Earth as we know it.


What is the ozone layer?

The ozone layer is a region of the stratosphere, roughly 15 to 35 kilometers above the Earth's surface, that contains a relatively high concentration of ozone (O3) molecules. Ozone is a gas composed of three oxygen atoms, while the more common form of oxygen in the atmosphere is oxygen gas (O2), which consists of two oxygen atoms.


How does the ozone layer protect us?

The ozone layer absorbs most of the sun's UV radiation, which is harmful to living things. UV radiation can damage DNA, leading to skin cancer, cataracts, and immune system suppression. It can also harm plants and ecosystems.


Threats to the ozone layer

The ozone layer is under threat from several human activities, including:


Chlorofluorocarbons (CFCs):

 These are synthetic chemicals that were once widely used in refrigerants, aerosol cans, and other products. CFCs break down in the stratosphere, releasing chlorine atoms that destroy ozone molecules.

Halons: 

These are fire-fighting chemicals that also contain chlorine and can damage the ozone layer.

Nitrous oxide:

 This gas is emitted from agricultural activities and the burning of fossil fuels. It can also contribute to ozone depletion.


The consequences of ozone depletion:

The depletion of the ozone layer has led to an increase in UV radiation reaching the Earth's surface. This has resulted in:


Increased rates of skin cancer:

Skin cancer is the most common cancer in the United States, and the rate of new cases has been increasing in recent decades.

More cataracts:

 Cataracts are a clouding of the lens of the eye that can lead to blindness. UV radiation is a major risk factor for cataracts.

Weakened immune systems:

UV radiation can suppress the immune system, making people more susceptible to infections.

Damage to plants and ecosystems:

 UV radiation can harm plants, reducing crop yields and disrupting ecosystems.


Protecting the ozone layer:

The international community has taken action to protect the ozone layer by phasing out the production and use of ozone-depleting substances. The Montreal Protocol, an international treaty signed in 1987, has been highly successful in reducing the levels of CFCs and other harmful chemicals in the atmosphere. As a result, the ozone layer is slowly beginning to recover.


What can you do?

There are a number of things you can do to help protect the ozone layer:

•Avoid using products that contain CFCs.

•Limit your exposure to UV radiation by wearing sunscreen, protective clothing, and sunglasses.

•Support policies that protect the ozone layer.

•By taking action to protect the ozone layer, we can help ensure a healthy planet for future generations.


Additional resources:

* The World Meteorological Organization (WMO) Ozone Website: [https://public.wmo.int/en/environment/ozone/ozone-assessment](https://public.wmo.int/en/environment/ozone/ozone-assessment)

* The United States Environmental Protection Agency (EPA) Ozone Layer Protection: [https://www.epa.gov/ozone-layer-protection]