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The Earth has a Layer of Ozone at the Edge of the Stratosphere
The ozone layer is in a layer of the atmosphere called the stratosphere.
It contains most of atmospheres molecules, 03.
Ozone is formed when UV radiation from the Sun hits the oxygen molecules.
If the right amount of UV radiation is absorbed by an oxygen molecule, the oxygen molecule
splits into two separate atoms or free radicals.
The free radicals then combine with other oxygen molecules to form ozone molecules, 03.
O2 + hv O · + O · O2 + O · O3
The Ozone layer is constantly being replaced
UV radiation can also reverse the formation of ozone
So, the ozone layer is continuously being destroyed and replaced as UV radiation hits the
An equilibrium is set up, so the concentration stays fairly constant.
O3 + hv O2 + O ·
The Ozone layer protects us against UV Radiation
The ozone layer is incredibly important for us it protects us from most of the harmful
effects of the Sun's ultraviolet radiation.
The ozone layer removes all of the high energy UVC radiation and about 90% of the UVB
These types of UV radiation are harmful to humans and most other life on earth.
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UVB can damage the DNA in cells and cause skin cancer, and is the main cause of sunburn.
UVA can also lead to skin cancer.
Both types causes the skin to age faster.
But, the UV radiation isn't all bad in fact it's essential for us humans. We need it to
produce vitamin D.
Also, when the skin's exposed to UV, it tans. This helps protect deeper tissues from the
effects of radiation.…read more